We had a great 2022 national meeting with great people and great gardens! Don't miss next year's meeting. April 26-29, 2023.

American Forests has just published the 2020 Champion Trees National Register. This is a fun and informative list, and can be sorted by type of tree or location (find the ones in your state) and then sorted by various criteria, such as trunk circumference, height and crown spread. Of course, not all are conifers, but they have a good representation on the list. AF is one of the premier woody plant conservation organizations.

I started by searching for all of the trees in the register from California. Not surprisingly, Sequoia and Sequoiadendron lead the list. But in addition, I found firs, pines, spruces and more. I have bookmarked the page! Now when I plan a trip to visit gardens or nurseries, I will check to see what Champion Tree(s) might be in the vicinity. What Champions are in your neck of the woods?

The author has primarily worked on indie productions, often working with a low budget and local talent, creating scenes that rival professional films in beauty, color and grandeur. We can't wait to see the sequels!


Pinus bungeana (lacebark pine) is a character actor, ready to grab the leading role in summer

There are many parallels between a movie director and a gardener. Think of your garden as a movie set which has 365 different scenes to be viewed each year. Each daily scene must be planned, staged and completed, to ensure a year of viewing pleasure. Just as with a movie, you don't want every scene to be a high intensity “action sequence”. How about some quiet or romantic interludes? You certainly want to have something worth admiring each day of the year, especially your garden's most select vistas. There are days requiring a special view to celebrate an important occasion. Treat those dates as critical scenes, which require research, advance planning and special attention to put you in the running for your garden Oscar!


Tsuga canadensis var. pendula works well with a supporting cast of extras, including hostas, ferns and Brunnera

We'll jump into this garden movie mid-year, as summer is fully upon us. The new growth flush has finished, the conifers are now sharing the spotlight with others, yet still command attention. Their wide range of colors, textures, shapes and sizes make them an indispensable part of scene composition. If you, as director, are careful to provide the drainage (sometimes mounds or raised bed are a necessary part of the set) and the sunlight they require, they are generally reliable performers in summer and work well with other companion plants with similar cultural requirements. The weeping hemlock featured above underplays its role as the dominant character in the scene, allowing the supporting cast to shine in a shady location.


Larix kaemferi 'Pendula' and Picea pungens 'St. Mary's Broom' claim center stage in summer, assisted by supporting cast

You will need some character actors, stars, supporting cast, bit players and likely some “movie props” in your garden drama. Some of your potential actors might be high maintenance divas and you will have to decide if the effort is worth their contribution. Shapes, sizes, textures, and growth rate are important elements in the cast selection process. Just as actors must have “good chemistry” to successfully perform together, you must similarly pay attention to cultural requirements to achieve good outcomes as you mix your conifers with companion plants. Finally as part of your ongoing maintenance, you may find the need to retire some actors and bring in some promising new talent.

As the film rolls through the summer scenes, the conifers continue to add value and texture. Go out and view your own garden 'movie' and hone your directorial talents. Not all the at-home drama is playing on Netflix these days!


Pinus parvifloras ‘Tanima no yuki’ and ‘Kinpo’, Hylotelephium cauticola ‘Lidakense’ and Ophiopogon planiscapus 'Kokuryu'

In the late-summer shot above, the conifers provide a cooling influence to the more dramatic black mondo grass and pink-flowering sedum. All of these actors come to us from Japan, and the staging has been designed accordingly.

Coming to a blog near you in September: Autumn!

By Jerry Kral
July 23, 2020

Clematis pitcheri in Cryptomeria japonica ‘Araucarioides’

Most of us wouldn’t dream of messing with a wonderful conifer specimen. They sit there in the sun regaling us with their colorful foliage or unique texture. Some stand alone or are nicely grouped with complementary conifers. Often, a non-conifer may be invited to join the party. What else is needed? May I suggest a little “bling”?

I don’t mean going around adding necklaces, rings or frosting conifer foliage with sequins. I’m referring to botanical jewelry such as a non-obtrusive necklace of a delicate vine. A properly used vine can add interest and draw even more attention to a specimen conifer or conifer grouping, such as in the image above, where the 'Aurea' Japanese cedar wears some Clematis finery.

Vines used as conifer necklaces need to meet some requirements. They must be delicate enough not to smother the plant. They must not climb by twining so they can be easily removed at the end of the growing season and not add extra snow or ice load in the winter. I’ve enjoyed playing with one vine that is rarely seen and meets all the requirements


Clematis pitcheri in Picea abies ‘Hillside Upright’

Clematis pitcheri (purple leather flower) is native to the Midwest, ranging from Iowa and Illinois to Texas. Pruning is not an issue. It is a perennial vine, freezing to the ground at the first killing frost. Just cut it at the base after the top freezes. In spring it will send up 3-4 sprigs that can eventually clamber 15-20 feet in a season. These emerging sprigs are brittle, so support them until the petioles clasp onto a conifer branch. Each vine shows little tendency to branch so it is unlikely to smother any conifer, certainly not the Hillside Upright Norway spruce.


C. pitcheri on Picea abies ‘Pusch’ The vine is rooted 15’ away!

The small, purple, pitcher shaped blossoms are continuously produced from late May until frost. There are no selected cultivars. Species variation produce flowers from light purple to dark purple. Some will even show white edges on the petals. The following three photos show some of the flower color variation within the species:


Clematis pitcheri with deep mauve flowers

Clematis pitcheri flowers with a redder tone

A bumble bee inspects the soft, pink and cream flowers of Clematis pitcheri

Since the vines are mostly unbranched and don’t twine, they can be easily pulled out of even the most delicate conifer. This species is sun loving, so will clamber on the top of even the smallest dwarf conifer. Once established, it is quite drought tolerant. And, if that isn’t enough, being a small flowered clematis, it is almost immune to clematis wilt! And, even better, rabbits and deer may find it slightly poisonous.

C. pitcheri likes well drained soil with consistent moisture. It is especially fond of alkaline soils, however, mine do very well in slightly acid soil mulched with pine bark. I even get 3-4 seedlings a year.


C. pitcheri scrambling atop a Pinus strobus ‘Minuta’

The purple flowers go beautifully with the blue-green needles of the Pinus strobus 'Minuta' (Minuta Eastern white pine).


C. pitcheri on Picea pungens ‘Glauca Procumbens'

The lighter flowers and the baby-blue needles of Picea pungens 'Glauca Procumbens' produce a softer look.


C. pitcheri on Pinus mugo ‘Paul’s Dwarf’

Paul's Dwarf mugo pine is a garden stalwart but is not above being bedecked with finery!

I’m sure there are many other tree and shrub friendly vines that can add that bit of bling to a specimen conifer and interest to your garden. Purple leather flower is so user friendly I have not tried any others, but you should investigate what vines grow in your climate that have the same habit. I usually have 2-300 visitors tour my gardens each year, and my use of this unique clematis seems to surprise and delight even the most jaded garden visitor. So do your thing and add some bling!

Jerry Kral is a longtime ACS member who gardens in Rochester, NY.

By Web Editor
February 1, 2020

Beneficial fungi help conifer growth, hardiness, and disease resistance. Read on to find out if they are for your garden.

Fruiting bodies (mushrooms) of a mycorrhizal fungus in a fir transplant bed. Photo: John H. Ghent, USDA Forest Service, Bugwood.org

Mycorrhizae are a subject which generates a lot of discussion among people who grow conifers. Whether they are foresters, nursery managers, Christmas tree growers, or conifer gardeners; everyone seems to have an opinion on mycorrhizae.

With an increasing array of mycorrhizal products on the market, the discussion around mycorrhizae and their importance in conifer health continues to intensify. Below are some key things conifer enthusiasts should understand about mycorrhizae.

What are mycorrhizae?

Mycorrhizae are associations between fungi and plant roots. The term mycorrhizae comes from the Greek mykos “fungus” and riza “roots”. Mycorrhizae are an example of a symbiotic relationship between two organisms, in which both organisms benefit, referred to as a mutualistic association. In the case of mycorrhizae, the fungus gets energy in the form of photosynthates from the plant. The plant, in return, gets an increased ability to absorb water and nutrients from the soil, resulting in more efficient resource uptake.

Conifers may benefit from the presence of endomycorrhizae. Photo: Robert L. Anderson, USDA Forest Service, Bugwood.org

How many types of mycorrhizae are there?

Mycorrhizae are generally described as one of two types; ectomycorrhizae and endomycorrhizae. In ectomycorrhizae, fungi produce threadlike structures (hyphae) which form a network of cells in the intercellular spaces of the root (Hartig net), but do not penetrate the cortical cells of the plant root.

Ectomycorrhizae also form a sheath of hyphae around the outside of the root (mantle). In endomycorrhizae, fungi form structures (arbuscules) which penetrate inside the roots of the host plant, most common in forest trees. Although both types of mycorrhizae increase nutrient uptake, endomycorrhizae have been specifically linked to improved phosphorus nutrition. There are numerous fungal species involved in both ecto- and endo-mycorrhizae, and host fungus associations are often species- or genus-specific.

What kinds of trees are infected by mycorrhizae?

Most land plants, including conifers in the family Cupressaceae (cedars), form endomycorrhizal associations. Ectomycorrhizae only occur in about 10% of plant families, but they are important for conifer growers because all members of the pine family including true firs (Abies), spruces (Picea), pines (Pinus), Douglas-fir (Pseudotsuga), and hemlocks (Tsuga) form ectomycorrhizae.

Ectomycorrhizal root tips of red pine showing characteristic two-part split ends (bifurcations). Photo: Robert L. Anderson, USDA Forest Service, Bugwood.org

Can I tell if my trees are mycorrhizal?

Structures associated with endomycorrhizae fungi are not visible with the naked eye and require specific microscopic examination; however, it is often possible to determine if roots are infected with ectomycorrhizae by visual examination. The root tips of conifer roots infected with mycorrhizal fungi may split off into pairs at the ends, referred to as bifurcations.

In other situations the hyphae of the fungus form visible matting (mycelia) on the roots. Also, the fruiting bodies of many mycorrhizal fungi are mushrooms, so their presence can also indicate that conifers are mycorrhizal.

Does artificial inoculation with mycorrhizae improve tree performance?

The beneficial association of mycorrhizal fungi and tree roots has been known for decades. Some of the most classic examples of the essential role of mycorrhizae in tree growth and development come from attempts to establish conifers as exotics. For example, early efforts to establish Monterey pine (a North American native) in Australia and New Zealand failed due to a lack of appropriate mycorrhizal fungi.

Similar failures of afforestation efforts in grassland areas have also been attributed to lack of mycorrhizae. Numerous studies of artificial mycorrhizal inoculation of trees have found significant benefits including increased survival, growth, drought hardiness, nutrient uptake and disease resistance. However, results of artificial inoculation are often highly variable, and many studies show only modest benefits or no improvement at all compared to plots or trees not inoculated.

The thread-like vegetative structures (hyphae) may be visible to the naked eye. Photo: Paul A. Marietta, USDA Forest Service, Bugwood.org

If mycorrhizae are essential for conifer growth and development, why doesn’t mycorrhizal inoculation always provide a benefit?

There are several reasons why inoculating with mycorrhizae may not improve tree performance. First, in areas near native woodlands, native mycorrhizae spores are likely already present in the soil. For example, European researchers inoculated Norway spruce and Scots pine seedlings with three known mycorrhizal fungi prior to field planting. After three years, the only fungi they could isolate from the trees were native types, not the ones they used for inoculation.

It is also important to remember that mycorrhizal fungi are host-specific. In other words, trees species and fungal species have to be a match. Since many conifer gardens may contain dozens of tree species, it is possible that one source of inoculum will not work on all species. In a study in Canadian nurseries, researchers used six types of fungal spores to inoculate lodgepole pine, white spruce, black spruce, Scots pine and Siberian larch. Some fungal types showed consistent benefit, but two types did not improve seedling growth compared to un-inoculated controls.

Trees may also fail to respond to inoculation due to problems with the inoculation procedures. In some conifer nurseries, beds are inoculated using soil from local woodlands, which presumably contains mycorrhizal spores and mycelia. More commonly, bareroot and container nurseries now use commercially produced spores or inoculum containing ground mycelia.Inoculum can remain viable for months or even years when stored at room temperature or refrigerated, however, viability will ultimately decrease with age or extreme storage conditions.

Lastly, inoculation may not improve tree performance if site resources are not limiting. Conifer enthusiasts often fertilize and irrigate their gardens, potentially limiting the benefit of improving nutrient or water uptake by adding mycorrhizae. In addition, high nutrient levels can also reduce the success of mycorrhizal colonization. High soil phosphorus levels, for example, can inhibit endomycorrhizal colonization.

Container-grown Douglas-fir with (left) and without (right) mycorrhizal inoculation. Photo: Mycorrhizal Applications, www.mycorrhizae.com

Should I inoculate my trees with commercial mycorrhizae?

For most conifer gardeners the answer is, “Probably not.” As noted above, mycorrhizal spores are likely already present in your soil. Moreover, it is also highly likely that the seedlings and transplants you purchase from your nursery supplier are already colonized by mycorrhizal fungi when you receive them. For conifer gardeners who live in areas where few conifers are present, there may be situations where native mycorrhizal spores are not present, or are present in low quantities, and artificial inoculation may be beneficial. This could include gardens in the Great Plains, or planting in new developments where top-soil has been removed.

Because of the complexities associated with mycorrhizae, it is difficult to predict with 100% certainty, under which situations inoculation may or may not improve performance. Conifer growers who wish to experiment with mycorrhizae should keep several points in mind: keep careful notes on species, stock types, source nursery, and inoculum source and growing conditions. As noted, there is a good likelihood that your plants and/or soil already contain mycorrhizae, so it’s important that you are able to convince yourself that that expense and effort of adding them are warranted.

Conifers grown in containers are inoculated with mycorrhizae. Photo: Joseph O’Brien, USDA Forest Service, Bugwood.org

Where can I learn more?

The USDA Forest Service “Reforestation, Nurseries, and Genetics Resources” website (www.RNGR.net) has several excellent resources on mycorrhizae under their “Publications” section. Two particularly good references are Chapter 20 in the Bareroot Forest Nursery Manual, “Mycorrhiza Management in Bareroot Nurseries” by Randy Molina and James Trappe and Volume 5 of the Container Nursery Tree Nursery Manual, “The Biological Component: Nursery Pests and Mycorrhizae” by Michael Castellano and Randy Molina. The latter chapter includes one of the most comprehensive lists of mycorrhizal incoculum × conifer species matches available.

References:

Castellano, M.A. & Molina, R. (1989). Mycorrhizae. IN: Landis, et al. The Container Tree Nursery Manual. Vol. 5. USDA Forest Service Agric. Handbook 694. p. 101–167.

Khasa, P. D., Sigler, L., Chakravarty, P., Dancik, B. P., Erickson, L., & Mc Curdy, D. (2001). Effect of fertilization on growth and ectomycorrhizal development of container-grown and bare-root nursery conifer seedlings. New Forests, 22(3), 179–197.

Menkis, A., Vasiliauskas, R., Taylor, A. F. S., Stenlid, J., & Finlay, R. (2007). Afforestation of abandoned farmland with conifer seedlings inoculated with three ectomycorrhizal fungi—impact on plant performance and ectomycorrhizal community. Mycorrhiza, 17(4), 337–348.

Molina, R., & Trappe, J. M. (1984). Mycorrhiza management in bareroot nurseries. In Forestry Nursery Manual: Production of Bareroot Seedlings (pp. 211–223). Springer Netherlands.

Perry, D. A., Molina, R., & Amaranthus, M. P. (1987). Mycorrhizae, mycorrhizospheres, and reforestation: current knowledge and research needs. Canadian Journal of Forest Research, 17(8), 929–940.

Text by Dr. Bert Cregg. This article was adapted from a related article published in the Great Lakes Christmas Tree Journal.

Dr. Bert Cregg is an Associate Professor in the Departments of Horticulture and Forestry at MSU.

By Ronald Elardo
September 6, 2019

Learn about the unique phenomenon of conifer cresting.

Fasciation in ‘Cristata’ refers to the banded or bundled growth at the tips of its branches

Dan Gurney submitted the photo of ‘Cristata’ to the Conifer Quarterly. You would agree that it is most intriguing. When I looked up Cryptomeria japonica ‘Cristata’ (cristate Japanese cedar) in the ACS conifer database, what I found spurred me to investigate the possible reasons for this phenomenon, known as cristation, or fasciation.

The cultivar name ‘Cristata’ comes from the Latin adjective cristatus which, in turn, is related to fasciate. The noun, fasciation, describes the banded or bundled growth at the tips of the branches of a plant. Cristate means having a crest-shape, like the cockscomb on the head of a rooster.

Scientists believe that cristation, or fasciation, results in the tip of the branch growing outward, rather than growing farther along the stem. They attribute this fan-shaped growth to hormonal imbalance, insects, diseases, or physical injury to the plant.

A Natural Occurrence in Conifers

The strange growth is most likely caused by phytoplasma, which are bacterial parasites of the phloem tissue and of the insect vectors involved in plant-to-plant transmissions. The fan-shaped protuberance appears on many genera of plants: cacti, roses, and beefsteak tomatoes, to name but a few.

As a consequence, since cristation is a cellular deviation, it may be the result of a genetic predisposition inherent in the plant, which causes division of growth and consequently that characteristic spreading-out at the tip of the branch. It would be interesting to hear from you, the membership, on this subject. In the meantime, a Google search will yield an array of beautiful pictures of plants with fasciation and cristation.

A Hidden Conifer Gem in Woodinville

Dan Gurney reported that this particular cristate Japanese cedar is 50–60 years old and 50-feet tall. It has been growing in Woodinville, Washington, 20 miles northeast of Seattle at the JM Cellars Winery of Peggy and John Bigelow. The previous owners of the winery, Jan and Smitty Smith, were conifer collectors.

In the ACS conifer database, one can see an excellent closeup of the cockscomb-like growth on a ‘Cristata’ specimen at the Cox Arboretum and Gardens in Canton, Georgia.

Photograph by Dan Gurney.

Dan Gurney is co-owner of Gardening Artist with his wife, Mary Warren. They reside in Seattle.

By Mary Coyne
November 2, 2019

Dr. Mary Coyne speaks on the challenges and rewards of watching over the Wellesley College Conifer Reference Garden.

A view of by the Conifer Reference Garden. Photograph by Wellesley College Horticulturist, David Sommers

Passersby say, “It looks great!” As of 10 years I ago I thought it would always “look great,” but I had a lot to learn. It seemed like an easy project – build a wall, bring in new soil, pick out some plants, plant the dwarf and miniature trees, stand back and watch them grow. Nothing to it.

Ten years later at the Wellesley College Conifer Reference Garden, I know better and I thought that some of my experiences might be helpful and possibly amusing to those in the know. The Wellesley Conifer Reference Garden contains mostly dwarf and miniature conifers and is located on a slight upward slope extending back from a 3-foot high wall, running about 60 feet in length.

Watering Solutions for a Conifer Reference Garden

Мy first problem was water. I had insisted on running two water lines to the top of the embankment above the wall, but setting out hoses and sprinklers was taking too much time for the greenhouse personnel.

So, I considered a drip hose for the area and found a wholesale dealer for RainBird equipment nearby. The dealer measured the water pressure for the extensive lines and determined that because the area was so large, it had to be divided into three sections. The downside of this arrangement is that each section took about 5 hours to water and often the personnel went home and forgot to turn the water off.

To solve this problem, I installed three elevated spray heads so the workers could see if the water was still on. Newly planted trees needed more frequent watering, a task given to the summer student interns. I oversee and maintain this garden mostly by myself with the help of intermittent volunteers, but since I am away most of the summer, I must depend on others to follow through with watering.

Yucca sprouts in the Wellesley College Conifer Reference Garden. Photograph by Dr. Mary Coyne

Yucca Control within a Conifer Reference Garden

One of the original plants scattered across the dry embankment before the area was rescued for a conifer garden, was a yucca. About a month after it was removed, I noticed some shoots erupting in the area. Since the area was unplanted, I dug down about 2-3 feet and uncovered a massive root about 3 inches in diameter and 18 inches long. I was impressed and felt relieved that I had solved the problem.

Ten years later I am still fighting that yucca. Sprouts began appearing again and were moving slowly along the planting bed. Stories on Google were not encouraging, but I finally followed what appeared to be a successful procedure. I let one plant grow up somewhat, clipping off all the others. I wrapped the leaves of this plant with cotton batting soaked in RoundUp, bent the leaves over into a stainless-steel pan with more Roundup and sealed it with plastic.

One month later, the plant was still alive! Not good. A year ago, I let another sprout grow that had popped up outside the garden, hoping that all the plant’s energy would go there and the other small sprigs would die out. It seemed like this was working. But last summer there were sprouts again. I have a life-long job snipping yucca sprouts!

Sawfly larvae munching on Pinus x densithunbergii ‘Jane Kluis’ in the Wellesley College Conifer Reference Garden. Photograph by David Sommers

Managing Sawfly Populations in a Conifer Reference Garden

A good friend of mine in the American Conifer Society always told me not to buy two-needle pines, but never said why. Now I know why. Along the stairway through the garden there were four Pinus x densithunbergii ‘Jane Kluis’ which were growing quite well.

One day one of the greenhouse personnel brought me over for a look at the front plant. Needles were missing and on closer inspection, I saw that it was covered with sawfly larvae. We grabbed our gloves and pulled them off into a bucket of soapy water.

This happened each year. Last year the other three trees had to be replaced as they were in bad shape even though we had been pulling larvae off them each year. Down at the other end of the garden, I also found a dead, chewed-up Pinus banksiana, another two-needle pine. Two of my replacements along the stairway were Pinus heldreichii ‘Banderica‘, a two-needle pine.

Google searches indicated that this pine is not a primary target, and another in the garden is good so far. The Botanic Gardens is a pesticide-free environment, so we’ll see. However, our very dry summer of last year took its toll on the three replacements in spite of assiduous watering.

Adding Variety to your Conifer Reference Garden

The Reference Garden has about 76 living conifers, composed of 18 genera including Ginkgo and Ephedra and several species of Chamaecyparis, Juniperus, Picea, and Pinus. Over the nine years, I have had to replace about 37 trees, either because they had died over the winter (23%), or they were not in good enough display condition (10%). I have two holding areas for replacements, one at the College and another at home where I can watch them more closely. Several at home are recovering patients which may eventually be replanted. It pays to deal in dwarfs and miniatures!

The garden is on a major pathway for faculty, staff and students entering the Science Center, and the conifers provide good winter interest. To introduce a little color for both spring and fall, I have interplanted the area with spring bulbs, ephemerals, and perennials as well as several fall bulbs and rock garden plants in the scree.

The choice of bulbs include

• Anemone blanda

• Chionodoxa forbesii

• Colchicum bornmuelleri

• Erythronium ‘Pagoda’

• Eranthis hyemalis

• Galanthus nivalis

• Cyclamen hederifolium

• Iris reticulata

• Muscari armeniacum

• Narcissus bulbocodium conspicuous

• Trillium grandiflorum and T. nivale

These, as well as wild tulips, has outwitted the chipmunks so far, but they continuously burrow in and around the stone wall, and some bulbs do disappear.

Rock garden plants have variable survival rates so there are always replacements, and some have had to be removed completely because they turned out to be invasive. In the last couple of years, I have also started a couple of hypertufa troughs with miniature conifers and placed them in a protected area.

I am concerned that they might easily be transported away so I keep them out of the main pathway. Extra additions, of course, make more work, but they do make the garden more interesting.

Routine Tasks at a Conifer Reference Garden

Each conifer receives a professional label which has a black background with white printing. Over the winter, there are always a few labels that disconnect from their stem and must be found, cleaned, and reattached with superglue (my solution).

Even the Reference Garden sign needed such repair, probably because children love to walk along the wall and may have knocked against it. New conifers and herbaceous plants are hand-labeled; many labels are missing by spring and are also replaced.

Every other year new mulch is added to the garden, but, because there is a slight slope down to the wall, the mulch usually accumulates at the bottom by the end of the winter. This necessitates cleaning out around all the conifers in the spring so the trunks are not submerged in piles of mulch.

Replacements, watering, and mulch all require funds, and grants from the Conifer Society have supported the conifer related costs. Wellesley College Botanic Gardens provides additional funds for the non-conifer plants.

Map of Wellesley College Conifer Reference Garden. Screen shot of map in ESRI Collector App by Dr. Mary Coyne

GIS Technology and Conifer Reference Gardens

Being a Type-A personality I wanted to keep track of all the plantings: their location, health, and growth rates. I started by mapping the Reference Garden with a CAD program with layers for conifers, bulbs, and herbaceous plants.

However, once the College installed a server for ArcGIS (GIS stands for geographic information systems), I mapped out the Reference Garden and added it to an archived database for all the Botanic Gardens trees. A new Collector app for ArcGIS now lets me do an annual inventory of the trees in the Reference Garden using my iPad or Phone.

These data are connected to each tree in the ArcGIS Map and include height, width, health, presence of label, comments on work to be done, and a photo. The mapping allows me to assess where my greatest losses of plants occur, which species have survival problems, as well as growth rates.

Anyone interested in pursuing the use of ArcGIS for mapping gardens should go online to American Public Gardens GIS website and Alliance for Public Gardens GIS for further information and for access to a GIS template for public gardens.

The Rewards of Watching a Conifer Garden Grow

As a retiree, I have found that working in the garden provides a great social payback. On weekends, I interact with local and international visitors, and during the week I often am called upon to give an extemporaneous presentation to student groups at all educational levels.

College staff and faculty are always passing by and remark how much they enjoy seeing what is growing and blooming. It is satisfying to realize how so many people enjoy the garden. As a long-time gardener of perennial plants, I should have realized that keeping up a Reference Garden would be work. However, I never realized that, in addition to weeding, there would be so many other annual jobs.

How am I going to convince someone to eventually replace me? Maybe they will enjoy it as much as I do.

Dr. Mary Coyne is Professor Emerita at Wellesley College. She may be contacted at mcoyne@wellesley.edu.

By Mary Warren
March 13, 2021

Using art and math to create a garden design might seem like artificially superimposing incompatible sets of rules on plant placement in garden beds. However, in concert, art and math can actually provide good mechanics for building a garden that will be a joy to behold. In this article, the experienced and the hobby gardener alike will find suggestions for a successful layout that will also aid in the best plant choices, all based on artistic and mathematical principles.

Coulter’s pinecone

To begin, one doesn’t have far to look to find a planting grid. Nature provides a few. The structure of the fronds of a fern or the scales of the Coulter’s pine (Pinus coulteri) can suggest a garden diagram. Follow the downward spiral of the cone’s scales or the fern’s unfurled fronds, and a three-dimensional, conical display emerges. If plants are placed to mimic the swirl, with attention paid to the distance between plants, the result is that each plant is simultaneously visible and also contributes to the entire scene. When painting in oils, this layering is referred to as working lean to fat, building pigments from the bottom layers up and across the canvas. When applied, this principle creates a garden with many levels. The garden becomes a living painting as its plants layer up and across the bed.

Logarithmic spiral.

Gardeners who choose the pattern of the scales of the Coulter’s pinecone or the furls of the fiddlehead fern are actually using what the mathematicians dubbed “The Golden Ratio”. To put it simply, the gardener must give plants space, according to growth rates, so that they don’t spoil their neighbors by growing into them. One can find conifer growth rates and sizes in the American Conifer Society’s Conifer Database (conifersociety.org). Other plant specifications are available on the Internet. Knowing how large plants will get assists in choosing the right ones for the space the garden affords.

In selecting plants for the garden, color, texture, and shape provide visual stimuli, evoking a sense of beauty that is unique to each person. For one gardener, the arms of Cupressus nootkatensis ‘Green Arrow’ (Green Arrow Nootka cypress) might appear too zigzagged and visually disruptive. For another, ‘Green Arrow’ symbolizes a skyward motion, a reaching-up, like an arrow shot into the sky. Another gardener might prefer more conventionally shaped conifers like Picea glauca var. albertiana ‘Conica’ (Dwarf Alberta spruce), with its classic Christmas tree shape. Regardless, the choice of plants expresses the gardener’s individuality and personal vision.

‘Green Arrow’. Photo by Ron Elardo

In addition to the proportions suggested by the Golden Ratio, other possible bed designs can be inspired by both art and math. Buddhist mandalas, for example, combine both art and math and are meant to portray perfection. A mandala can be simple or complex. A Google search will yield a plethora of examples. From Western art, there is an even simpler mandala, based on Leonardo da Vinci’s Vitruvian Man, man within a circle within a square, the so-called “squaring of the circle” (Carl Gustav Jung, Symbols of Transformation). From my design education and experience, modifying the square shape of this model to create a rectangular-shaped bed affords the gardener a much more flexible layout plan.

Da Vinci’s Vitruvian Man.

The ancient Greeks applied “golden/sacred numbers” in the creation of the great architectural works they dedicated to their gods. The mathematically precise, rectangular spaces between the columns in the Temple of Athena Nike, at the top of the Acropolis in Athens, can be copied on a smaller scale in the construction of garden beds. Those rectangular shapes can accommodate more easily even or odd numbers of plants than square beds can. Avoid beds planted in rows. They lose dynamic energy and look like a production nursery. Lean to fat planting, as described above, produces a soft and relaxed reaction as the eye begins at the top of the design, pans downward to a flared-out base, and then around the bed back up to the top.

Columns of the Temple of Athena Nike.

A fundamental rule in sketching and painting is to refrain from working solely from one corner outward. Gardeners should shape the garden from all directions simultaneously. They should engage with the entire planting area, in the same way that a tree is pruned aesthetically. The tree is simultaneously viewed from all angles. Gardeners should strive for the best possible three-dimensional look, recognizing that plants will inevitably steer their own way. Height, transparency, density, and color may require particular placement for best effect.

One last consideration is the inclusion of different soils, rock formations, structures, and figurines into the garden. These elements may require rethinking plant placements, while maintaining balance and the impact of a well-rounded display.

When modifying existing gardens, rely upon the inspiration art and mathematics can provide. Those mechanics will provide a framework for design decisions. The purpose in utilizing time-worn methods is to proDuce a garden that will refresh both the eye and the soul.

Enjoy this journey in artistic and mathematical design.

Mary Warren is the Owner of Gardening Artists located in Seattle, WA. She holds a Bachelor of Fine Arts Degree from the California College of Arts and Crafts and a Master of Fine Arts Degree in Sculpture from the University of Washington. She has been gardening since she was four years old, when her mother showed her how to plant fragrant sweet peas.

By Web Editor
November 29, 2019

Follow a Raleighite's adventure in growing his conifer garden.

A dwarf California red fir (Abies magnifica `Nana')

According to conventional wisdom, the only fir which will grow in North Carolina outside of the mountains is Abies firma. Conventional wisdom also suggests that Abies firma is not a particularly attractive tree. About eight years ago, however, as I was trying to establish the most attractive landscape possible, it was clear that I needed to include Abies plants, if possible, and I could not find evidence, anecdotal or otherwise, which would verify these myths.

Therefore, I decided to give it a go and, in 2007, began planting every Abies species I could get a hold of which I thought might have a chance in our hot, humid climate. In 2008, I began finding Abies grafted onto Abies firma and nordmanniana and I bought almost as many as I could find over the years. My interest in growing Abies has also led me to other notable gardens in the area where firs are growing. Thus, I now have gathered quite a bit of anecdotal experience about growing Abies in central North Carolina. The purpose of this article is to share my experience, to open up more discussion and trialing of Abies, and to motivate more growers to graft firs on Abies firma rootstock.

Conifer Growing Challenges in the Southeast

Raleigh certainly does not seem like a great place to grow firs. The soil is the traditional southern red mud: slick when wet, hard as a brick when dry, and drains poorly all the time. The weather is hot and humid, and the summers are long. We typically get long stretches, up to six weeks, during the summer, when the low temperatures do not dip below the low 70’s. It is not rare to have months where the highs stay in the upper 90’s to over 100. Summers usually last for four months with hot temperatures beginning no later than mid-May and lasting through mid-September. This climate is certainly not the cool dry mountain habitat where I think of firs thriving.

Nonetheless, the allure of firs is strong. No other genus offers the same bright green soft foliage with the sparkling silver undersides of the needles. Keteleeria comes close, but can’t rival the beauty of Abies with its perfectly symmetrical form and tiered layers of branches. Then Abies offers so many spectacular cultivars with weeping and pendulous forms and a broad range of green, yellow and blue hues. The cones of many firs are also particularly noteworthy; most have fragrant needles (when crushed); and some even have fantastic bark (e.g. Abies squamata). The desire to grow Abies is probably obvious to any member of the American Conifer Society.

A view of momi firs (Abies firma) in a conifer garden

Preparing for a Conifer Garden in a Hot and Humid Climate

Despite the climate and soil challenges, I remain surprised that there is not more available information about growing firs in the Southeast. There is a strong horticultural tradition in North Carolina with the mountains’ Christmas tree industry and particularly in Raleigh, the home of North Carolina State University. The late NC State horticultural professor, JC Raulston, is credited with originating the idea of grafting firs onto Abies firma rootstock, but it is still extremely difficult to find even first-year grafts available for purchase in Raleigh or elsewhere in the Southeast.

Eight years ago, even with limitless information and sharing of ideas on the Internet, I could find no specific information about the survival of any fir other than Abies firma. Even today, Tom Cox and John Ruter’s recent excellent book, Landscaping with Conifers and Gingko for the Southeast, is the only publication I am aware of which discusses growing this genus with any degree of thoughtfulness.

My story begins in the spring of 2005 when my wife, two small kids and I moved to Raleigh for my work. After moving five times in nine years, we wanted to find our long-term home. We bought a house near downtown Raleigh on just under a half-acre lot which was covered in loblolly pines which had been haphazardly scattered across the backyard. These trees were messy, unattractive (in this setting) and their placement made it hard to throw balls and play games with the kids, and, as a result, we had them removed before we moved in August of 2005.

Starting a Conifer Garden in the Southeast

I immediately went about correcting this insult to Mother Nature by planting trees in more suitable positions in my yard and did as much research as I could to find the best and most beautiful trees possible. The Internet was quite helpful, and I also discovered Michael Dirr’s Manual of Woody Landscape Plants in 2005. I read it cover to cover and searched long and hard to find trees like Emmenopterys henryi, Davidia involucrata, Stewartia monodelpha, and Cornus controversa ‘Variegata.' In 2005, since I had a long timeline, I was willing to start with some small trees, but I wasn’t willing to take much risk on a tree’s survival. For the first several years of my yard, I did not include conifers since I was under the impression they would not do well.

In 2007, my family (now three kids) took a walk through nearby Duke Gardens. I was particularly impressed with a pendulous form of Picea omorika as well as a specimen of Sequoia sempervirens ‘Henderson Blue,' and the “game” in my yard suddenly changed. During the next several years, my “yard” transitioned to a “garden” as I included conifers. Other factors were also coming into play. My plants required quite a bit of water, and we were in the middle of a severe drought. Restrictions on irrigation were instituted in Raleigh, and, as a necessity, I had a well drilled in our yard so that I could irrigate as much as needed (all my woody plants are on drip irrigation).

I also realized that these conifers, with which I had been fascinated, would benefit from better drainage. I began bringing in the first of what would be hundreds of cubic yards of specially mixed topsoil with 30% PermaTill to simulate Rocky Mountain soil the best I could. My wife was really patient with me as we seemed continually to have piles of topsoil in our driveway for a couple of years so that I could make elevated planting beds. The kids loved to climb these alluvial hills, spreading dirt everywhere, including inside the house. Finally, in 2010, my wife and I added a covered porch to the back of our house so that we could enjoy our “garden” (she still calls it our yard). I took the occasion of this renovation project to have stacked stone walls added to border the elevated beds and also to create stone walkways which would wander around the yard. Thus, a reasonably good setting for conifers was created.

The conifer, ‘Glauca Nana’ Min fir (Abies recurvata ‘Glauca Nana’) from China

Sourcing Conifer Seedlings from Warmer Regions

In 2007, I began ordering seedlings of firs from China and the Mediterranean region, since these areas seemed to have heat similar to ours. Most of these species seemed pretty obscure, and I thought it was possible that they had not been grown here before. I did realize that JC Raulston had access to just about every plant in the world, but thought it was possible that he may have gotten distracted from experimenting with Abies. As mentioned above, I could certainly find no record or person who remembered his growing some of these obscure species.

When my first Abies plants arrived, it turned out that some had been grafted (Abies nebrodensis, Abies cilicica) presumably onto Abies balsamea root-stock. I also bought an Abies koreana ‘Horstmanns Silberlocke,' beautifully grown in a three gallon container from a reputable grower, but likely grafted onto Abies balsamea, as well. Each of these “heat tolerant” firs which had been grafted were dead by late June of 2007—consistent with conventional wisdom! I also bought Abies bornmuelleriana, Abies x borisii-regis, Abies cephalonica, Abies homolepis, Abies koreana, Abies numidica, Abies chensiensis, Abies fabri, Abies delavayi, all of which eventually died.

During this period I also bought seedlings of Abies firma, Abies recurvata var. ernestii, Abies pindrow, Abies holophylla, and, a year later, Abies nordmanniana, all of which remain alive and appear to be quite healthy. I did lose an Abies nordmanniana and I also chose to remove a living Abies sachalinensis var. mayriana. It was a beautiful little tree, but it appeared to be struggling while my other seedlings appeared to be thriving. Impatience compelled me to yank it out after it had survived five summers. It also helped that I had one grafted onto Abies firma rootstock.

Success Stories from a Conifer Garden in the Southeast

Over the last 7 years, I have been able to make some observations about these plants. I realize that my experiment with these firs is far from scientific. First of all, I bought only one of most of these firs, and I also had to rely on the seller for their true identity (it’s hard for me to distinguish young specimen of Abies cephalonica from Abies holophylla). The planting conditions also varied in terms of sun exposure, drainage and watering. Thus, my comments on these individual species are anecdotal.

Nonetheless I am particularly impressed by Abies recurvata and Abies holophylla. Both are growing vigorously and have added almost 1' of growth each of the last two years. The Abies recurvata is particularly impressive since it was not planted in particularly special soil, and its root zone has definitely extended into the native North Carolina clay. However, I’m not convinced that either of these plants offers much which visually distinguish it from Abies firma, but it is possible the whiter undersides of the Abies holophylla needles may make it more attractive. I have seen several very attractive older specimens of Abies holophylla at the Arnold Arboretum in Boston. Abies firma grows quite well for me and I find it can be a very attractive tree.

A conifer seedling, Shensi fir (Abies holophylla) growing since spring 2008

I have read observations that it is more “open-growing” than other firs, and that the course needles are unattractive. In Raleigh, we are fortunate to have quite a few mature Abies firma trees planted around town and most have beautifully tiered dark green layered branches. While I also prefer the firs with shorter, softer fragrant needles with white undersides, from a distance, large healthy Abies firma specimen are gorgeous conifers. Abies nordmanniana and Abies bornmuelleriana seem to be borderline here in Raleigh.

There are some large specimens of Abies nordmanniana about 30 miles northeast of Raleigh in Hillsborough NC, and Tony Avent is growing a beautiful specimen (about fifteen years old) of Abies bornmuelleriana at Juniper Level Botanical Gardens at his Plant Delights horticultural nursery about 15 miles southeast of Raleigh. I think these two species are particularly beautiful, but I have not had the greatest success with them. My one living Abies nordmanniana lost its leader last year, but still grew about 5" this year. It looks quite healthy, but I’m not confident that it’s thriving yet.

On the other hand, I am excited about the prospects of Abies pindrow. I bought one of these in the fall of 2007 and thought it was so attractive that I bought another the following spring. The long light-green, soft needles are beautiful, and the branches are pendulous with up-growing tips. They are native to what I’m told is a very wet part of western China. So far, our moisture hasn’t seemed to bother them as both of my seedlings seem to be quite healthy. I have one tree in mostly sun, and another in almost full shade, and both seem to be reasonably full in appearance. There does seem to be a question about the cold hardiness, but mine survived 8°F this past winter, and the specimen at the Arnold Arboretum in Boston is very healthy and has been growing for at least ten years.

Lessons Learned from a Heat-Tolerant Conifer Garden

While I was buying seedlings in 2007, I was also trying to find grafted firs which might survive our heat. Since firs grafted onto Abies firma rootstock were so scarce, I experimented with other rootstock. I bought quite a few on Abies nordmanniana rootstock. Three of my most beautiful firs are grafted onto Abies nordmanniana rootstock. I have four firs which have survived at least six summers in my yard. My Abies magnifica ‘Nana’ is probably the biggest surprise. This western North American fir is not one I would expect to do well here, but is full, colorful and grows at its expected rate of 3"– 4" per year.

My Abies nebrodensis x umbellata ((Abies homolepis x firma) x nebrodensis) certainly should be heat tolerant given its parentage and has not disappointed. It is almost 6' tall, has the most luxuriant soft blunt dark green needles with bright silver undersides and grows 6"– 8" a year. Similarly, my Abies pinsapo ‘Glauca,' which was bought as a 2' 6" B&B plant in spring of 2009 looks great, grew 12" last year, and is now about 5' tall. Unfortunately, I have had more failures than successes on Abies nordmanniana rootstock, even with plants which should be heat tolerant.

I have lost three Abies koreana ‘Horstmanns Silberlocke’, an Abies koreana ‘Aurea', an Abies pinsapo ‘Aurea,' an Abies numidica and an Abies concolor ‘Blue Cloak’ I thought would take our heat. I even bought several firs grafted onto Abies koreana rootstock. This reputable grower suggested that drainage was the key to success and that the Korean fir rootstock was heat tolerant. I planted all of them in perfectly draining soil, but all were dead by mid June of the year I received them. To their defense, however, these plants were all dwarfs which have also proven to be challenging even on Abies firma.

Text and photographs by Harrison Tuttle.

• Abies nebrodensis
• Abies yuanbaoshanensis
• Abies ziyuanensis
• Amentotaxus formosana
• Amentotaxus hatuyenensis
• Amentotaxus yunnanensis
• Araucaria angustifolia
• Araucaria luxurians
• Araucaria nemorosa
• Araucaria rulei
• Araucaria scopulorum
• Callitris sulcata
• Calocedrus formosana
• Calocedrus rupestris
• Cephalotaxus hainanensis
• Cephalotaxus wilsoniana
• Chamaecyparis formosensis
• Cupressus chengiana var. jiangensis
• Cupressus duclouxiana
• Cupressus dupreziana
• Cupressus dupreziana var. atlantica
• Cupressus goveniana var. abramsiana
• Cupressus guadalupensis
• Dacrydium comosum
• Dacrydium guillauminii
• Dacrydium nausoriense
• Fitzroya cupressoides
• Ginkgo biloba
• Glyptostrobus pensilis
• Juniperus barbadensis
• Juniperus bermudiana
• Juniperus brevifolia
• Juniperus cedrus
• Juniperus deppeana var. sperryi
• Juniperus gracilior
• Juniperus gracilior var. ekmanii
• Juniperus gracilior var. urbaniana
• Juniperus jaliscana
• Juniperus standleyi
• Keteleeria davidiana var. formosana
• Libocedrus chevalieri
• Metasequoia glyptostroboides
• Nothotsuga longibracteata
• Picea aurantiaca
• Picea chihuahuana
• Picea engelmannii ssp. mexicana
• Picea farreri
• Picea koyamae
• Picea likiangensis var. montigena
• Picea martinezii
• Picea neoveitchii
• Pinus amamiana
• Pinus armandii var. mastersiana
• Pinus culminicola
• Pinus massoniana var. hainanensis
• Pinus maximartinezii
• Pinus pinaster spp. renoui
• Pinus radiata var. binata
• Pinus rzedowskii
• Pinus squamata
• Pinus torreyana ssp. insularis
• Pinus torreyana
• Pinus wangii
• Podocarpus angustifolius
• Podocarpus capuronii
• Podocarpus costalis
• Podocarpus deflexus
• Podocarpus globulus
• Podocarpus hispaniolensis
• Podocarpus humbertii
• Podocarpus laubenfelsii
• Podocarpus longifoliolatus
• Podocarpus nakaii
• Podocarpus palawanensis
• Podocarpus pendulifolius
• Podocarpus perrieri
• Podocarpus purdieanus
• Podocarpus rostratus
• Pseudotaxus chienii
• Retrophyllum minor
• Sundacarpus amarus
• Taxus floridana
• Thuja sutchuenensis
• Torreya jackii
• Torreya taxifolia
• Widdringtonia cedarbergensis
• Widdringtonia whytei
• Wollemia nobilis
• Cupressus vietnamensis / Xanthocyparis vietnamensis

By Bill Blevins
April 19, 2020

Discover the lessons learned from a conifer collector about keeping a garden of evergreens.

The conifer, Picea abies f. pendula (pendulous form of Norway spruce)

I planted a Metasequoia glyptostroboides (dawn redwood) seedling in my Rochester, NY, backyard in 2007. My garden sported, at the time, dozens of other, newly-planted perennials, annuals, vegetables, and trees, but the dawn redwood made an impression on me.

It grew fast and was uniformly shaped like a pyramid, with no help from pruning. I learned that it was one of only a few deciduous conifers. Dawn redwoods have an interesting history, too, and, as a result, I thought it was just perfect. That plant became my tree, and I became a conifer collector.

A Conehead's Journey!

A few years later, my wife, Tracy, and I moved to Spotsylvania, VA. We bought a house on a two-acre lot in a new subdivision. The building contractor had planted an ornamental plum tree in front of the house, along with three azaleas, four nandinas, and a holly as foundation plantings in a row below the front porch.

The front yard was in full sun, with hard-packed, fill dirt that had been bulldozed smooth, and covered with a layer of straw and grass seed. Tracy started her new shade garden in the backyard, filling the edge of the woods with her favorite plants, such as hostas, pulmonarias, hydrangeas, viburnum, and many uncommon native trees.

Whenever we went plant shopping, I kept my eye open for unusual conifers. One day I said: “Since you’re gardening in the back, I’ll handle the front.” She agreed.

Learning from a Conifer Collection

I began planting conifers in 2013 – a lot of them. Since then, I have planted hundreds of other trees and plants in my part of the yard. Today, I would guess that our garden contains about 1,800 taxa.

Here are some things I have learned as a new plant collector:

• If you don’t have irrigation, locate plants that need a lot of water close to the house.

• The height, width, and spacing sizes printed on plant labels are an approximation. (Here is a tip: Attend your regional American Conifer Society meeting for the conifer tours. Also, the ACS Conifer Reference Gardens are a good way to see how big conifers mightultimately get in your yard.)

• Many botanical names and most family name printed on plant labels are either misspelled, or just wrong.

• Home improvement big-box stores display and sell lots of plants that are not hardy in the zone where the store is located.

• Once Japanese beetles find a plant they like, that plant is doomed to look bad 10 months of the year.

• Roses are best planted in the yard of someone else.

• Daylilies do not ever look good as a border plant.

• Make drainage a top priority when planting conifers.

• Educate yourself about rootstocks suitable for your zone before you buy grafted conifers.

• Thoroughly check and try to fix the roots on every conifer that you plant.

I could probably list another dozen things that I’ve learned and that I could write a book about for each point above, but, after the heat and lack of rain at my house this summer, I’ve got to make some changes.

The conifers, Acer palmatum ‘Orangeola’ (Orangeola lace-leaf Japanese maple) and Picea glauca var. albertiana ‘Gold Tip’ (gold-tipped Alberta spruce) in the front yard of Bill and Tracy Blevins' garden in Spotsylvania, PA

Watering Conifer and Evergreen Trees

I spend 75% of the time in my garden holding a hose. Due to the soil type and the layout of the beds, an irrigation system is not an option. It takes at least six hours to water my part of the yard with a hose.

This year, I’ve had to water my plants at least once a week. I water some areas in my garden two or three times per week.

Here is a shortlist of things I’ve learned while watering:

• Watering every other day lets me see every plant frequently. I’m not expert enough yet to be able to solve the problems I find, but I can spot them early. I’ve mastered finding sawfly eggs and I was successful at getting ahead of them this year before they ate my conifers.

• Another good thing about spending so much time with each plant is that I can make minor pruning cuts regularly, rather than being surprised and needing to make a major cut.

• That’s about it for the benefits. Navigating three carts with a couple hundred feet of hoses through trees and around beds, while constantly disconnecting and reconnecting them, is a real pain.

• Newly planted conifers initially require more water and, as a result, I’ve started planting annuals near them to remind me to keep them watered.

• Once established, conifers do not require a lot of water.

Spacing Out Conifers and Evergreens

I mentioned that I initially followed the suggested spacing that is printed on my plant labels. I quickly learned that those are normally wrong for my yard. Consequently, I started to spread out my conifers when planting, which led to another problem.

I suddenly had more space between my conifers to plant something else and, so, I did. Those unusual and interesting filler plants are what I’m constantly watering, and they also require the most hands-on maintenance!

I’ve figured out that it is not conifers that require work. It’s all of the other plants!

Planting Between Conifer and Evergreen Trees

After six years, I’ve started relocating plants to make being out in the yard more enjoyable. Conifers are being spaced out appropriate to their real, eventual, and mature size. I’m starting to accumulate pollinator plants in one place.

Milkweed for the Monarch butterflies grows where I can easily mow around the bed. Lower-maintenance, ornamental grasses and bulbs are filling in the new, empty spaces between the conifers.

Hopefully, after another five years, I’ll be spending a couple of hours every other day enjoying my plants, while holding a glass of wine, rather than the end of a hose.

Or, maybe it will just rain.

Favorite Conifers

• Metasequoia glyptostroboides ‘Gold Rush’ (Gold Rush dawn redwood)

• Chamaecyparis pisifera ‘Curly Tops’ (Curly Tops sawara cypress)

• Pinus mugo ‘Dolly’s Choice’ (Dolly’s Choice mugo pine)

• Abies balsamea ‘Weeping Larry’ (Weeping Larry balsam fir)

• Cryptomeria japonica ‘Radicans’ (Radicans Japanese cedar)

Conifers I Can’t Grow

• Larix spp. (larch)

• Abies koreana (Korean fir)

• Pinus strobus (eastern white pine) cultivars

• Chamaecyparis obtusa (Hinoki cypress)

• Tsuga spp. (hemlock)

Plants I will Never Grow Again

• Passiflora incarnata (purple passionflower)

• Pole beans

• Roses

• Iris

• Conifers from seed

Fun, But Not Conifers

• Aralia spinosa (devil’s walking stick)

• Aralia cordata ‘Sun King’ (Sun King Japanese spikenard)

• Tulipa sylvestris (wild tulip)

• Athyrium felix-femina ‘Godzilla’ (Godzilla lady fern)

• Oenothera glazioviana ‘Tina James’ (Tina James red-sepal evening primrose)

Photographs by Bill Blevins.

By Jack Christiansen
April 13, 2020

Read about planting and caring for a favorite ornamental conifer: the cedar.

Cedar galore: a panorama of the Christiansen Garden in San Jose, CA

When I first started my garden 10 years ago, I did not have a clue as to what kind of plants I would use to fill it. My son and I installed tons of rock for the hardscape, but I didn’t have a clear idea of how or what I wanted to plant. It was when I attended a bonsai show in San Jose, CA, and met a vendor there who used Cedrus (cedar) for his bonsai that I was hooked.

The conifer, Hillier’s HB Atlas cedar (Cedrus atlantica ‘Hillier’s HB’)

Starting a Cedar Conifer Collection

Conifers were seldom seen at local nurseries in the San Jose area at the time, and, what was offered was not that inspiring. The vendor at the bonsai show displayed a particular cultivar, Cedrus libani ‘Green Prince’. That plant, like no other on display, made my heart skip a beat. Even now, many years later, ‘Green Prince’ still mesmerizes me.

I enjoy many species of conifers, but none more than Cedrus. Everywhere I look in my garden, there is a cedar.

My go-to handbook for finding cedars back then was the catalog Larry Stanley had published for 2007-2008. I spent a lot of time reading it from cover to cover. Although all of the conifers listed interested me, I opted to buy as many dwarf cedars as I could. Yes, the Addicted Conifer Syndrome set in, and there was no turning back!

The conifer, a prostrate Himalayan cedar (Cedrus deodara ‘Prostrata’)

Seeking Rare Cedars

I was determined to search out places in Oregon and Washington that listed hard-to-find cedars. I mused about what those unique plants would look like in my rock garden. I asked myself if they would grow, and what kind of shape they would take over the years?

I have 23 cedars in my garden now. I also appreciate the large ones that were planted in my community decades ago. Cedars have always been my favorite trees in the landscape, but I never knew the names of the trees or the number of varieties.

I hope you enjoy the pictures of some of the different cultivars growing in my garden.

The conifers, Feelin’ Blue Himalayan cedar (Cedrus deodara ‘Feelin’ Blue’) and Horstmann Atlas cedar (Cedrus atlantica ‘Horstmann’)

Tips for Planting and Growing Cedars

My experience choosing and growing cedars taught me the following:

• Only purchase a plant that can grow in your USDA zone. Cedars will not fare well with long periods of hard freezes or humid summers. Some varieties are more cold-hardy than others. Check the zone where you live and compare the recommendations of the grower for best results.

• Make sure that the plant you purchase is compatible with the size of the space you have in mind for it. With good pruning skills, you can generally make it fit. Cedars come in various sizes, from miniatures to full-sized trees. Check the 10-year size estimation tag for the best placement.

The conifers, golden Atlas cedar (Cedrus atlantica ‘Aurea’) and Deep Cove Himalayan cedar (Cedrus deodara ‘Deep Cove’)

• Cedars prefer a soil that drains well. Here in Northern California many of us have heavy clay. Planting on mounds or slopes helps with drainage and keeps the plants happy.

• Cedars do not like to be drenched by heavy watering. Once established, cedars are very drought-tolerant. New plantings need to be watered regularly for at least the first couple of years.

• I have found that cedars are quite free of insect damage. Newly planted trees watered from overhead can develop fungus during the heat of summer. Spraying the cedars against fungus will ensure healthy and happy plants over time.

The conifer, a blue weeping Atlas cedar (Cedrus atlantica ‘Glauca Pendula’)

• In my experience, the best time to transplant cedars from containers into the garden is when they have finished their first spring growth, and after that growth has hardened off. Your own zone and climate may dictate different timing.

• Unless you want your plant to grow as a ground cover, many cedars will need staking to get them up off the ground and to encourage them to grow upward. I have allowed some plants to grow naturally and have trained others to be more vertical. It is up to you. Just be mindful of the size parameters of the plant and where you place it.

• Do not be overly concerned if your newly planted cedar does not take off immediately after planting. Cedars need time to establish a good root system. Position the young plant where it gets sun, but not hot wind and extreme heat. Newly planted trees usually start growing sometime in the third year.

I wish you well enjoying cedars!

Photographs by Jack Christiansen.

By Colby Feller
November 3, 2019

Make the most of limited spaces with rooftop conifer gardens.

The rooftop Conifer Corner garden in 2015

Like any great pugilistic match, the first few rounds are a feeling out process. You have to learn the strengths and weaknesses of your opponent and, adapt and be prepared for surprises. Like a boxing match, the conifer test and display garden atop the Arsenal in New York City, which was my first experience with conifers on rooftops, took a few rounds to feel out, but now it is, I believe, a knockout.

In the fall of 2010, a small conifer test and display garden was installed atop the Arsenal in Central Park. Located on the East Side at Fifth Avenue and 64th Street, the building currently houses the offices of the headquarters of New York City’s Department of Parks and Recreation and the Central Park Zoo.

The garden has a north-facing exposure, the building protecting it on one side, but the garden is still fairly exposed. The Arsenal rooftop is a challenging location as the garden is neither surrounded by buildings nor under a tree canopy, and is subject to very high winds.

Conifer Plant Preparation for a Rooftop Garden

The plants must also be well-chosen, as there is no irrigation system or formal maintenance program. Instead, the garden is cared for with the help of interns and volunteers (more information about, and pictures of, the original installation can be found in the Winter 2011 CQ, as well as in an article by Sean Callahan, “Hidden Gem in the Making” on the ACS website).

This garden, called the “Conifer Corner”, has now survived its eighth winter and seventh growing season. During round one, we had a 75% survival rate. A couple of factors are likely to have been responsible for the lost plants.

Although I am a proponent of fall planting, logistics forced the initial planting into the first week in November, which may have been a bit late, and this was followed by one of the worst winters on record. Perhaps, if the plants had been more established, fewer plants would have been “knocked out”. The good news is that during the later rounds, with winter’s delivering record cold and snow, only five plants were lost from the remaining original installation and these were specimens which were replaced in year one.

Another view of the Conifer Corner garden atop the Arsenal in 2015

Challenges of a Rooftop Conifer Garden

The plants definitely illustrated an “all or nothing” pattern at the site. Besides those plants which had to be removed, only a couple of the remaining specimens looked a bit worse for wear after the challenging first winter, but most looked perfect and were pushing new growth.

I have noticed a trend with conifers here in Manhattan; year one appears to be THE year which makes all the difference. Even in less severe conditions, with proper irrigation, year one poses a challenge, and the plants are either lush and vibrant or completely dead, and then the remaining plants are off to the races.

Perhaps not surprisingly, early expectations as to which plants would do well, did not play out. From the beginning, we recognized the site as being tough—no irrigation, a light-weight soil medium with little organic matter (Gaia soil), high winds, an urban environment with resultant pollutants, and the urban heat island effect.

We thought plants like Pinus heldrechii ‘Irish Bell’ and the various junipers would be as tough as nails, and the Cedrus more delicate, but we were incorrect. One might be inclined, since this was in a single test garden with limited specimens, to call this a fluke, but at another site in Manhattan I work on, which features a number of conifers, P. heldrechii and any number of junipers also did not survive.

It may be that these plants have difficulty in the City because they are grown in container gardens. However, interestingly, my father also had some difficulty with the Juniperus horizontalis ‘Ice Blue’ in the ground on Long Island, as it appears fussy until well established. Only one of two Juniperus horizontalis ‘Monber’ Ice Blue™ planted at the Arsenal survives, again illustrating the importance of care until the plants are acclimated and established.

Dwarf and Miniature Conifers in Rooftop Gardens

Although in general dwarf and miniature varieties of plants seem to be more robust; on urban rooftops, the larger juniper specimens have done well, while our dwarf favorites seem to be hit or miss. Plants like Juniperus procumbens ‘Nana’, J. squamata ‘Blue Star’, as well as the ‘Ice Blue’ mentioned above have turned out to be not well suited to rooftop environments.

Junipers in general, though, may not be the right choice for rooftops for completely different reasons. On the terraces and balconies in the City, clients live in close proximity to their plants. Working with junipers and installing them can give us gardeners the “juniper itch”, and although clients may not be as entangled with the plants as we gardeners, the people who own these gardens may like to brush their hands along plants, walk barefoot outdoors, and may be allergic.

The rooftop Conifer Corner garden's progress from 2014

Rooftop Conifer Gardens and Summer Desiccation

In the City, wind and the resulting desiccation are also factors to contend with. Many times we think of this as a winter phenomenon, and is especially a concern in containers which freeze solid during the winter, the frozen soil adding to winter desiccation.

Interestingly, this has not been the case for conifers here in the City, either for the dwarf plants discussed here, or larger specimens which can be used as hedging material—Juniperus chinensis ‘Hetzii Columnaris’, Juniperus virginiana ‘Emerald Sentinel’’, and various Thuja, for example. Even with proper irrigation, it appears desiccation is a summer event in the City, and when compounded with the hot buildings and HVAC venting atop many of these roofs and terraces, there is no room for error. The lack of irrigation at the Arsenal makes it a true test garden in the summer months.

Anomalies and Aberrations

Although I will not list every plant at the Arsenal, a number of Chamaecyparis which were pre-existing at the site, as well as the Chamaecyparis obtusa ‘Nana Lutea’ and ‘Lynn’s Golden’, which were planted in the Fall of 2011, have done very well. Then there is an odd trend where the fairly globose, or somewhat pyramidal forms have not retained their shape, but have grown horizontally and irregularly, even though neither lack of sunlight nor crowding are issues at the site.

Two Cedrus: C. deodara ‘Prostrate Beauty’ and C. deodora ‘Blue Ball’ both did well for five years, and then after pushing Spring growth, both completely defoliated in a matter of a week. Being that they survived for so long, and have performed admirably at this site and others, I will call this an aberration. We are trying two more Cedrus at the site which seem to be very content. Cedrus fall into the surprise category, as we thought they would be more delicate, and I had never seen them used on rooftops before.

The rooftop Conifer Corner garden in 2013

Thriving Cultivars at the Conifer Rooftop Garden

The other conifers introduced into the garden were a very small Picea abies ‘Gem’ (since deceased), Abies balsamea ‘Piccolo’, and Tsuga canadensis ‘Minuta’. Since these are single plants, any observations are of limited value; but I was surprised by the success of the fir, considering the lack of irrigation and the humid weather.

I am pleased to see Tsuga surviving, as it may also be a good choice for shadier sites, and as we are expanding the garden this year into a new corner where shade plays more of a role. These are in addition to Cryptomeria japonica ‘Tansu’—which has excelled.

Caution to those who wish to use Cryptomeria on rooftops, they need to be protected. The specimen on the Arsenal rooftop sits low to the ground, and it is nestled against the building, yet it also needs a good number of hours of sunlight to thrive and remain full, thus making siting difficult. Various dwarf Picea abies cultivars have shown mixed results for us.

Adding Non-Conifer Complements

Any number of pine species and cultivars seem to excel on rooftops, including, but not limited to Pinus thunbergiana ‘Thunderhead’, P. densiflora ‘Low Glow’, P. sylvestris ‘Hillside Creeper’, P. banksiana ‘Schoodic’, and P. mugo var. mughus. Interestingly enough, pines appear to take sun and drought better than many of the other conifers, but suffer the most from winter desiccation, unlike the other conifers where summer desiccation is more of a threat.

We have also added some non-conifer specimens, but with a focus on dwarf plants such as Ilex crenata ‘Dwarf Pagoda’, Rhododendron keiskei x ‘Fairy’s Fairy’, and Acer palmatum ‘Winter Flame’. These plants add different textures and further blend the Conifer Corner with the rest of the garden. As an aside, Japanese maples do remarkably well on rooftops and are a lot less delicate than they may at first appear—I would dare say they are our best performing specimen container trees in the City.

Overall, at the test garden at the Arsenal, and other sites in the City, dwarf conifers do very well in containers due to their size, slow growth rate, evergreen foliage, and diversity of form, texture, and color. I find that conifers can make for a very clean, almost sterile and regimented design; so, for many people, one needs a fairly dense planting and inter-planting with non-conifer species to create a visually pleasing garden.

This is because unlike in a suburban garden, where your plantings are surrounded by lawn, trees, or beds, in the City, plants are in containers, and surrounded by walls, railings, pergolas, and the building itself—already have very “constructed” environments.

The Conifer Corner garden on top of the Arsenal in 2013

Addressing Limited Spaces with Rooftop Gardens

In just the few years, the scale of the Arsenal test garden is already feeling mature, with plants beginning to “kiss”. As always, the challenge is to find a balance, because on the rooftop, like many rooftops in the City, there is simply limited space into which to transplant the existing specimens, or to add more plantings and containers. Perhaps this is why annuals and tropicals are so popular on rooftops; you start with a blank canvas year after year. And, yet conifers, which are underutilized on urban rooftops, and are too often relegated to hedging material, are in many ways ideal for these spaces.

Many people want the feeling of being surrounded by trees on their rooftops, and often large mature trees are not possible. But, much like bonsai, conifers can offer the shape, feeling, and structure of a large tree without being all that large. Not only are small specimen conifers ideal for small containers, but even large specimens, 6–12 feet, do very well in small containers. We have plenty of 6 foot plants in 18 or 24-inch containers which, although not necessarily ideal, do well and meet the challenge we face in the City with limited space. Acer aside, I can’t say that I have seen other genera of trees or large shrubs do as well in small containers.

Maybe there is no knockout plant, but at the end of the day Chamecyapris cultivars are my rooftop favorite, and do very well. They offer so many different sizes, colors, and offer a very unique “texture”, especially for those who find conifers too “rigid” or formal.

Gardening in the Sky with Rooftop Gardens

The Arsenal, as a conifer display garden display, illustrates well the various shapes, textures and colors available which work well on an urban rooftop. Another example, shown in photos here, of the possible uses of conifers in the City, is a garden I work on professionally. This garden, one of the highest residential garden spaces in New York City, is also composed mostly of conifers and has helped inform some of my own observations in this article.

That far up in the sky is like planting on the side of a mountain, and when you are not in the clouds, you have views of Central Park, the Hudson River and New Jersey to the West, and the East River and Queens to the East. This site only receives maintenance a few times a year, and, indeed, conifers are one of the few genera of plants which can face the challenges of the site while also adding four season interest for the owners of the apartment which has floor to ceiling windows all around.

The Arsenal garden has been well received. The ACS supported me in this endeavor as I stepped into the world of horticulture as both a hobbyist and a professional, and little did I know how this little garden would bloom both literally and figuratively.

If you are planning to visit the Big Apple and will be on the Upper East Side, call Kaitilin Griffin (during visiting hours, Monday-Friday, 9am-5pm, 830 Fifth Avenue @ E. 64th St.), (212) 360-8240, or e-mail her, kaitilin.griffin@parks.nyc.gov, prior to arrange a visit.

Photographs by Bruce Feller.

• We will list them on our website and link to them if they have an online presence.

• We will feature them in social media.

• We will remind members of the program every year in the spring CQ and direct members to the website for a current list of nurseries

• Give ACS members who identify themselves as such 10% discounts (retailers) or allow them to shop (wholesalers).

•  Display ACS brochures at POS (retailers).

•  Promote the ACS mission of educating the public about conifers

• Each nursery must have an ACS contact person.

• The ACS contact will provide the nursery with brochures/holder

• The ACS contact will also help the Program Manager with any updated information or questions from the nursery.

• The ACS will help the partner nurseries (as requested) with information about conifers, their nomenclature and their culture

• Country with most pine species: Mexico

• Conifer most common in the Southern Hemisphere: Podocarpus

• Conifer with widest circumference: Taxodium mucronatum (T. distichum var. mexicanum) – El Árbol del Tule, Mexico

• Only pine occurring in the Southern Hemisphere: Pinus merkusii in Sumatra
  

• 60/40 shade cloth, which is sold by many nurseries and online. It is generally 4’ wide and sold by the foot. Buy what you think you’ll need to cover your plant. I bought enough to make two 8’ x 3’ panels.

• ½” EMT (electrical metallic tubing) – the conduit used by electricians to run wiring. I used three 10’ lengths as I made a two-part screen. (If you want to make a three-part screen, get four lengths.)

• ¾” EMT – three one-foot lengths for sleeves to support the ½” conduit. Flatten on one end to make them easy to drive into the ground.

• Hex head screws and cable ties

• Battery pack drill

• Hex head driver

• Hammer to fl atten end of ¾” conduit

• Center Punch

Photograph by Rowe Arboretum

Although not realized at the time, the development of new cultivars of arborvitae, the hobby of one of the authors, took a giant step forward when it was noted in Chub Harper’s yard that a Thuja occidentalis ‘Filiformis’ was producing seed. For 20 years, the senior author had been planting seeds from Thuja occidentalis cultivars (23 different ones) in an effort to develop something new.

The effort met with success on three occasions, an average of one new cultivar every seven years. Perhaps because Chub realized that new cultivars come more readily from witch’s broom seed (one of Chub’s well known specialties) than from Thuja seed, he gave me carte blanche to pick all I wanted. The yield was not very interesting; half the seedlings had ‘Filiformis’ foliage and half normal foliage.

For a reason which is now not clear, all were discarded or given away except for one with normal foliage which was planted in the yard. It grew into the large non-descript plant shown and out of curiosity some of its seeds were planted.

This “generic” Thuja occidentalis was grown from a seed from ‘Filiformis’. It is unique in that its seeds produced a wide variety of Thuja occidentalis cultivars

Variable Cultivars from Parent Thuja occidentalis
The result was surprising. The seedlings were a bonanza of unique plants, some with foliage which was most typical of Thuja and others with the threadlike foliage of ‘Filiformis’. Of those with foliage resembling Thuja, some were globular, others columnar and a few pyramidal. The amazing part was that they were all progeny of a single, ordinary looking arborvitae.

The uniqueness of such an event is brought home by Humphrey Welch’s statement in his Manual of Dwarf Conifers to the effect that the probability of raising a new dwarf from a packet of conifer seeds is in the order of millions to one against.

To the contrary, we had many from a few seeds. Their variability is too great to be described in a few pages. Thus, we have limited the presentation to only a few, particularly those which are older and more mature.

One of several stands of Thuja occidentalis ‘Filiformis’

Cultivars with ‘Filiformis’ or ‘Filiformis’-like Foliage
Three plants are described as noted above, all came from seed from the mundane tree. Thuja occidentalis ‘Pincushion’ is characterized by whip-like foliage so abundant that it is not possible to see the approximately one inch long trunk. Some of the foliage strands have a very short branch at the end.

It is green in color, but interspersed are a few brown filaments making its name appropirate; the less abundant brown filaments can be considered pins stuck in the abundant green foliage, visualized as the cushion.

The original plant, now seven years old, is 27 inches across and 32 inches tall. Rooted cuttings also have foliage making the trunk invisible. A number of young seedlings have foliage similar to ‘Pincushion’, but differ in that they have easily visible 4- or 5-inch trunks.

Thuja occidentalis ‘Pincushion’. Original plant. The trunk is extremely short

‘Pincushion’, 'Little Filley', and ‘Fuzz Ball’ Conifer Cultivars
The foliage on Thuja occidentalis 'Little Filley' is unique compared to that on ‘Pincushion’. Only an occasional thread-like strand may be seen. Instead, there are many branches coming off at multiple angles, making the plant very irregular.

The branches and branchlets are all of approximately the same diameter and, since they seem to be the only structures containing chlorophyll, one might expect that the growth of the plant would be slow. So far, at age eight years, it is 15 inches tall and 10 inches wide.

Another unique plant is Thuja occidentalis ‘Fuzz Ball’. From a 4-inch single trunk arise several branches (not visible in the photo) which ascend in close apposition for a short distance and then end in threads of ‘Filiformis’ foliage. The foliage is abundant, largely unbranched, and merges to form a very symmetrical single ball.

If the ball should become very large, it could be a valuable accent plant. Its ultimate size can, of course, not be predicted. The plant pictured is 4 years old and 12 inches tall. One cannot judge the chlorophyll content of this plant from the picture since it was taken in the winter when all plants in this category have foliage which is brown and in some cases almost black. The variability of these plants starts when they are about two years old as demonstrated by the two of this age

Thuja occidentalis ‘Little Filley’. Original plant is 7 years old

Cultivars with Foliage More or Less Typical of Thuja
Although the plants with foliage closely resembling typical Thuja were, with some exceptions, not as unique and attractive as those in the other group, they nevertheless came in a number of shapes and sizes. Some were columnar, some globular and some roughly pyramidal.

The foliage on many of these was loose and, in the overall, they were not of the quality of many well-known Thuja. As a consequence, they have not been named or propagated. An example of loose and open structure is seen in the three very similar, roughly pyramidal plants. They seem disinclined to grow tall and might be suitable as a low hedge.

The typical Thuja foliage of two in this group was gold in color and not unlike that of other yellow cultivars. One of these had an occasional ‘Filiformis’ branch. Their poor structure made them inferior to other yellows and, thus, they have not been named or propagated.

Thuja occidentalis ‘Fuzz Ball’. Original plant of an unusual dwarf

Plants which were virtually identical, but coming from different seed, as was the case with the plants illustrated above, were not unusual. The form which was most often replicated was globular or slightly oval and had finely-cut foliage which vaguely resemble that of Thuja because the foliage was of limited length.

The outline of the plant was more smooth than that of the usual globular plant. Because of these characteristics, the first plant was named Thuja occidentalis 'De Luxe'. The numerous subsequent forms had for added interest typical broad Thuja foliage embedded in the finely-cut foliage. These plants still had a smooth outline and from a distance appeared the same as others. They have not been specifically named. As with many globes, these plants when old and large tend to fall apart with a snow
load.

We are attempting to determine whether any of the many seedlings of this type will be resistant to this kind of damage. So far, those which opened up in the winter closed in the spring. As above we have in a rather cavalier fashion separated these plants into two groups based on their foliage, occasional plants such as that here show characteristics of both groups making them impossible to classify.

Two year old seedlings showing variability at an early age

Practical Considerations with Conifer Cultivars
A disadvantage of attempting to duplicate this method of developing new cultivars is the time involved. Thuja occidentalis ‘Filiformis’ rarely produces seeds. Of two approaching 25 years of age, with which the authors are acquainted, one has produced seed once. Once the seed is procured, there is another long wait for the seedlings to produce seed.

This stage might be hastened by the use of plant growth regulators or by girdling or otherwise injuring the tree. Once the seedling (which would be of the generation of the plant) has itself produced seed, there is another wait before the nature of the final product can be determined. This is, of course, when the fun begins.

An unusual columnar plant of this progeny. The foliage is open and loose

Cultivars: A Result of Genetic Chaos in Conifers?
The variability of these plants appears to be the result of some genetic chaos occurring at the time of pollination. This deviation from normal events appears to affect not only the morphology of the plant arising from the embryo, but also the metabolic processes involved in germination and embryonic growth. The latter disruption is probably responsible for a germination rate for these seeds rarely exceeding 30%, a rate much less than that for most cultivars

Of great practical interest about plants from this progeny is that they seem resistant to burning of the foliage by the sun. Whereas we experienced days, in which the temperature hovered about 100 degrees F and Thuja of other progeny were either partially or completely burned, full sun did not cause burning on plants from this progeny, whether the foliage could be classed as Thuja-like or ‘Filiformis’.

For those who may be interested in seeing more of the variability of arborvitae grown from the seed of this plant, 34 different, relatively mature plants are on exhibit at the Stanley M. Rowe Arboretum, 4600 Muchmore Road, Cincinnati, Ohio 45243.

These open and loose pyramidal plants came from di!erent seeds from the generic Thuja occidentalis above

Text and photographs by Clark D. West and Christopher Daeger.

The longleaf pine, Pinus palustris, once dominated the landscape from Virginia to east Texas, covering an estimated area of over 90 million acres. With the arrival of the British explorers in 1607 and their subsequent exploitation and destruction of the longleaf pine forests, this tree virtually disappeared in many areas. In cultivation, Pinus palustris has no registered cultivars and is, therefore, seldom grown by ACS members. However, the tree has many desirable attributes, particularly in the “grass stage”. The species features 8” to 20” needles, with 6” to 10” cones. The tree itself grows to a height of 130’. Longleaf pine is an imperiled species, and the American Conifer Society has made its first contribution toward the re-establishment of this historic and important conifer.

When John Smith and other British explorers arrived in 1607, they were searching for gold and silver in Virginia. They did not find gold, but they did find another valuable resource, the longleaf pine. From the longleaf pine came naval store products such as pitch, tar and turpentine which were then sent to England. Since England was quickly becoming the dominant naval power of that era, and naval stores were vital to maintaining wooden ships, these products were critically important to their growing fleet.

Soon the naval store industry was exerting a huge toll on the longleaf pine forests through destructive pine resin harvest. This timber was also highly prized in the booming ship building industry and for construction by the colonists pouring into the American Southeast. The forests were eliminated so that agricultural crops could be planted to support the growing human population. Forest regeneration was stifled by the presence of feral hogs which fed on the roots of the longleaf seedlings. Next, the trees were subject to widespread harvest during the era of steam train logging, as the longleaf pine has exceptional straightness and strength in its timber. Lastly, fire was suppressed, which is a critical component of the longleaf pines growth and development.

In Virginia alone, it’s estimated that by 1850 more than one million acres of longleaf pine forest had disappeared. Today, scientists have counted fewer than 2000 native Pinus palustris remaining in the natural forests of Virginia. Pinus palustris has been almost eliminated from its northern most range in the USA.

Longleaf pine forests are an important component of the ecology of the American Southeast. Longleaf pine is a keystone species and mediates fire effects which provide habitat for a wide variety of plant and animal species including Bobwhite quail, red-cockaded woodpeckers, and Bachman’s sparrows. Since the forests often contain wet seepage bogs and flatwoods, Mabee’s salamanders, pitcher plants and sundews can be found. Species of orchids, lilies, wildflowers and sedges also proliferate. Longleaf pine can live for more than 300 years. As a result, they may be most helpful for long-term carbon sequestration. The utilization of carbon is not only good for the Southeast, but our entire planet.

There are many efforts directed toward the restoration of the Pinus palustris. The federal government, numerous environmental groups and even private landowners have partnered to replant the longleaf pine. One such effort is located at the northern range of longleaf pine in Sussex County, Virginia at the 232 acre Joseph Pines Preserve (JPP). Inside the Joseph Pines Preserve, over 60 acres of land have been restored with over 10,000 native Virginia, longleaf pine trees. The seed was collected from the last native longleaf pine trees in Virginia by biologists from Meadowview Biological Research Station and the seedlings were raised at their nursery in Woodford, Virginia. In addition, the goal of Joseph Pines Preserve is to restore the biodiversity of the indigenous longleaf pine – pitcher plant ecosystem (see prospectus on the Joseph Pines link at www.pitcherplant.org).. The preserve is also dedicated to capturing the entire Virginia longleaf pine (Pinus palustris) genome by grafting, fascicle rooting, or seed propagation. Joseph Pines Preserve has recently purchased an adjoining property to create The Center for Biodiversity. This facility will serve as an education and training center for longleaf pine/pitcher plant ecosystem restoration and a nursery will support conservation and restoration efforts.

At the 2014 ACS Board of Director’s Meeting in Atlanta, the Board approved a donation of $1,000 to Joseph Pine Preserve from the ACS Endowment Fund. These funds will assist JPP’s efforts to propagate, replant and preserve the native Virginia longleaf pine. This donation marks the first time the ACS has actively supported an effort to conserve conifers in the wild. Thank you to the Board as the ACS fulfills another important aspect of its mission.

I am working with Dr. Phil Sheridan of Meadowview Biological Research Station to offer another opportunity for the ACS members to personally assist with the restoration of the Virginia longleaf pine at Joseph Pines Preserve. This spring, JPP will be planting another 1,000 Pinus palustris, and you can help to plant these young trees. It is impossible to predict when the ground will be suitable for planting. Therefore, look for updates on the ACS website starting any day. Interested ACS members can also contact me directly by email at lnau@frontiernet.net or cell 585-202-1815. We hope to not only plant these 1,000 trees, but also have some time to learn about this unique and fragile ecosystem. Join us in restoring the Virginia longleaf pine to its northernmost habitat.

http://youtu.be/LZGJJzdRHHA

By Web Editor
March 8, 2021

Fairy garden in a wagon.

Text Elden Wheaton
Photography Ron Elardo

With little fanfare, a new form of gardening has been rapidly gaining ground. Extensive displays of miniature figurines, furniture, and tiny plants, all sold at nurseries, are the telltale elements found in what are known as fairy gardens. They are popping up mostly as indoor gardens and containers, set outside during warm weather in garden beds, or simply maintained in homes and on porches. They meet the need for wanting a garden without having the space or time for a large one. Then there’s the whole cuteness of creating and playing in your own tiny, secret garden, decorated with things like furnishings and accouterments of dollhouses.

At our local nursery in Adrian, MI, the phenomenon has added new kinds of plants, too, many of which are conifers. I have been creating small garden bowls with little conifer forests in them for quite some time. Lately, little conifers have started catching on at our fairy garden classes. Enthusiasts have added conifers among their tchotchkes, /choch-kees/ (Yiddish for a small object, a trinket). The result is a personal expression of one’s imagination, like a bridge to a castle nestled in the woods, or a witch’s hut secluded in the shadow of trees, waiting for Hänsel and Gretel.

The tchotchkes represent anything you can think of; the sky’s the limit. Figurines include gnomes, fairies, animals, and seasonal characters like Santa Claus. A Halloween scene might include scary ghouls and goblins. You can find them all, either online or at your local nursery. Check out the Internet, too. You’ll be surprised what you’ll find when you Google “fairy gardens”. DYI fairy garden ideas will pop up. Stores selling tchotchkes are relatively easy to find. North of Adrian, in Brighton, MI, there is a Fairy Garden Super Store. Suppliers will ship supplies free with certain orders. Also, magazines run how-to articles on fairy gardens. It’s dizzying.

Editor’s Halloween fairy garden with Platycladus orientalis ‘Franky Boy’ (Franky Boy Chinese arborvitae)
and Chamaecyparis pisifera ‘Blue Moon’ (Blue Moon sawara false-cypress).

Fairy gardens are very easy to create and manage. So, let’s start with some basic elements:

• You will need a container, something colorful with an interesting shape, but not too deep, to house the garden.

• The soil medium needs to be the kind that holds moisture and allows for good drainage.

• For the planting medium, mix peat, sand, fine basic compost, topsoil in equal amounts, and a handful of horticultural-grade charcoal pieces for improved drainage and moisture retention.

• Save the medium mixture in an airtight container for future gardens.

Chamaecyparis obtusa ‘Fernspray Gold’ (Fernspray Gold Hinoki cypress) in a small fairy garden.

Now for the conifers.

Any small conifers will work. These will be “baby” conifers that, when planted in the garden, can reach mature heights of 35 feet or taller. One of your jobs with these conifers will be to keep them small. Over time, you will find that the little trees will look mature even though they are kept tiny. Trunks and branches will thicken and give your plants a look of being old. You may even find your trees resembling bonsai. There is ample online information on pruning and keeping miniature trees little, including the tools to do it. I prefer using spruces like Picea mariana ‘Blue Planet’ (Blue Planet black spruce), Picea glauca var. albertiana ‘Elf’ (Elf dwarf Alberta spruce), ‘Pixie’ (Pixie dwarf Alberta spruce), and ‘Pixie Dust’ (Pixie Dust Alberta spruce), but any conifer genera will do. Just start with small specimens, no more than six inches tall. Next, the plants have to be prepped for planting in a semi-shallow container of no more than 12 inches deep.

It’s best to clean the rootballs of their original planting soil. Snip the root tips just a little bit, so that they will be stimulated to grow and grip the new planting medium. That way the roots will begin to spread out and multiply. Gently dig a small place for each plant. Once installed, gently press down the soil around the conifer. Next, use a small cooking baster or eyedropper to water the plants. Like all containerized plants, your new garden should never be allowed to dry out, at least not during the growing seasons (spring, summer, and fall). Use a water probe to know when to water.

During the growing seasons, the fairy garden will need fertilizer. Osmocote 15-9-7 is the best formula. I mix a teaspoon full of fertilizer with water in a bowl for easy application. Just remember that less is better. Too many plant parents think they need to overfeed their babies. Also, pay attention to sun requirements that will depend on the numbers and kinds of plants you install. Most conifers like full sun. However, remember that plants in small containers need to be protected from the sun’s hot, direct rays. Some fairy garden practitioners place their miniature gardens here and there under trees and other plantings in the garden to create surprises.

In Winter, your fairy garden will require more moderate light and minimal watering. If the rootballs freeze, stop watering until spring comes, and the rootballs thaw. Garages with windows are good places to overwinter your conifer fairy garden(s). Attached, unheated garages rarely reach freezing temperatures. Three-season porches are good storage places, too. I say “gardens” because, once you do one, you will want to do more. At a recent fairy garden workshop, one participant created her 24th fairy garden to join all those already housed throughout her home! She was not alone in having a collection of fairy gardens. One definitely leads to several.

Assorted conifers and completed fairy gardens.

Other living elements can be added to complement the conifers. Natural moss can be the lawn. Varieties of small hostas, sedum, and other ground cover perennials can also simulate a lawn. Hillside effects are fun to create, in order to enhance further a three-dimensional landscape. Small-sized gravel and wood chips can duplicate pathways, while stones can mimic rocks and outcroppings, even mountains. Once you have decided on the physical landscape, it’s time to add things like wells, houses, fences, figurines, or whatever else you can find. Even ponds can be simulated with pieces of blue or green plastic.

Fairy gardens are not just for older gardeners. Parents and grandparents have shared the fun with children, who, in turn, exhibit a genuine love for tiny gardening. Children take to it easily and reveal their own flair for the fantastical. In Adrian, containerized conifer classes have been held for children at our city library, private homes, and nursery schools. Children regularly accompany family members to fairy garden classes at our nursery. They like building and tending their own gardens.

ACS members will be gratified to know that conifers have now become part of this activity. Who knows? Maybe the youngsters creating fairy gardens today might be planting full-sized conifers in their gardens tomorrow and might even be joining the American Conifer Society. Whatever the age, fairy gardens are showing up all over. They’re fun to create and they bring joy to their owners.

Elden Wheaton is nursery manager at Barrett’s Nursery and Landscaping in Adrian, MI. He is a certified landscape designer, educated at Michigan State University.

Getting started with your bonsai hobby is as easy as heading outdoors.

Pinus ponderosa (Ponderosa pine), styled as a semi-cascade bonsai for 12 years
by Carl Morimoto who purchased the plant at a regular nursery in California

The Conifer Bonsai Hunt Begins

Spring is here, and I cannot think of a better time to go on the hunt for plants, either to start as bonsai, or to add to an existing collection of bonsai. Nurseries have already begun receiving new inventory for the season. The warmth of the sun beckons us to get out of the house and to be the first in line to view the new stock. Spring can also send us in other directions, in order to investigate sources of future bonsai. You might be surprised to discover, just where new finds exist.

Juniperus californica (California juniper), styled as an informal upright bonsai for 17 years
by Seji Shiba who collected the plant in the Mojave Desert, California

Many of my friends have scored specimens by digging up small trees or shrubs. Some plants have been growing in their own backyards. Many times, future bonsai have come from jaunts through the woods. Neighbors in my community have decided to remove plants from their own gardens and have even been willing to dig plants for me. It is exciting to explore the possibilities!

Taxodium distichum (bald cypress), styled as a formal upright bonsai for 21 years by George Shoptaw who collected the plant in Louisiana

An older plant can have a special potential and may reveal interesting trunk shape and branching, well before bonsai-ing. On walks in my community, I have noticed plants I have wanted to acquire. I have gone so far as to ask politely if I might remove a plant in exchange for a new plant of the same size.

Bartering for plants and services rendered can result in a nice payoff. For example, old hedges of Taxus (yew) are a great source of bonsai. The plant hunter might have to go far afield to catch sight of a specimen which is worthy of transformation into a bonsai.

Callitris oblonga (Tasmanian cypress pine), styled as a literati bonsai for 10 years by John Thompson who purchased the plant at a bonsai nursery in California

Scouting for Conifer Location

Mountain areas and forests can yield great specimens. The San Francisco Bay Area, where I live, offers a wide diversity of regions, which are home to many species of conifers. Plants native to the Mediterranean climate grow here and add a new dimension for beginners and also experienced collectors. Always check your USDA zone to find what plants will thrive in your area!

When digging conifers in the wild, the land owner, be it a governmental unit or a private individual, generally requires permission to enter an area and remove plants. Conifers taken from the wild need special aftercare.

Mortality rates can be high. I would not recommend digging a plant, especially if there is no way to ensure a sufficient root ball. A quick Google search will provide sources on trunk caliper versus minimal root ball diameter.

Many of these naturally-occurring trees may live in small cracks or crevices. The weather in these conditions often creates an extreme environment, in which plants may only grow 1 inch or less each year. These plants make for highly desirable, collectible bonsai.

Juniperus chinensis ‘Shimpaku kishu’ (Chinese juniper), styled as a slanting bonsai for 12 years
by the Bonsai Society of San Francisco. The plant had been collected from a garden in California

Club members whom I know have developed their trees over years. They have shown their creations at yearly meetings. The bonsai are wonderful examples of natural art and are often hundreds of years old. It takes a high degree of skill to reveal that hidden beauty. A number of bonsai collectors in different parts of the United States go out and gather plants annually. They sell them, in turn, to other bonsai enthusiasts, or to well-known bonsai nurseries. You can Google “bonsai nurseries” to find the locations of such sources near you.

Other sources, of both developed and potential trees, are bonsai club meetings. Anyone can attend these gatherings. Clubs have annual fundraisers, where members bring in and offer specimens for sale at a good price, in order to raise money for the club. Plants may have already been crafted into bonsai, or may be sold in an undeveloped state. Check your local listings for times and places of club meetings.

Cedrus libani ‘Nana’ (dwarf cedar of Lebanon), styled as an informal upright bonsai for 5 years by Jack Christiansen who collected the plant from his garden in Jose Jose, California

Starting your Bonsai Hobby

Whether you decide to start out with a sapling from a nursery, a mature plant from the wild, one from a yard, or even a finished specimen, it is good to understand the time element involved in the development of a tree. It is a good idea to match your bonsai knowledge with the plant you choose to buy. Some developed bonsai can be expensive.

You can also read about bonsai online and in books at your local library or bookstore. With the help of bonsai clubs, workshops, and ancillary materials, any individual can acquire the knowledge to be successful with trees.

I recommend two sources for bonsai history, style, and care:

• Herb L. Gustafson, The Bonsai Workshop, Sterling Publishing Co. Inc., New York, New York, 1996.

• Amy Liang, The Living Art of Bonsai: Principles & Techniques of Cultivation & Propagation, Sterling Publishing Co. Inc., New York, New York, 1991.

Cedrus brevifolia ‘Treveron’ (Treveron Cypriot cedar), trained as a sapling and styled as a cascade bonsai for 5 years by Jack Christiansen who purchased the plant at a bonsai nursery in California

Bonsai never have a final stage in development and are always labors of love. It is not unusual for bonsai to be passed down from one generation to the next. There are bonsai which are hundreds of years old. Many are displayed on tour at botanical gardens, such as the Jardin Botanique in Montreal, Canada. The time spent tending your trees will be rewarding for the years ahead.

Juniperus chinensis ‘Shimpaku kishu’ (Chinese juniper), styled as an informal upright bonsai for 7 years by Jack Christiansen who collected the plant from a neighbor’s conifer garden in San Jose, California

It may become more and more difficult over time to get down on the ground and maintain a rock garden, but bonsai trees and pots can be moved for ease of styling and tending. When the weather outside is miserable and forbidding, bonsai can be brought inside and styled. However, when temperatures rise, it is fun to get outside and bonsai.

Photographs by Jack Christiansen.

Jack is an ACS member, an avid bonsai-enthusiast and bonsai-creator. His garden is an excellent example of creative design and the integration of bonsai into the garden. His knowledge and photographic skills are well-known and widely appreciated. He lives in San Jose, California. Over the years, Jack has been a valued contributor to the CQ.

By Michael Larkin
February 7, 2020

Discover how to make your own hypertufa (stone-like) containers for your conifers.

Miniature conifer and succulents in a hypertufa pot. Photo: plantman56.blogspot.com

After attending my first National ACS conference in Oregon several years ago, my idea of using single season annuals in containers changed. Container gardens typically include tall spindly plants surrounded by colorful annuals, planted in faded plastic containers. As the season comes to an end, the plants get sadly redirected to the compost bin, one season and gone.

The conference tour visited several beautiful display gardens where I saw hypertufa (stone-like) containers planted with small conifers and alpine perennials arranged to form miniature landscapes. I realized then that there was a new group of plants that I could use in my container gardens. It did not take too long for my Pennsylvania garden to include many conifer containers of all shapes and sizes.

After the conference my goal was to create containers just like the ones I had seen in Oregon. I purchased and made many different containers. I experimented with different plants, different soil mixes and then I worked on making my own containers. This is what I found to work best for me.

What is a Hypertufa Pot?

Hypertufa allows you to be creative, childlike, and artistic, while making your own container. Even mistakes can look good. Instructions on how to make hypertufa containers can be found on the internet and in many garden magazines. However the most complete source of information was in the book, Creating and Planting Garden Troughs by Joyce Fingerrut and Rex Murfitt.

There are many ways to make hypertufa. My formula starts with equal parts of Portland cement, peat moss, and perlite. Thoroughly mix the cement with water to form a damp, but not wet mixture. Add liquid cement color to the wet mix to make the container more decorative.

Apply the mix, about 1½” thick, to the inside (or outside) of a mold, usually a large plastic container. After a day, gently remove the slightly hardened hypertufa from the mold. Wire brush the pot to create a textured, stone-like finish. Place the container in a plastic bag to keep it moist, slowly allowing it to cure for a few weeks. As it cures, the container will become stronger. Once properly cured, these containers can remain weather resistant for many years.

A hypertufa container waiting for planting. Photo: plantman56.blogspot.com

Making a Planting Mix for a Hypertufa Pot

Building a house requires a good foundation. Making a good container garden requires great soil. Whether you are growing conifers in hypertufa containers or annuals in plastic pots, success begins with creating a healthy environment for root growth. The growing medium has to provide roots with sufficient oxygen and also allow gas exchange in the root zone.

Bagged potting soil is mostly peat moss and within a short time the peat moss breaks down and compacts. My conifers need to stay in the containers for a few years and, therefore, the soil mix needs to remain functional. While searching the internet for just the right soil mix, I discovered the Garden Web forum and read about Al’s Gritty Mix, one of two mixes created by Al Fassezke – or “tapla” as he is known on the forum. His mix of ingredients not only creates a well drained, highly aerated soil for containers, but also allows for air to move through the root system and by-product gasses to escape. The ideal growing environment!

Ingredients for a hypertufa mix

When you make your own containers you can control the size and number of drainage holes. My containers have at least one 2” drainage hole which is then covered with a piece of window screen. We have been taught to use a layer of gravel on the bottom of the container beneath the soil to improve container drainage – no longer true.

Instead of extra water draining immediately into the gravel, the water actually “perches” or gathers in the soil just above the gravel. This wet area has no air space, which is not an ideal environment for roots. Roots grow best in well aerated soil. So the addition of gravel only reduces the available space for roots to grow. More detailed information on “perched water table” can be found by doing a search on the internet.

Conifer Selection for a Hypertufa Pot

Unfortunately, the conifers used in the container will eventually outgrow their space, and using slower growing plants will keep your planting undisturbed for a few years. Conifers are classified as mini (grows less than 1” per yr.), or dwarf (grows 1-6” per yr), which helps when selecting the right plant for your container.

The next concern will be to pick a plant that will survive the winter in a container. Start by using a plant that is at least one zone colder than your zone. However, additional winter protection may still be needed. Here are just a few examples of conifers and perennials that I have been able to grow successfully year round in containers in my USDA Zone 6 garden: Chamaecyparis obtusa ‘Nana’, Zone 5, Juniperus communis ‘Gold Cone’, Zone 4, Picea glauca ‘Jean’s Dilly’, Zone 4.

There are hundreds of alpine perennials, for example, selections of Sedum, Zones 2,3,4 and Thymus, Zone 3, Sempervivum - Zones 3, 4, and occasionally I use non-hardy succulents like Echeveria, Zones 8, 9 – around 150 species – which I bring inside as it begins to get cold.

Conifer in a hypertufa pot. Photo: plantman56.blogspot.com

Designing the Landscape of a Hypertufa Pot

A conifer container can have a design, one conifer in one container, or you can create a mini landscape. Many nurseries now carry mini and dwarf conifers in 4” containers, making it easy to plant multiple conifers and several alpine perennials in one container. Design is a matter of personal taste. I place a tall accent plant, possibly a small juniper, off center in the container.

To create a natural looking scene, place a grouping of rocks inter-planted with several alpine perennials around the conifer, add a creeping Sedum or thyme to hang over and soften the edge. Mixing leaf textures will create visual interest. Once everything is planted cover the soil with a mulch of fine gravel.

Hypertufa Pot Maintenance and Fertilization

Conifer containers require a sunny location and minimal care once established. Newly planted containers will need to be watered a little more frequently until the roots get established. Since the recommended soil mix has no nutrients, fertilizer is required. Care should be given not to overfertilize. More is not better no matter what you grow. Excess fertilizer in soil makes it more difficult for plants to absorb water and nutrients. Only give plants what they need.

I have found good success with a fertilizer that has low NPK (nitrogen, phosphorus and potassium). I use a very weak solution of liquid fertilizer on a frequent basis. In nature, plants do better with regular access to low levels of nutrients, as opposed to sudden large infusions. I use a fertilizer like Dyna-Gro’s Foliage-Pro 9-3-6, or similar NPK in a 3:1:2 ratio. It has all the primary macronutrients, secondary macronutrients (Ca, Mg, S) and all the micronutrients. Its NPK formula is very close to the ratio most plants actually use. I also supplement with a little time-release fertilizer in case I forget to apply the liquid fertilizer.

A larger hypertufa container of conifers, succulents, and low-growing plants. Photo: plantman56.blogspot.com

Conifer Winter Care for Hypertufa Pots

Many conifer containers can be kept outside all year. However, plant survival will increase if you provide some extra protection. Roots are exposed to colder temps in containers than they are if growing in the ground. As I mentioned above, select plants that are at least one zone lower than yours.

As winter approaches, one option is to relocate the container to a microclimate near the foundation of your house. Avoid the south side because it might cause the plants to warm and freeze resulting in heaving. For colder climates dig a shallow hole and sink the container in the hole. Mulch the container. Another option would be to place the container in an unheated garage or shed. The plants do not need light during the dormant period. Bring the pot back out as the temperature outside begins to warm in the spring.

Container gardening with conifers is something that anyone can do, even if you only have a small patio or deck. You are limited only by your imagination and a sunny location.

Discover the immense diversity of conifers in Northern California's Klamath Mountains.

A conifer panorama: Allison Poklemba (far right), climbs to the highest point on the Bigfoot Trail at Packer’s Peak in the Trinity Alps Wilderness

In 2009, just after the school bell rang for the last time that year, and my 30 seventh grade students ran out the door for summer, I jumped into my car and headed to the Mendocino National Forest in Northern California to start the first-ever, official thru-hike of the Bigfoot Trail.

I am the first person to plan, map, and hike the Trail, which I created by connecting existing trails and Forest Service roads. I decided to name it after Bigfoot, also known as Sasquatch, the large and mysterious creature purported to inhabit the mountains in this part of the country.

A thru-hike is a hike on an established end-to-end, long-distance trail, with continuous footsteps, that is completed within one calendar year. Over the next 20 days and 360 miles, I walked, mostly alone, on my way across the Klamath Mountains to Crescent City, CA.

The Bigfoot Trail follows the Boundary Trail through the Red Buttes Wilderness along the California-Oregon border. Dr. Jeffrey Kane is seen here on the Boundary Trail

A Hike Amongst the Conifers of Klamath Mountains

I first cooked up the idea of this hike in 2007 with my friend, mentor, preeminent botanist, and conifer expert, John O. Sawyer. We envisioned it as a way to connect existing trails, roads, wilderness, and botanical wonders across the Klamath Mountains.

This project would combine hiking and natural history by defining a new thruhike in one of the most speciesrich, temperate, coniferous forests on Earth. North America holds two of the most species-rich, temperate forests in the world: those of Southern Appalachia and those of the Klamath Mountains.

What do these locations have in common? Glaciers and seas did not completely cover them during the Cenozoic Era, and the mountains were monadnocks, or islands above the plains, offering temperate refuges to plants and animals over time. Both locations have historically maintained a moderate climate.

Conifer Diversity in the Californian Klamath Mountains

These areas are beyond the southern terminus of the enormous continental ice sheets of the Pleistocene Epoch (commonly called the Ice Age). Some plants undoubtedly remained in these regions through historic climatic change, while other species repeatedly moved in as the climate cooled, and the glaciers pushed southward, or, then, species moved out and followed other glaciers northward.

These dynamic fluctuations have cradled plant diversity in these two unique regions. The current consequences of these historical patterns are that the Klamaths and the Southern Appalachians have grand floristic diversity, a concentration of endemic plants, and a fundamental importance to the forest floras of nearby regions.

Per unit area, the Klamath Mountains and the Southern Appalachian Mountains hold more plant taxa than any others in North America. Plant genera such as Cornus (dogwood), Asarum (wild ginger), and various conifers (Pinus, Abies, Thuja, Chamaecyparis) grow a continent apart, while providing a comparative glimpse of ancient floras.

The heart of the Marble Mountain Wilderness is Marble Mountain itself, sprinkled with the rare California-endemic foxtail pine (Pinus balfouriana)

A Conifer Botanical Museum in the Mountains
Complex interactions between biotic and abiotic factors have encouraged and nurtured biodiversity in the Klamath Mountains over millions of years. The region is a botanical museum, hiding relicts of epochs gone by, which are called paleoendemics, such as Brewer spruce (Picea breweriana).

The region is also a cradle, promoting the adaptive evolution of new species, which are called neoendemics, like Baker’s cypress (or Modoc cypress, Cupressus bakeri). Complex climates and soils nurture biodiversity. The area also has a central location and continuity with other mountain ranges along the Pacific Cordillera.

Across this landscape, a mosaic of habitats mix at a crossroads of five biotic regions—Cascade Range, Oregon Coast Range, Great Basin, Central Valley, and Sierra Nevada—each helping to define the Klamath Mountains.

Within the geologic boundaries defining these complex habitat mosaics of the Klamath Mountains, there are approximately 3,540 taxa (species, subspecies, and varieties) of vascular plants and up to 38 species of conifers, depending on how one delineates the region. In addition to plants, the region holds exceptional diversity in amphibians, mammals, and birds.

Michael Kauffmann surveys the final climb up the Bear Creek Trail into the Trinity Alps Wilderness