Large Conifer Species, Tiny Selections

A recent Flora Wonder blog focused on some curious plant oddities that one can find in our arboretum. These are living creatures that fascinate flora aficionados such as myself, while I'm fully aware that most seeking to plant a tree would prefer something more normal, green and vigorous, a bush or tree that gets the job done, and one that maybe flowers once a year besides.

Sequoiadendron giganteum 'Julian'

Well, I've grown plenty of normal green plants, millions I suppose, but I'm always fascinated by the range of size variation that the plantsman encounters while he toils to make a living. On the wall above my desk is a photo of Sequoiadendron giganteum 'Julian', a miniature “Giant redwood” discovered by Nelis Kools of Deurne, The Netherlands. Kools houses the national Dutch collection of Sequoia, Sequoiadendron and Metasequoia, so naturally he would be fascinated with the most massive genus on earth and also with its tiniest cultivar. As P.T. Barnum did with the dwarf human Tom Thumb, perhaps Kools could charge the public a euro each to see his little runt. Remember that a humongous trunk section of the General Noble tree was displayed at the 1893 World's Exposition in Chicago, and many a Midwesterner doubted its authenticity, but they all enjoyed the freak show. Years ago a Dutch grower visited my nursery and he brought a 'Julian' as a gift from Kools, but the visitor was already a week in America and the little plant was completely dry and did not survive, so I've never owned a 'Julian', and at this point I don't really care.

Sequoiadendron giganteum 'Little Stan'

Sequoiadendron giganteum 'Little Stan'

Sequoiadendron giganteum 'Little Stan'

But, I have succeeded with another Kools redwood seedling, Sequoiadendron giganteum 'Little Stan', and it's actually in our production...propagated by rooted cuttings in winter. It is a little faster than 'Julian', but 'Little Stan' is still only 24-30” tall in 10 years. The dwarf is blue-green in color and juvenile in appearance, in other words not with normal Sequoiadendron foliage. I would rate 'Little Stan's' winter hardiness at USDA zone 8 (10 F), even though it has survived at 5 F, but the issue is how much damage the juvenile foliage can endure, and if the gardener wants to deal with an unsightly tree. In any case the grower should probably not propagate 'Little Stan' by grafting onto seedling rootstock, as that might – probably would – push the dwarf into more vigorous, uncharacteristic growth. Indeed, I had an older specimen in my Conifer Field, at about 15 years of age that was on its own roots; sadly the bottom “Little Stan” portion died and the top shot upward about 4' of normal Sequoiadendron growth. I reported (with photo above) the disaster to Kools, and that provided even further proof to him that America is just way too aggressive. I dumped the entire “ruined” tree, although in hindsight I probably should have kept it for “scientific reasons.”

Sequoia sempervirens

Cedrus atlantica 'Glauca'

Cedrus atlantica 'Glauca'

I admire the art of bonsai as much as anyone; but my grandmother didn't – she deemed that the wire used to create “contortions” was akin to “crippling children.” I ummed and nodded, not wanting to create controversy, but I disagreed because, as I said previously, I'm fascinated to explore the extremes in the Kingdom Plantae. Imagine the tallest tree on earth, Sequoia sempervirens, rendered in vastly reduced form via bonsai. Or, consider another enormous species, Cedrus atlantica, and its well-known 'Glauca' cultivar thriving in a shallow dish as the specimen (photo above) does at the Pacific Rim Bonsai Collection in Washington state. I doubt that the casual visitors to this “Reduction Park” are aware of the enormity of the subject species in their native haunts.

Abies procera 'Glauca'

Abies procera 'Blaue Hexe'

The “true firs” are in the Abies genus, a name from ancient Latin that means the “rising one,” referring to a tall tree or ship. The tallest species of Abies on earth, A. procera (“Noble fir”), comes from the mountains of Oregon and Washington, and the specific epithet means “very tall or long.” The world champion (at 278') grew at Yellow Jacket Creek in Washington state, but a few years ago it lost its top 27' in a wind storm; nevertheless it remains as the champion tree because of its bulk. Contrast that behemoth with one of the tiniest conifers, the cultivar 'Blaue Hexe' which means a “blue witch” in German. Hexe is short for Hexenbesen meaning “witch's broom,” and the introduction originated in the 1960s at Boehlje Nursery of Westerstede, Germany. My oldest specimen was devastated in our record heat (116 F) last June, and though it wasn't technically dead, it was edited anyway because I couldn't stand to see it in misery. Fortunately I also grow a few in containers in the shade and they survived with no damage.

Picea sitchensis

Picea sitchensis 'Sugarloaf'

Picea sitchensis 'Silberzwerg'

Even taller than the Noble fir is the “Sitka spruce,” Picea sitchensis, another West coast native that is the third tallest tree (96m, 317 ft), behind only Sequoia sempervirens (379 ft) and Pseudotsuga menziesii (329 ft). Native Americans made great use of the species before the white man showed up to “discover” it, namely Archibald Menzies in 1792, then introduced by David Douglas in 1831. We have grown a number of cultivars – 'Papoose', 'Tenas' and 'Wiesje' – and they more or less look alike, and all readily strike root from winter cuttings. To my knowledge they originated from witch's broom mutations, and when on their own roots they form round balls at less than 3' in height and width. Another dwarf is 'Sugarloaf'*, a seedling discovered on Sugarloaf Mountain by the late Bill Janssen of Washington state. The only cultivar currently in our production is 'Silberzwerg' (“Silver dwarf”) because it displays more glittery pizzazz than the others. It was found as a witch's broom at Oltman's Nursery, eastern Friesland, Germany.

*The origin of this cultivar is an example of the numerous false assertions/assumptions made in the recent publication of the Royal Horticultural Society's Encyclopedia of Conifers which states that it was “introduced by Buchholz & Buchholz Nursery, OR, USA.” It was not.

Metasequoia fossil

Metasequoia glyptostroboides

The Metasequoia genus was discovered by T. Kan in central China in 1941 and it was introduced to cultivation in 1947. Previously it had only been known from fossil record, so the “living relic” created a stir in the botanic community. Portland, Oregon's Hoyt Arboretum was among the first to plant the monotypic genus and a plaque celebrates the fact that the Hoyt tree was the first in the Western hemisphere to produce cones in “about 6 million years.” I have a crappy little rock with a Metasequoia fossil from the Columbia River Gorge, but the foliar imprint is not clearly obvious, at least not for me. Apparently its previous existence in Oregon was made known when a fisherman ducked for cover under a cliff during a downpour and found the fossils. I wish I knew the location as I would like to see them for myself, and I also wish I could see the living stand in China, but that probably won't happen. While the Hoyt tree was allegedly the first to cone, I wonder where one can find the largest specimen outside of China. Umm?

Metasequoia glyptostroboides 'Miss Grace'

Metasequoia is an extremely vigorous conifer, obviously too large for most landscapes, but fortunately we now have dwarf cultivars that are horticulturally worthy. Our 'Miss Grace' was of witch's broom origin while the similar 'Bonsai' was discovered as a seedling. The Hillier Manual of Trees and Shrubs describes 'Miss Grace' as “a small, elegant cultivar with a compact habit and weeping branches...” but if you saw the original graft they might change that description.

Metasequoia glyptostroboides 'North Light'

Metasequoia glyptostroboides 'North Light'

Buchholz was the first American company to produce Metasequoia glyptostroboides 'North Light' (AKA 'Schirrmann's Nordlicht'). Hillier describes it as “A very compact selection, though too recent an introduction to judge ultimate height.” Well, I can help with that. Posing in front of 'North Light' is my 5' 4” tall wife. I don't remember the exact year I received the first scions, but I guess 13-15 years ago, and they were sent by the aforementioned Nelis Kools. The German Winifried Schirrmann discovered the witch's broom on the variegated cultivar 'White Spot', and it was Kools who first introduced 'North Light'. Everyone agrees that the mutation is more garden worthy than the host mother, but you can see it is quite vigorous too. Kools saw my plants two years ago and he declared them to be the largest in the world, and I think it pained him a little that his had not grown as much. Hillier describes the colour accurately: “The foliage emerges creamy white before turning a soft pale green.” I mention again that we scorched at 116 F last June when the foliage was more white, but 'North Light' kept on shining with absolutely no damage.

Metasequoia glyptostroboides 'Daweswood Tawny Fleece'

A new “Dawn redwood” cultivar for me, Metasequoia glyptostroboides 'Daweswood Tawny Fleece', has an awkwardly long name but so far I like the plant. I expect it will be equally vigorous as 'North Light' judging by my first grafts. Last winter's scions were literally the size of toothpicks and today they are almost one foot wide. Of course plants are pushed in the greenhouse with fertilizer and lots of water...or maybe I'm just a damn great grower. The “Daweswood” part to the cultivar name is due to its discovery as a witch's broom at the Dawes Arboretum in Newark, Ohio.

Tsuga canadensis

Tsuga canadensis is the eastern counterpart to our western hemlock, Tsuga heterophylla. They are specifically separated for valid (boring) botanical reasons, but to most of us they are huge evergreens that look alike. T. canadensis is native to Canada – duh – but the range also extends from Canada to Maine, south to Georgia and Alabama. Keith Rushforth in Conifers makes an interesting observation: “The species is extremely tolerant of shading. All of the current season's growth, including the leading shoot, is pendulous and this is considered to be an adaptation to shady sites, as it allows an increased interception of the available light. The leading shoot only becomes firm and woody during the autumn/winter period, when the broadleaved trees are leafless.”

Tsuga canadensis 'Betty Rose'

Tsuga canadensis 'Betty Rose'

The Canadian hemlock species is well-known for a couple of hundred cultivar selections that originated as witch's broom mutations or as unusual seedlings. Maybe my favorite of the dwarves is 'Betty Rose' which produces cream-white, and sometimes pinkish new growth. It is described in the literature as miniature, petite etc. but my oldest specimen (cutting grown) is nearly 10' tall and about 7' wide at 40 years old. It is happily sited in the original Display Garden with afternoon shade and it escaped any damage from our June hellish heat blast. “The original plant was found in the wild in 1973 near Vanceboro, Maine by Francis J Heckman of Amber, Pennsylvania and named for his wife,” according to the American Conifer Society website. I encourage you to visit this site – after first finishing my blog! – and you can see the late Mr. Heckman standing next to the original that's planted in front of his house. I only wish that old Heckman would have moved aside and let dear Betty Rose pose instead. Betty Rose – what a lovely name.

Tsuga canadensis 'Cole's Prostrate'

Another Tsuga canadensis favorite is 'Cole's' or 'Cole's Prostrate', a very slow creeping selection that was collected in the wild by H.R. Cole in 1929 from Mt. Madison, New Hampshire and transplanted to his nursery in Massachusetts. In the photo above Haruko is posing next to an old specimen at the Arboretum Trompenburg in Rotterdam, The Netherlands. I don't know how old their plant is, but the photo was taken B.O.C. (Before Our Children) which was nearly twenty years ago. Hopefully it still thrives.

Tsuga heterophylla

Tsuga heterophylla is the largest species of hemlock and is the state tree of Washington (Oregon's is the “Douglas fir,” Pseudotsuga menziesii). While Tsuga canadensis can reach 175' (53.3m), the Western hemlock can grow to 258' (78.9m) in height, and the latter species can live to over 1200 years. The champion grows in Prairie Creek Redwoods State Park in California, so it's obviously attempting to keep up with its redwood brethren.

Tsuga heterophylla

When I was twenty, tired of being poor with a student loan, I dropped out of college to work for good pay at a lumber mill. My co-workers were uneducated ruffians, but I was able to gain their respect by working my ass off, and I am probably the only human in the history of lumber mills to work for two years straight, never late or missing a day. Anyway, manning the chain where you pulled each board onto its proper pile, I could always tell the hemlock from the Douglas fir because the Tsuga was half again more heavy. Fortunately only one out of about 100 was a hemlock.

Tsuga heterophylla 'Thorsen'

Perhaps the best known cultivar of Eastern hemlock is 'Pendula', “Sargent's Weeping hemlock.” But our Western hemlock has a weeper too, named 'Thorsen' (AKA 'Thorsen's Weeping'), and it is much more refined than its Eastern counterpart. It can be grown as a spreading groundcover or staked into a small weeping tree, and in the collection we grow them both ways. Staked trees are generally more valuable, so we grow ours to about 4' tall then top the leader. In 10 years the pretty green pillar will be about 2' wide. 'Thorsen' appeared in the trade in the mid 1980s and I got my start from the late Dick Bush of Canby, Oregon, a noted hemlock collector. Maybe he knew of the cultivar's origin, but no one else seems to.

As I walk through my gardens I see numerous cultivars that could have been added to this blog – large species with tiny selections, and maybe another day I'll limit discussion to just evergreen and deciduous broadleaved species. I'll repeat the story of the visitor from long ago: he didn't really care for my nursery because nothing looked...“normal.”