IDS TOUR – California 2019

 

As a member of the International Dendrology Society (IDS) I'm entitled to their annual yearbook, and I received my 2019 copy yesterday. Another benefit of the “Tree Society” is that a member can attend an IDS tour, although I never have, and the tour reports are presented in the following yearbook. Who knows how the IDS will flesh out its pages in the future due to Covid restricting travel for most of 2020?

Most of the IDS members are European, and well-heeled at that, but it's fun to read about their trips and how they balance luxury with the rusticity of good ol' nature. I read with particular interest about two IDS American members who led about 30 Euros on a 27 day tour of California, especially since I've been to nearly every place they visited, some quite a few times. Many Europeans harbor ill feelings towards Americans, but there's no way anyone could gripe about the wonderful assortment of trees native to the Golden state. The tour report was rendered by Professor Dr. M.A. Robischon of Humboldt Universitat zu Berlin, and more about Humboldt later.

Corymbia ficifolia

Corymbia ficifolia

Since the California tour began in San Francisco, obviously a visit to the San Francisco Botanical Garden was in order, and a tree mentioned early in the article was Corymbia ficifolia. I have learned that arboreta must stay nimble with their nomenclature because just a short time ago Corymbia used to belong to the Eucalyptus genus. The tender “Ghost gum” from southwest Australia was separated from Eucalyptus because it possesses compound terminal flowers, and C. ficifolia's are scarlet-colored and borne in large corymbs at the ends of the branches. The first time I saw the tree I was most taken with the furrowed trunk, not the flowers, because I guess it was in autumn with flowering finished.

Arbutus 'Marina'

Arbutus 'Marina'

My first encounter with Arbutus 'Marina' was in the same botanic garden, but back then it was known as the Strybing Arboretum. Since San Francisco now administers the arboretum in its Parks system, there is a noticeable lack of funding, or so grumble the employees who preferred the old days. In any case the parentage of 'Marina' was not certain, but the 2019 edition of The Hillier Manual of Trees and Shrubs proclaims it to be x reyorum which is A. x andrachnoides x A. canariensis, so a triple hybrid then. Hillier reveals that it “Performs best where summers are warm, especially in maritime gardens. Grown in California, USA, since at least 1933.” I saw 'Marina' used as a street tree – I think in nearby San Rafael – and I had an instant urge to move there.

Dacrydium cupressinum

Dacrydium cupressinum

Thomas Frederic Cheeseman

IDS Author Robischon mentions Dacrydium cupressinum growing in nearby Golden Gate Park, but I remember seeing the “Rimu pine” inside the Strybing as well. It's not a pine at all; it is in the Podocarpaceae family from New Zealand. Hillier relates that the graceful conifer was considered by the botanist Thomas Frederic Cheeseman (1845-1923) to be “as beautiful and attractive as any tree in New Zealand.” I agree, and I used to propagate (via rooted cuttings in winter) and sell it early in my career. Eventually I discontinued it because of lack of hardiness – it needed to stay above freezing – but also because cutting-grown trees, at least when young, tended to flop like limp branches. The young man (above) in the blue shirt is me, I guess from about 25 years ago when my hair was brown.

Alexander von Humboldt

Ceroxylon quindiuense

Ceroxylon quindiuense

Ceroxylon hexandrum

One last plant that I'll describe from the Strybing – sorry I prefer the old name – is the “Andean wax palm,” Ceroxylon quindiuense. According to Robischon, it was “discovered for western science in 1801 by Alexander von Humboldt, which is also the tallest palm tree known.” I wrote about it in a previous blog, that it is a fun tree and the symbol of Columbia:

I encountered it at the Strybing Arboretum of San Francisco and I was certainly taken with the whimsical nature of the trunk. The related species hexandrum was growing nearby, also barber pole-like but not quite as exaggerated. Of course the trunk markings are the result of exising leaf fronds which is common with palms. The “Andean Wax Palm” is native to montane forests of Columbia and Peru and can reach an astounding 200’ tall. The genus name is derived from Latin cera for “wax” and Greek xulon for “wood.” In the past the stem wax of C. quindiusense was used for making candles, but later was replaced with artificial wax or by the arrival of electricity. Everything you could ever want to know about the genus can be found in Phytotaxa 34, A Revision of the Andean Wax Palms, Ceroxylon (Arecaceae) by Maria Jose Santin and Gloria Galeano. The genus is of particular interest to me because specimens dotted the landscape in Peru when I visited in the early 1970’s and I guess I wasn’t expecting to see tall palms in the Andean foothills.

Cupressus macrocarpa

Cupresuss macrocarpa

The tour participants were lucky to visit the only two locations where the native Cupressus macrocarpa (“Monterey cypress”) are located – at the Point Lobos State Reserve and at the Del Monte Forest. I have been to both and it is difficult to imagine such a limited distribution when once it was more widespread. Their habitat is now defined by cool, moist summers and the ever-present sea fog; but they also grow well in western Oregon – I have some cultivars – although they are hardy to only about 10F. These days Cupressus macrocarpa is known by the cognoscenti as Hesperocyparis macrocarpa...but for commercial reasons, and out of laziness, this old nurseryman is slow to change (and the Hillier Manual also).

Hesperocyparis macrocarpa 'Goldcrest'

Hesperocyparis macrocarpa 'Greenstead Magnificent'

Hesperocyparis macrocarpa 'Wilma'

The new genus Hesperocyparis is supposedly based on genetic evidence that the New World Cupressus are not very closely related to the Old World Cupressus species, at least so say Adams, Bartel and Price (2009) in A new genus, Hesperocyparis, for the Cupressus of the Western Hemisphere in Phytologia 91 160-185. Anyway I grow 'Goldcrest' which is narrowly columnar and which features ascending golden branches with a pleasant aroma; and I have grown the popular cultivar 'Wilma', a juvenile form of 'Goldcrest' which can be found in florist shops and boutique emporiums,* but which for me always reverts back to the 'Goldcrest' foliage. I have had great success with the selection 'Greenstead Magnificent' which presents good blue foliage; and besides, Buchholz Nursery decided that the normally flat-growing dwarf would be better offered as a staked, upright tree, and our unique constructs easily sell out every year.

*Twenty years ago I was surprised/impressed to find 'Wilma' for sale in a Tokyo florist's kiosk.

La Jolla Beach

Ficus macrophylla

My wife and children absolutely love the beach at La Jolla, near San Diego, and they can spend most of a day in the water. I've evolved into a landlubber sitting in a beach chair with a cold beer, where the entertainment is observing the bikini-clad fauna of the area. After a couple days of that, however, I grew weary and had my wife drop me off at Balboa Park where I could be alone and visit the art museums, the tropical-plant conservatory, and the less than inspiring Japanese Garden, one of the worst that I've ever seen. In the middle of those attractions is a grass lot with a fenced off tree that had one of the widest canopies that I've ever seen, and thankfully the above sign identified the tree because I would never have known. Ficus macrophylla is not listed in The Hillier Manual, presumably because it is not hardy in Britain. It is a large evergreen tree in the Moraceae family native to eastern Australia, and the common name is due to one location at Moreton Bay in southern Queensland, Australia. Ficus macrophylla is a “strangler fig,” meaning that seeds germinate in the canopy of a host tree and they live as epiphytes until the descending roots make contact and grow into the ground. At that point the ungrateful seedling enlarges and eventually strangles its host and stands by itself. Another interesting characteristic is that it has a mutual relationship with fig wasps, where figs are only pollinated by fig wasps, and fig wasps can reproduce only in fig flowers.

John Torrey

Asa Gray

Pinus torreyana

Pinus torreyana

Pinus torreyana

Pinus torreyana witch's broom

Brief mention is given to “the smallest native range of any American pine species” which is Pinus torreyana at two locations north of San Diego. Robischon said that they could not visit Torrey State Park by buss but doesn't explain why as a good road goes up the hill to the visitor center. On my visit a couple of years ago I even spotted a witch's broom mutation en route. The pines are beautiful from a rugged wind-swept point of view, and the species is unusual botanically because it is a “yellow pine” but the needles are presented in fascicles of five, when usually similar pine species have needles bundled in two's or three's. The specific epithet honors John Torrey (1796-1873), an American botanist, and by coincidence the 2019 IDS Yearbook also features “The Tree of the Year” which is the oriental Torreya nucifera. Torrey was perhaps America's most esteemed botanist of his time and his pupil and friend Asa Gray continued his work. In 2017 the Torrey Botanical Society celebrated its 150^th birthday, and is the oldest botanical society in the Americas. By the way, Torrey was a New Yorker and he never did see the rare groves that bear his name, so when I was there I didn't walk in his footsteps. I did walk carefully and stayed on the paths through the chaparral, as a sign alerts you to do so on account of rattlesnakes.

Karl Ludwig von Blume

Eucalyptus deglupta

Eucalyptus deglupta

Back at Balboa Park, the IDS group saw Eucalyptus deglupta – the “Rainbow gum” – and the guide even sprayed water on the trunk to show off the wonderful colors. Somehow I missed it when I was there – maybe I needed a guide with a spray bottle – but I have seen it in other southern California arboreta. I've been tempted to buy seeds of it (which are available on eBay), but what do I do when the fast-growing, non-hardy species hits the top of my greenhouse? The E. deglupta species was first described by Karl Ludwig von Blume (1796-1862), a German-Dutch botanist, and the specific epithet deglupta was chosen from a Latin word meaning “peeled off” or “husked..” It can now be found throughout the world's mild locations and the wood is harvested for pulp – but what a shame to cut one down. Also known as the “Mindanao gum,” it is native to Papua New Guinea, the Philippines and Indonesia and its range actually extends into the northern hemisphere, the only species to do so. Out of about 700 Eucalyptus species, only four do not occur in Australia, and E. deglupta is the only species usually found in rainforests.

Huntington Botanic Garden

Huntington Botanic Garden

Henry Huntington

The Europeans were treated to a visit to the Huntington Botanical Gardens, which throughout the article is misnamed Huntingdon, which certainly would have annoyed the railroad magnate Henry Huntington (1850-1927). In any case, Henry H paid $240,000 for his 600-acre ranch in San Marino (near Los Angeles) in 1903, and the orange marmalade you can buy in the gift shop is made from fruit grown on the ranch. Besides the gardens there is an art gallery containing such works as Blue Boy by Thomas Gainsborough, Pinkie by Thomas Lawrence and a library with treasures such as one of only two known copies of the first published version of Shakespeare's Hamlet. When Henry H. was asked about any plans to write an autobiography, he responded, “This library will tell the story.” A bit more bizarre is that the library holds a lock of Abraham Lincoln's hair which the embalmer cut near the vicinity of the fatal wound. Also, a handwritten note from Lincoln to his bodyguard giving him the night off the evening he was shot.

Huntington Desert Garden

Echinocactus grusonii

Echinocactus grusonii

Puya alpestris

Puya alpestris

The botanic garden contains various individual gardens such as a desert garden, a palm garden, rose, camellia, herb and jungle gardens, as well as Japanese and Chinese gardens. I estimate that it would take at least three full days to see it all, and you would probably want to visit in both spring and autumn. My favorite is the desert garden even though I know very little about the plants therein. I was also impressed with the gardener who was on his hands and knees, gingerly pulling the weeds. The Huntington is surrounded now by a neighborhood of middle-class homes, and I fantasize about living just a couple of blocks away from this national treasure. Is it too late to apply as an intern?

Sequoiadendron giganteum

I'll repeat that I've never been on an IDS tour, and certainly not on this California trip. My blog is not a chronological travelogue, rather just my impression of the plants and places that the lucky Europeans were able to experience, mostly from the southern half of the state. I'll continue next week with a Part 2, where the best trees are yet to come.