True Fir Propagation

Abies firma ‘Halgren’

Abies firma

There are five Abies (True fir) species native to Japan: A. homolepis, A. marisii, A. sachalinensis, A. veitchii, and A. firma, with A. firma having the largest distribution over the other Japanese species. It is called the “Momi fir,” a term that also refers to any of the five species. To American gardeners cursed to live in hot, humid environments, Abies firma is the preferred rootstock for all the Abies cultivars. We have also used Abies balsamea var. phanerolepis as rootstock because it is more winter hardy than A. firma; but in any case we keep track of all our specimens’ rootstocks for years after being grafted, as knowing certainly can matter.

Abies firma ‘Halgren’

This past winter’s grafting season all of our rootstock was Abies firma, but from two sources: 1) purchased 3-year seedlings in tree pots and 2) our own from our rooted-cutting program. We were stymied a bit in that the rootstock from both sources was a little thin, so we reduced our grafting menu to cultivars that could accommodate. Sometimes we used current-years’ shoots as scionwood, in other cases a branched two-year stem. For most Abies the graft takes are among the highest of all of our conifers, with any Abies species seemingly graft-compatible with any other. Cutting scions, preparing them, then finally grafting leaves the fingers gummy and dirty. Scion preparation is far more laborious than with the spruces and pines because extra caution is required to not scar the stems, and sometimes we’re forced to cut the needles individually with Japanese needle-nose snippers. In those cases it is actually twice as fast to graft the scion than it is to prepare it. All negativity leaves the grafter of the True firs, however, due to the deep aroma of Abies firma. Each of the firs has its own distinct odour, and it’s like a blindfolded wine taster who can probably identify the various samples. The American Abies grandis, for example, smells for all the world like tangerines, a delightful discovery for children that helps them to appreciate the uniqueness of trees.

Abies concolor ‘Archer’s Dwarf’

We grafted four cultivars of Abies concolor, a mountainous species commonly known as the “Colorado White fir,” although its range also extends into Oregon. The largest specimen grows in Yosemite National Park and is over 75 meters (246 ft) tall with a 4.6 m (15 ft) trunk diameter at breast height. Abies concolor was first collected by Augustus Fendler in New Mexico in 1846, then described by George Engelmann, and the specific epithet concolor means “all one color.” If I was the first botanist to describe it I don’t think that uniform feature would impress me enough to employ such a moniker, for the same could be said for other conifer species such as Abies procera or Picea pungens. The foliage of Abies concolor can vary greatly, at least in horticulture, where the needles range from a boring pale green to shiner-blue to golden – hardly just one color. Of course the cultivars with the most intense colors are preferred, and in the cold winter garden they are enhanced and strikingly noticeable. This year we grafted A.c. ‘Wintergold’, ‘Z-Mark’, ‘Blue Cloak’ and ‘Archer’s Dwarf’, and due to limited rootstock we passed on many other worthy candidates. ‘Archer’s Dwarf’ is becoming one of my favorites since it has blue needles a little more thin and delicate compared to the other blue forms. The specimens in our garden can grow into dense, flattened bushes or with a broad upright form. I suppose that the flatsos will eventually develop leaders too.

Abies concolor ‘Blue Cloak’

Abies concolor ‘Wintergold’

Abies concolor ‘Blue Cloak’ is aptly named for its slightly pendulous habit, and it was discovered about 30 years ago in a Christmas tree plantation in Washington state. Abies concolor ‘Wintergold’ can also grow low and flat, or with some assuming leaders. The color is as vibrant as it will get in mid-winter, and, the more sun the more the fun. Gardening with golden conifers is fraught with the urge to over-indulge, and for each vignette one tree is probably enough. You wouldn’t want, for example, to plant a ‘Wintergold’ near to Pinus contorta ‘Chief Joseph’, that would be too much fun. Abies concolor ‘Z-Mark’ is a flattened globe at the nursery, but then we harvest the short and stubby scions from the top. Its foliage ranges from steel-blue in winter, setting off its tiny, reddish-brown buds, to a mellow chartreuse color when the buds flush in spring.

Abies pinsapo ‘Horstmann’

Abies marocana

We have a couple of old specimens of Abies pinsapo ‘Horstmann’ in the landscape, and both are as wide as tall at about 25 years of age. When younger they could occasionally produce 18” shoots like they were attempting to revert and form an upright tree. They were happy but I didn’t have the space to accept their exuberance, so 90% of the wild growth was pruned away. They got the message, and have since avoided the urge to show off. ‘Horstmann’ was discovered and introduced by nurseryman Gunter Horstmann from Schneverdingen, Germany as a witch’s broom mutation on Abies pinsapo ‘Glauca’ , or so the story goes, but at Buchholz Nursery the broom is more gray-blue than the ‘Glauca’s’ silver-blue. According to the Missouri Botanical Garden’s website, “The specific epithet of pinsapo may come from Spanish pino meaning ‘pine’ and sapo meaning ‘fir’ in reference to the tree being a fir in the pine family.” That may be true, but I imagine that the southern Spanish species is noted for its short, sharp, pin-like needles, thus “pin fir.” A different species, or a variety of pinsapo, is Abies marocana from the Atlas Mountain foothills in Morocco, which occurs just a short distance away (as the pollen flies) on the continent of Africa. ‘Horstmann’, if it is deemed to be a “dwarf,” is nonetheless a vigorous example, but it is the only A. pinsapo cultivar that we propagated this winter, eschewing other witch’s broom varieties that are just too miniature to be profitable.

Abies koreana ‘Nanaimo’

No conifer collection would be complete or considered valid if it excluded the garden-worthy species of Abies koreana. It is a small-to-medium-size tree according to the literature, but I have a 45-year-old ‘Nanaimo’ – which grows like the type – and its only 20′ tall (6 m). I’m frequently interested in the short plant descriptions provided by The Hillier Manual of Trees and Shrubs, but I’m baffled by the entry for Abies koreana where plant explorer/botanist E.H. Wilson is credited for first describing the species…with 1905 as the date of introduction. However, Wilson was in China in 1905 collecting for the Veitch Nursery firm and his trip to Japan, Formosa and Korea was not undertaken until 1917-1919 under the auspices of the Arnold Arboretum. My latest edition of the manual was published in 2019, and I also found the last sentence to be strange: “A tall-growing but very poor form is in cultivation.” Personally I’ve never seen a poor form, so my advice is to go cultivate a different one.

Abies koreana ‘Ice Breaker’

In any case we grafted four cultivars of Korean fir: ‘Silberzwerg’, ‘Alpine Star’ (known as ‘Alpin Star’ to the Euros), ‘Gait’ and ‘Ice Breaker’. Both ‘Silberzwerg’ and ‘Ice Breaker’ originated as witch’s broom mutations on A.k. ‘Silberlocke’, and they were absolutely hammered by our 116 F heat dome a couple of years ago. They are favorites for conifer aficionados due to the glitzy silver of the needle-undersides which curve around the shoot, but the silver scorched in full sun while those in shade were fine. I felt we needed some restraint on our production of “Ice Breaker,” even though we grafted 238, because the relatively new selection is becoming common in wholesale nurseries, especially in Oregon. Graft takes are always high at Buchholz Nursery, but also for the competition. ‘Ice Breaker’ was discovered in East Germany by Jorg Kohout who prefers that we call it Kohout’s ‘Ice Breaker’, but I feel that his name shouldn’t be included, so we don’t. In addition to our ‘Ice Breaker’ from grafts onto Abies firma, we also root about 1,000 per year. The cutting production surprises visitors who suppose that it would be difficult to root, but not so at all.

Abies koreana ‘Gait’

Abies koreana ‘Gait’ doesn’t have a very commercial name but it is a wonderful narrow, upright dwarf with a prolific cone set. A three-foot tree can produce up to fifty cones and a well-grown specimen is as ornamental as any decorated Christmas tree. As with ‘Ice Breaker’, ‘Gait’ will strike root from cuttings in winter, and actually all of the A. koreana dwarves root very well. It was selected in The Netherlands in about 1990, and we acquired it about ten years later; we always sell out.

Abies koreana ‘Alpine Star’

Abies koreana ‘Alpine Star’ is a miniature evergreen bun with a spreading form. Dark green needles on short stems provide the backdrop for a constellation of tiny white buds that look like the night sky. It looks very cute in a container, trough or an alpine garden, and we pioneered the package of ‘Alpine Star’ in our pumice planters. And again, like most Abies koreana cultivars, it roots readily but it is much slower and diminutive on its own roots versus a graft on a vigorous seedling.

Abies koreocarpa ‘Hurricane Blue’

An Abies we were not successful at rooting is the hybrid between A. koreana and A. lasiocarpa. We began producing the cross about 40 years ago, with starts coming from Germany. It wasn’t commercially popular because there was no specific cultivar name; the tree was an irregular upright with dull gray-blue needles and basically amounted to a BIO plant (Botanical Interest Only). Eventually, through further breeding, and accompanied with a specific name change to Abies x koreocarpa, the Germans introduced a cultivar named ‘Inga’, which was also named ‘Hurricane Blue’. I kept the two separated for about 10 years until I became aware that they were synonymous and we chose to keep the ‘Hurricane Blue’ name. No matter what you call it, the selection is fantastically blue, dense, with a perfect Christmas tree shape. It is dwarf but not miniature; it is a money-maker. In the garden it will form a 5′ cone in 10-12 years and is hardy to -30F, USDA zone 4. In an article of the International Dendrology Society mention is made as to other A. koreocarpa cultivars such as ‘Diskus’, ‘Festival’, ‘Hobbytime’ and others which I do not grow. As for ‘Hurricane Blue’ it was suggested by the IDS, “Possibly of North American origin, it was first listed by Buchholz & Buchholz of Oregon in 2009.” I was growing it then, but it certainly did not originate in my nursery. Another source, one of my customers, says it “was likely created by Wittbold-Muller Nursery in Germany.” I believe the latter because I have visited that nursery twice and I know he was working on hybrids, or at least seedling selections from that particular hybrid. ‘Hurricane Blue’ is a catchy name, but I wasn’t aware that hurricanes could have a color. The name Abies is of Latin origin, probably referring to Abies alba, a “silver fir,” and it was established by botanist Miller in 1754, perhaps “a result of Virgil using the word Abies for the timber from which the ribs of the Trojan horse were constructed.” I always assumed that the Abies in question was A. equi-trojani for the wooden horse but many botanists consider that to be Abies nordmanniana subspecies or variety equi-trojani.

Abies squamata ‘Flaky’

Buchholz Nursery introduced Abies squamata ‘Flaky’ in the late 1980s, and its origin was documented in Buchholz Plant Introductions (Part 5), a twenty-part Flora Wonder Blog produced from June 23, 2023 – December 13, 2023. Abies squamata was discovered by E.H. Wilson in 1905 and introduced by him in 1910 when he was employed by the Arnold Arboretum of Harvard University. It is noteworthy for its reddish-brown exfoliating bark and is the highest altitude Abies in the world (up to 15,419 ft, 4,700 m). According to the International Dendrological Society, “A cultivar [‘Flaky’] introduced from the Flora Wonder(tm) range of Buchholz & Buchholz c. 2009, this is likely a naming of material ultimately traceable to a Wilson original.” That’s probably correct, but we were producing it about 25 years prior to 2009.

Abies nordmanniana ‘Pendula’

We grafted a couple of Abies nordmanniana cultivars, ‘Golden Spreader’ and ‘Pendula’. The ‘Pendula’ can be staked to the desired height (5-6 ft is good) and then topped so the weeping branches will spill downward in a balanced fashion. From a distance it might resemble the common, “Weeping Norway spruce,” Picea abies ‘Pendula’, but upon close inspection the Abies’s foliage is softer and more aromatic, and certainly less prickly to the touch. This weeping form of the “Caucasian fir” has been in cultivation since 1870 but I’ve only encountered it in specialty gardens and arboreta in America, while it is a little more common in Europe. The species’ epithet honors Alexander von Nordmann (1803-1866) a Finnish naturalist who discovered it around 1836-1837. In Oregon it is commonly planted as a Christmas tree because of the rich-green foliage that persists on the cut tree longer than many other conifers.

Abies nordmanniana ‘Golden Spreader’

Abies nordmanniana ‘Golden Spreader’ looks and grows as the name implies, but mature specimens almost inevitably assume a leader. The needles are lush, butter-yellow, and surprisingly our oldest 35-year-old specimen resisted scorch in our hellish 116 F heat dome which occurred when the new growth was still soft at the end of June 2021. ‘Golden Spreader’ was found as a seedling in The Netherlands in about 1960 by nurseryman S.N. Shoots, a name I covet over my own. S.N. Shoots – like the panda that eats, shoots and leaves.

Abies concolor ‘Sherwood Blue’

The Abies cultivars that we grafted this season represent just 10% of those in the collection, but we were trying to focus on the most profitable. The production room is fun to enter during the Abies period, when the scion-cutter comes in from the cold and is greeted with a mountain aroma. I don’t graft anymore, nor do I cut most scions now, but I estimate that I have “handled,” one way or another, at least 250,000 Abies in my career. It resulted in gray hair and a stooped back, but it was always pleasurable to propagate the True firs.