The J.C. Raulston Arboretum (JCRA)

Many who know me, or who think they know me, are probably surprised at my expressed infatuation with North Carolina. Why does Old Buchholz, who is so entrenched in west-coast Oregon that he has perpetually soggy boots and lichen growing behind his ears, just what does this old geezer see in a locale three thousand miles away? The answer is that I have never sweltered in their God-awful summers, and for me it is a land blessed with verdant spring landscapes and vibrantly blazing autumnal colours. But besides that, “Carolina is on my mind” primarily because I love the friendly, polite people.

 

For my end-of-October (2022) visit I was accompanied – or rather led – by my wife Haruko, whose purpose was to keep me safe from the Temptress of Carolina, knowing how easily I could fall for her Southern Hospitality. It was Haru's first “on the bus” experience with the quirky individuals that typically join plant-society tours – in this case the International Maple Society – and it was obvious that her exotic presence was most welcome. There was probably some speculation as to why we are coupled together at all, a question that I frequently wonder myself. The common denominator for the gathering was our collective goofiness with all things maple, and besides the wonderful, personal friendships that developed, we all learned a lot more about our beloved Acer genus.

 

The best part about the International Maple Symposium (2022) was our visits to various gardens and arboreta. Last week the Flora Wonder Blog detailed our experience at the Sarah P. Duke Gardens in Durham, NC, while the following day featured a (return for me) tour of the J.C. Raulston Arboretum in Raleigh. What began as a rather humble undertaking, through hard work and perseverance, the JCRA has developed into one of America's outstanding botanical institutions. Wow! – if I could be in my 20s again I would certainly apply for an internship. Haruko was enthusiastically impressed with the garden's entrance and its lively water feature, so much so that she hurried to the nearest convenience store to purchase a lottery ticket...so that she could win millions and design a water paradise herself (but that's just my fantasy).

 

Cornus wilsoniana

Entering into the garden I soon encountered a creamy, tan-trunked tree, one I initially assumed to be a specimen of the South's ubiquitous Crepe myrtle. But no, it was Cornus wilsoniana, a tree that The Hillier Manual of Trees and Shrubs (2019) describes as “A small, deciduous or semi-evergreen tree with ornamental or peeling piebald bark not unlike that of Pinus bungeana, especially in warm sunny sites and climates.” That description reveals, I think, a taxon probably only mildly hardy for western Oregon, but out of my admiration for the great English plant explorer E.H. Wilson, I feel compelled to attempt to grow the tree that bears his name, and I know where to purchase seedlings (Heritage Seedlings, Oregon). Hillier justifies my interest by describing: “The marbled flaking bark on established trees can be spectacular.”

 

White Jade

At the JCRA the Cornus wilsoniana species was further glorified by a cultivar designated 'White Jade' which displayed especially showy bark, but a feature that could be a result of cultural factors rather than something clonally specific. For what it's worth, Bliss-Ninny types admire the gemstone white jade for its power to make one feel calm and peaceful...blah blah...with the ability to purify the energies of the heart and enhance this, that and the other. We could all use such enhancement, right?

 

Daphniphyllum teijsmannii 'Mountain Dove'

I was surprised to find a variegated Daphniphyllum in the JCRA collection and the D. teijsmannii specimen looked good in spite of Raleigh's brutal summer heat. I was further intrigued with the cultivar name of 'Mountain Dove', and whether that was an American appellation or perhaps an English translation from the original Japanese name. I acquired the variegated shrub about 15 years ago when I was gifted it by a former Japanese intern who brought it during a subsequent visit, with the attached (invalid) name of 'Variegata'. It didn't really matter what it was called as our propagation efforts were unsuccessful, via rooted cuttings in summer that is, and I never attempted to graft because I didn't have the same species for rootstock. To complicate matters, Hillier doesn't even list the species teijsmannii (sometimes spelled teysmannii). The genus is in the Daphniphyllaceae family and is native to Japan and Taiwan, known by the common name in Japan of hime yuzuriha. My two starts from my intern were both grafts, one of which I sold a few years ago, and the remaining one I should probably plant out in the garden. Then do I use the cultivar name of 'Mountain Dove'?

 

Daphniphyllum teijsmannii 'Mountain Dove'

Johannes Elisa Teijsmann

According to the IDS (International Dendrology Society), the original spelling of the specific epithet is teysmannii, and it is the Dutch who are responsible for the misspelling, but then the epithet commemorates the Dutch botanist Johannes Teijsmann (1809-1882). In short, I gained no further knowledge after seeing this plant at JCRA; and then the next day a different-looking variegated specimen at Plant Delights Nursery, also labelled 'Mountain Dove', threw me into further confusion. I concur with Grimshaw/Bayton in New Trees (Kew Publishing) 2008: “The taxonomy and classification of Daphniphyllum is best (or more politely) described as a terrible mess, epithets having seemingly been combined almost at random by different 'authorities'.” If the Flora Wonder Blog was ever a two-way street, with a forum where I can also learn from you, then now is the time to set me straight.

 

Acer oblongum

Acer oblongum

Arboreta such as JCRA seem compelled to collect BIO (Botanical Interest Only) maples, those species that are often only marginally hardy, and which have little if any commercial appeal. In fact, the more obscure they are, the better they seem to belong in their collections. One such is Acer oblongum, a maple in the Pentaphylla section from the eastern Himalayan foothills and southern China. I have probably seen it in the wild but I couldn't identify it at the time, and without JCRA's label I wouldn't have had a clue about its identity. Acer oblongum was introduced to Europe from the Himalayas (in 1824 by Nathaniel Wallich) and later from China by E.H. Wilson in 1901. Its specific epithet oblongum refers to the oblong leaf shape, while its common name of “Flying moth tree” is not obvious to me, except unless it's referring to the moth-shaped samaras as they flutter in a breeze?

Acer leucoderme 'Confederate Ghost'

Acer leucoderme 'Confederate Ghost'

Another obscure maple at JCRA was labelled Acer leucoderme 'Confederate Ghost', but Hillier alerts us to refer to Acer saccharum subsp. leucoderme as the latest classification, in other words to a southeastern USA form of “Sugar maple” with the common name of “Chalk maple,” a species described as “A small tree...with lovely autumn tints.” The leucoderme name (“white skin”) was given on account of the smooth, light gray trunks on mature trees, and first recognized as distinct from northern Sugar maples by John Kunkel Small in 1895. I knew of no cultivars of the “Chalk maple” until I discovered the 'Confederate Ghost' with its cream-white leaves with prominent darker-green veins, known as reticulation in horticulture. It would be interesting to trial it in full sun, partial shade and in deep shade to see how it fares in Oregon with various light amounts. As you can see from the photos above, ‘Confederate Ghost’ doesn’t present any ornamental interest at the end of October in North Carolina.

Acer serrulatum

Acer serrulatum

Yet another seldom-encountered species of maple in horticulture is Acer serrulatum, a description for which cannot be found in DeBeaulieu's An Illustrated Guide to Maples or in The Hillier Manual of Trees and Shrubs. So, another obscure Asian species that doesn't fit neatly or consensusly into botanists' classification schemes. However, it is considered closely related to Acer oliverianum, or as Acer oliverianum subsp. formosanum. If the latter is so, then it is a vigorous maple with olive-green bark, fast-growing and attains a large size in its native Taiwan (old name = Formosa). In any case one can graft A. serrulatum (in the Palmata Section) onto the readily available Acer palmatum, but generally commercially-run nurseries do not want to compromise possible maple hybrids or rootstocks with less hardy parentage. I suppose the main ornamental feature for A. serrulatum is when the glossy green leaves of summer turn to purple, or at least to bright red and yellow in the autumn, and that the new growth in spring is also a glossy chocolate-purple. Darn that it's not more winter hardy, for it's another example of a Chinese “Japanese” maple that would be far more popular if its classification was more certain, and if it was able to tolerate the same cold-hardiness limitations of Acer palmatum. The specific epithet serrulatum is of Latin origin, from serrula meaning “little saw” due to jagged leaf edges, but that's not a characteristic so noticeable to have warranted a specific epithet (if you ask me).

Senna corymbosa

Senna corymbosa

A pretty shrub in the back corner of the arboretum was Senna corymbosa, the “Buttercup bush” from Argentina, and even at the end of October a few yellow flowers were still present. Senna is a large genus of flowering plants in the legume family (Fabaceae, and subfamily Caesalpinioideae), and the genus name is derived from Arabic sana which described plants whose leaves and pods have cathartic and laxative uses, and interestingly another common name is “sensitive plant.” One value for me of arboreta such as the JCRA is that we share about the same frost-hardy concerns, so when I see a South American plant thrive in North Carolina, it gives me hope that I can add it to my Flora Wonder Arboretum in Oregon. Of course, if it perishes in winter at JCRA everyone there still keeps their job, while Mr. Buchholz could go homeless if he invests too heavily in unknown-hardiness Argentinean buttercup bushes.

Alnus formosana

Carpinus fangiana

Betula medwediewii

Carpinus is in the Betulaceae family, which is not surprising when one examines the Carpinus and Betula genera, because, well, they look about the same. The Carpinus genus (aka “hornbeams”) consist of 40-or-so species found mainly in China, but also in the Americas, even as far south as Central America (for example: C. caroliniana). One of my favorite species is C. japonica which Hillier describes as “A very beautiful...small tree or large shrub with prominently corrugated leaves and conspicuous fruiting catkins. In general appearance recalls Alnus firma from Japan.” There's a passel of leafy trees that look somewhat similar – Carpinus, Betula and Alnus (alder) – that look close enough to confound first-year horticulture students and also yours truly. Of course, if you look at them sexually, as in their fruiting structures, they are clearly (individually) distinct. I have dabbled in the three genera commercially, but none of them ever figured prominently in the success of my company. Most of you would describe me as “the maple guy,” and indeed I am a member of the International Maple Society, but I don't really know much about hornbeams, birches and alders, nor will my career ever be broad enough to incorporate any expertise. Is there also a Birch society, an Alder society and a Hornbeam society? Even if so, I probably won't be attending their international conferences.

Carpinus japonica 'Silver Lace'

Carpinus japonica 'Silver Lace'

Nevertheless – the above caveat aside – I was surprised and pleased to encounter at JCRA a Carpinus japonica 'Silver Lace', and even with its somewhat bedraggled, end-of-summer appearance, I was fascinated with the green leaves edged in silver. No fall color was yet evident, but I suppose it would turn to yellow in most climates; also I detected no autumn fruits...unless the JCRA staff had already harvested them. Its fine and delicate texture is what attracted me, and I will seek one out to add to my collection in Oregon. I didn't know that C.j. 'Silver Lace' existed at all until my visit to JCRA, but now I learn that it has been commercially available at some of my customers' nurseries, so I will search for one. I love the description from Oregon's Dancing Oaks Nursery: “A rare and handsome tree with ornamental deciduous leaves that have very fine eyelash-like teeth on the leaf margins. The fruiting bodies that appear in late spring are showy, papery drooping clusters* that are rosy pink.”

*“Very fine eyelash-like teeth, papery drooping clusters etc.” Horticulturalists and gardeners such as you and me are blessed with stimulation we receive from the plants themselves, but also we appreciate the literature of horticulture, for the words define our basic desire to connect with the leaves, trunks and twigs that surround us. “Eyelash leaves” indeed!

 

Tsuga oblongisquamata

An uninteresting-looking hemlock at JCRA had a label that read Tsuga oblongisquamata. That was a completely new name for me, and I felt instantly stupid, or at least totally out of the horticultural loop. I examined the foliage and the needles resembled most Tsuga, such as T. canadensis and T. heterophylla, i.e. no more “oblong” than those species. And “squamata” usually refers to flaking bark, but their specimen, though young, wasn't displaying that characteristic, so why was I encountering a new species (for me) that I've never heard of before? When I returned home I researched my find and discovered that it is also known as Tsuga chinensis var. oblongisquamata, and in fact there are quite a number of varietal forms of Tsuga chinensis. That's not surprising I guess, but clearly the Chinese botanists Cheng and Fu are splitters, and they're apparently authorized to divide/split the species as much as they want.

Cephalotaxus wilsoniana

The Chinese Cephalotaxus wilsoniana is another conifer that honors E.H. Wilson, although some botanists consider the “species” to be merely one of the varieties of C. harringtonia (from Japan and Korea). The specimen at JCRA is not particularly attractive, but at least it is hardy enough to withstand North Carolina winters. The redeeming value for me is when mature specimens are limbed up to reveal reddish-brown peeling bark, and also that it is well-suited as greenery to grow in shade. It is a species in the yew family (Taxaceae) and is commonly called the “Taiwan Plum yew” due to olive-like fruits which ripen in the second year. As with Cephalotaxus harringtonia it is also commonly known as the “Cow’s-tail yew.” Sadly it is hardy to only about USDA zone 8 or 10 F, therefore sales were always weak for me.

Cupressus funebris

Cupressus funebris

Cupressus funebris is known as the “Chinese Weeping cypress,” or “Mourning cypress,” and certainly it seems that it could brood at peace in a gloomy, winter’s cemetery. I was fortunate to see large specimens (said to be 800 years old) near Kunming, Yunnan near the Black Dragon Temple, which was already a Chinese tourist’s destination back in the 1980s. I’m not certain though if these were naturally occurring trees or if they had been planted centuries ago. I used to grow a modest number that were propagated by grafting onto Cupressus glabra or Juniperus scopulorum rootstock, but in all cases the tops would grow too fast in my nursery’s conditions and they would flop sideways with the slightest wind. Besides its appropriate use – at least in the past – as coffin wood,* since it is durable and close-grained, the foliage is considered antiperiodic and can aid in excessive menstrual flow, a condition that is very foreign to me. But the grafters of conifers, the nurserymen who actually handle and slice the twigs (such as I used to), we can attest to the pleasant aroma of the wood, and the oil has been used in perfume. As with the aforementioned Cephalotaxus wilsoniana, the Mourning cypress is only hardy to USDA zone 8 (10 F), and all of my outside trees perished in a cold winter 30 years ago, and I’ve never grown it since…which is why I was happy, but surprised, to see it thriving in N. Carolina.

*The origin of the specific epithet funebris is derived from Latin funesris, from funus for “dead body.” Hence our term today for “funeral.”

Pteroceltis tatarinowii

Ptera* is a prefix one encounters occasionally in botany which is from Greek pteron meaning “wing” or “feather,” and I know of the plants Pterostyrax (in the Styracaceae family) and Pterocarya (in the Juglandaceae – walnut – family). Before my visit to JCRA I didn’t know anything about a Pteroceltis genus, but their P. tatarinowii is also known as “Tara Wingceltis.” Its range is now restricted to China and Mongolia (hence tatarinowii) but the fossil history records it previously present in Europe and the United States. Pteroceltis is in the Cannabaceae family, and members of the latter group include Cannabis (hemp), Humulus (hops) and Celtis (hackberries). Even though they share the same evolutionary origin, some are herbaceous plants like Cannabis, and others are trees like Celtis. The bark of the Celtis genus won’t get you high, I suppose, but it has been used to produce Chinese rice paper. Celtis is a medium-sized deciduous tree that I have never grown, but C. occidentalis is native to central and northeastern USA, and is damn-hardy enough to survive to USDA zone 2 (-50 F).

*Many children know of the dinosaur Pterodactylus (winged finger), the iconic heron-looking flying reptile which is probably only second to T-Rex in their – the children’s – knowledge and imagination about prehistoric life. Ok, you can also include the Flintstones.

Air Bee & Bee

On a lighter note I was impressed with the arboretum’s Bee Hotel which they dub the Air Bee & Bee. The signage was simple and adequate for the general public, and I suppose that visiting children are all impressed and come away with a few factoids* about the value of bees; after all bees are considered the “Angels of Agriculture” and we would all be much hungrier without them. Of the world’s 20,000+ species of bees the “Honeybees” (Apis mellifera) are the most important pollinators of agricultural crops, and are required for about one-third of all the food that Americans eat.

*For example, bees visit thousands of flowers in order to make one teaspoon of honey. Also, the arboretum boasts that North Carolina has the most beekeepers per capita in the USA. Busy, bee busy!

J.C. Raulston

James Chester (J.C.) Raulston supplied the driving energy to establish a tree collection – an arboretum – in Raleigh, North Carolina. Mr. J.C. was indeed an intensive bundle of energy, and I was privileged to host him on his two visits to Buchholz Nursery and the Flora Wonder Arboretum…or, or did he visit just one time – it was about 25 years ago so I can’t remember for certain. I found J.C. to be rather comical actually – and I say that with no disrespect – but when he visited my Oregon location he quickly shook my hand…and before I could reply with “nice to meet you” he dashed off to inspect a nearby tree and process its labeled identification. I attempted to keep up with him to be a good host, and to perhaps learn something besides, but then he had already sprinted to another plant, and then another…so that finally I just stood in the middle of the Buchholz Nursery’s original Display Garden while he dashed into its various corners, then he would buzz back to me with a question or an opinion. After about 30 minutes of his whirlwind adventure he and/or his handlers announced that, regrettably, they were behind “schedule” and were late for their next appointment, so they hurried off to their running car. I wasn’t miffed or jealous, and I felt no disrespect even though I had set aside the whole day to entertain the Carolina plant guru. It took me the remainder of the day, though, to recover from his frenetic whooshing in and out.

I thought it was impossible that the man “with chlorophyll in his veins” could be terminated just a year later (in 1996, at age 56) in an automobile accident. I’m sure that a lot of people felt as I did, that we were short-changed with his demise, that our relationship had just begun and why did he have to go away so soon?

My recent visit to the JCRA was botanically and horticulturally entertaining, and I gained some more knowledge about tree stuff for sure, but I left with a bittersweet regret from the experience…pining that I should get just a few moments with J.C. in his garden.