Buchholz Plant Introductions (Part 9)

My confessional continues, an attempt to document the multitude of plant introductions that have sprung from my green loins. Plenty of them have proven to be better forgotten, nevertheless one can occasionally find them in American arboreta, private nurseries and gardens, where a grower or two might champion the introduction for its few qualities.

But then there is a sizeable portion of the Buchholz plant introductions that are currently very popular and have been produced by the thousands from around the world.

Of course there exists the inevitable third group, the inbetweeners that rise well above the duds, but that are not garden-center favorites. In this category are many useful and attractive plants that serve good purpose, even though I sensed at the time of introduction that they would never become best-sellers.

Acer circinatum 'Sunglow'

Acer circinatum 'Sunglow'

The original Acer circinatum 'Sunglow'

Today's blog will discuss maples only, and I'll draw out examples from all three groups. The so-so introductions can include all of the Acer circinatum cultivars, because the West Coast's “Vine maple” species does not perform well in most of the summer-humid portions of the United States, which is mostly where we ship our plants. They're even problematic in our Oregon growing conditions because they can attract powdery mildew, and unless you have a significant crop – which I never do – you don't get around to applying fungicide to a few scattered individuals. That's a shame because a very impressive introduction, A.c. 'Sunglow', can look fantastic if well-sited in moist, well-drained loam and some afternoon shade. For the 'Sunglow' entry Vertrees/Gregory in Japanese Maples begins by calling it “This distinctive cultivar...” and ends by concluding “It is very different from any other A. circinatum cultivar...” Actually it is not, as it is similar to A.c. 'Sunny Sister', a sister seedling.

Acer circinatum 'Sunny Sister'

Acer circinatum 'Sunny Sister'

The late Floyd McMullen of Portland, Oregon had selected about seven of these unusual A. circinatum seedlings which he generously gave away to plant friends. I acquired one and called it 'Sunglow' in about 1994, then another in about 1998 which I named 'Sunny Sister', but I don't know what became of the rest of them. The original 'Sunglow' is planted in full sun in the nursery's Short Road section and, since it struggles somewhat by mid summer*, it is only 6' tall by 8' wide at 30 years of age. The original 'Sunny Sister' was sold long ago, but an early propagant still hovers in the Blue Forest. It handles the full sun much better than 'Sunglow' and it currently rises to 10' tall and stretches to 15' wide. Both originals were of the same age, from the same batch of vine seedlings that the amateur McMullen was playing with. Sadly, Mr. M. passed before I acquired two of his seedlings and I was never able to meet the man, but he was survived by his wonderful wife Kathleen who was sharp and beautiful, and she taught piano lessons well into her 90s. The handful of times that I met her, she was pleased to hear that I admired and named two of her husband's seedlings, as if that somewhat brought him back to life.

*We all struggled when we reached 108 F (42 C) last week.

Acer circinatum

Acer circinatum 'WB Hoyt'

Peter Gregory with Acer circinatum 'WB Hoyt'

Acer circinatum 'WB Hoyt'

Acer circinatum 'WB Hoyt'

Neither of the previous two Vine maples will ever be commonly grown, not even in Oregon gardens, but the avid Northwest plantsperson can certainly find a place for them, especially in a collection that features or promotes the use of natives. Probably lost to obscurity, though, is a dwarf that originated from a witch's broom at Portland, Oregon's Hoyt Arboretum. I was alerted to its existence by the conifer guru from Vermont, Greg Williams, who was visiting Oregon nurseries and gardens in about 1995. It took me some time to locate the broom on my own, for it occurred low to the ground amongst the weeds and leaf litter, and I confess that upon my rediscovery I was a little disappointed with the mere glob of congested foliage. Nevertheless I snitched a few sticks and labeled the grafts with 'W.B. Hoyt', a code name that was never improved...because frankly it wasn't deserving of a more inspired name. The world of maple cultivars already included Acer circinatum 'Little Gem' which was sourced from a witch's broom discovery in Stanley Park, Vancouver, British Columbia about 40 years prior, and 'W.B. Hoyt' added no discernable improvement. Furthermore, the Hoyt broom got mixed up somewhere along the way with the aforementioned 'Sunny Sister', and that screw-up either occurred at my nursery or from one of my customers. 'W.B. Hoyt' should be totally green, but the one that was accessed by the Hoyt displayed the orange new foliage of 'Sunny Sister', but I never knew whence they sourced it. I wonder if the true 'W.B. Hoyt' exists anywhere anymore, but I certainly don't have it. I regret that it was possible my company fouled the nomenclature and contributed to its demise, but at least I have a photo of the late author/friend Peter Gregory gleefully admiring the broom. I explained to him that I further observed, after at least a decade of visits, that the broom and the parent tree leafed out at least 3 weeks apart from each other, and that they also displayed their fall color about three weeks apart as well. Now, I have forgotten which event occurred first, the chicken or the egg?...err, the mutation or the parent. I cannot return to ascertain the chronology because the last time I revisited the phenomenon, the parent tree and its mutant broom had both disappeared, and Martin Nicholson, the Curator of the Hoyt revealed that it had died, and now they have installed a minor Syringa collection in the A. circinatum's stead. I gloomed that it was a lost opportunity to demonstrate the marvels of horticulture, maybe some explanation to the public – children I hoped – about the Origin of Species. No, not species, but of cultivated variants. The further lesson is that nature's whims, such as a witch's broom mutation, might possibly be short-lived, you never know. Maple expert Peter Gregory was here one day, then gone the next...just like the 'W.B. Hoyt'.

Acer circinatum 'Baby Buttons'

Acer circinatum 'Baby Buttons'

Another Acer circinatum witch's broom that niggled along in our production was A.c. 'Baby Buttons', and I still have a nice specimen at Flora Farm, and a couple more at the nursery in containers. It is far more dwarf than the others, but unfortunately it is prone to branch die-back, not uncommon amongst many broom-origin plants. The mutation was spotted along I-205 by an ex-employee, and it's amazing that the volleyball-sized broom was noticed at all, since autos speed along at 65-75 MPH on the interchange. One supposes that millions more aberrations occur in the wild that no one documents or propagates, just as a man or woman might ponder what would have happened if a different “fish in the sea” was chosen instead of the One that we ended up with. For me A.c. 'Baby Buttons' resides halfway between the so-so and dud level, but when happy it is a cute little gem, so I don't regret its inclusion in the pantheon of Buchholz plant introductions. Last propagated about 5 years ago and just so you know, I've given up on it.

Acer griseum

Acer griseum

Acer griseum

In my 43 years of nursery ownership I have seen Acer griseum, the “Chinese Paperbark maple,” go from being considered rare and highly sought after to ubiquitous and commonly used as a street tree, and not always on the best of streets either. The use of A. griseum was initially limited because the seed was considered difficult to germinate. Growers such as Mark Krautmann of Heritage Seedlings, Oregon, figured it out and I have seen his crops of thousands of healthy sprouts thriving in his greenhouse environment. Mark began by planting out an allee to source his seed, and now the mature specimens are very impressive, or at least they were ten years ago when I saw them last. Krautmann doesn't hurry the germination process, rather he imitates what happens in nature. The seed is dumped in wooden barrels and left to simmer for a couple of years among rotting leaves and well-drained soil, then they are planted into plugs where they grow straight and tall. Before seedlings of A. griseum were plentiful, I grew my first trees in a more laborious manner by grafting onto Acer rubrum, for which it is surprisingly compatible.

Acer griseum 'Susanna'

Acer griseum 'Susanna'

I've grown a couple of Acer griseum “cultivars,” one skinny and the other fat. The fat-boy was named 'Susanna', and the original tree features a broad canopy. It was a chance seedling growing at Susanna Farm Nursery, a long-time customer of ours from Maryland. I've never encountered the species in the wild so I don't know how unusual 'Susanna' is, but its form and peeling bark is most impressive in winter. I have one planted at Flora Farm, now about 12 years old, so I'll have to be patient to see how it develops.

Acer griseum 'Narrow Form'

Acer griseum 'Narrow Form'

A batch of Acer griseum seedlings purchased from Heritage led to the discovery of one tree with a particularly narrow canopy. It never received a formal cultivar name beyond me temporarily calling it 'Narrow Form'. I watched the individual for a number of years, and visiting plantsmen would enthuse over the unique find. One autumn in a moment of weakness I relented and agreed to sell the original, but I first grafted some apical shoots so I could continue with the “cultivar.” To my dismay, however, the propagules did not resume the narrow form, they grew just like any other A. griseum, or at least when young. One was kept at Flora Farm in the maple section, but it's clearly not as narrow as the original. Of course I regret parting with my discovery – I guess I had a payroll to meet – but maybe it's good to be done with wasting my time on a clone that doesn't live up to its name. Sadly I don't remember who was the original's customer so I can't report on its progress, and I'm just left with a bittersweet memory.

Acer campbellii

Acer campbellii was named for the English explorer and botanist Archibald Campbell and it is native to Himalayan foothills up to 9000', and as is typical of these Asian mid elevations, the species is only barely hardy in Oregon (USDA zone 7). I have seen it in the wild – probably – but then I haven't been trained in botanical tree identification. I remember a Makalu trek in Nepal where the maple species were just beginning to leaf out, and the spring shoots were colored a delicious mahogany-red. Twenty five years ago I was given an A. campbellii seedling from the late, eclective propagator and grower Bill Janssen of Washington state. I didn't want it really because it wouldn't be commercially viable, that much I was certain. Besides, Janssen was known to be horticulturally challenged at times with his plant ID, so I wasn't sure what I was getting.

Acer campbellii 'Exuberance'

Acer campbellii 'Exuberance'

My Acer campbellii – if that's really what it was – prospered in my greenhouse but I never trialled it out in the garden. When a few customers saw and admired it I began propagating, and conveniently the species is compatible with Acer palmatum. However attractive it was, sales were still weak because it was perceived to be borderline hardy, and that it was a species that grew too large to fit into most gardens. For years I kept just a couple of plants at the nursery, and the handful that we propagated went to California garden centers. Fresh spring leaves are wildly marked with cherry-red, then mature to a bronze-red with prominent lime-green veins. For me this maple overflows with joy and enthusiasm, hence 'Exuberance', a word that originates from Latin meaning “an overflowing supply of milk from the udder of a cow or goat.”

Acer tataricum

Acer tataricum

Acer tataricum subsp. ginnala

Acer tataricum subsp. ginnala

The Amur River

The same Mr. Janssen who gifted me the Acer campbellii seedling also played around with seed of Acer tataricum subsp. ginnala 'Emerald Elf', and he presented me with a seedling he believed was even more dwarf than the parent. The little 5-year-old bush was less than attractive when I received it in August but I warmed up to it when it flamed to brilliant red that autumn. Now, at about 25-30 years of age, it has been growing in the rockery of the nursery's Blue Forest and currently measures 3' tall and wide. It looks healthy and the tiny leaves shine, and our recent 108 F scorcher didn't bother it at all. About 10 years ago I passed it on my way to get cuttings of something else and I noticed that it had sprouted a number of 1-2” shoots, but never before had it behaved so enthusiastically. On a whim I stopped and harvested about 50 cuttings, and to my surprise they all rooted. Now, propagating is easier since we can source the cuttings from more luxurious greenhouse-grown plants, but as I approach my career's end we have abandoned most summer cutting production altogether. I cannot compare my 'Little Elf' to the seed parent 'Emerald Elf' as I've never grown the latter. Fall color can be intense but it seems to last only a couple of days before the leaves turn brown and drop, and I suspect that no Buchholz employee, past or present, could tell you where the original is planted. Acer tataricum is native to southeastern Europe and southwestern Asia, while the subspecies ginnala extends from China, Japan, Korea to eastern Siberia, hence its common name of “Amur maple.” The Amur River is the world's 10^th longest river at 2,761 miles (4,444 km) and is known in Chinese as Heilong jiang, or “Black Dragon River,” and at the end of its course it empties into the Strait of Tartary.

Acer palmatum

All of the maples discussed thus far in this blog have been either mildly successful commercially or complete failures, not that the plantsman necessarily judges the worthiness of a tree by how it fares commercially. The common denominator for their limited success is that none of them are Acer palmatum cultivars, as that's the species that Buchholz Nursery has built itself around and comprises about 90% of our maple sales.

Acer palmatum 'Yellow Cascade'

Acer palmatum 'Yellow Cascade'

Acer palmatum 'Yellow Cascade'

I'll finish this Part 9 with two Acer palmatum cultivars that are very popular with our customers: A.p. 'Golden Falls' and 'Yellow Cascade'. Both originated as seedlings from A.p. 'Ryu sei' in about 2008, and they resemble the mother tree with its compact weeping habit. We germinated about 1,000 seedlings and approximately 20% displayed the pendulous characteristic, while the remainder were normal-palmatum uprights. Out of the 200-or-so weepers, two featured yellow foliage and were set aside to observe, while the remainder were labelled 'EX Ryu sei' and sold as random green prostrate seedlings.

Acer palmatum 'Golden Falls'

Acer palmatum 'Golden Falls'

The slower of the two selected seedings is A.p. 'Yellow Cascade', but not by much. In August the foliage of both appears light green, but in early spring the 'Yellow Cascade' emerges with a soft yellow color, while 'Golden Falls' is a strong orange; similar but different, like two lovely sisters. We produce the 'Golden Falls' in the greater number, at least for now, and I look forward to harvesting seed from it should it oblige, and wouldn't it be incredible if a red weeper sprouted?

Haruko with the Queen's Green Canopy Plaque

Queen Elizabeth

I was honored last fall to participate in The Queen's Green Canopy, the Platinum Jubilee of Her Majesty Queen Elizabeth. She served her country for 70 years and as a final tribute she promoted the planting of thousands of trees. The aim was to encourage everyone to plant “the right tree in the right place, at the right time, so they continue to thrive for generations to come.”

Planting the Queen's tree with Patrick Franklin of Bartlett Tree Experts

Robert Barlett (Right), Owner of Bartlett Tree Experts 

I chose to plant a 7' weeping specimen of Acer palmatum 'Golden Falls' and the plaque to mark the tree was provided by Bartlett Tree Experts, the new custodians of the Flora Farm arboretum.

Geraint Richards with Acer palmatum 'Golden Falls'

Two weeks ago I was pleased to host Geraint Richards at Flora Farm. He is the Head Forester to the Duchy of Cornwall and to His Majesty The King, so of course he was instrumental in launching The Queen's Green Canopy. Mr. Richards was delighted to meet the 'Golden Falls' maple (and revealed that King Charles adores Japanese maples). My tree was declared “the furthest one away from England,” and for me it symbolizes my journey through life, with “Plants from the Best Corners of the World.”