One of the newest discovered species of our native asarum (formerly Hexastylis) is Asarum finzelii, from northeastern Alabama. In foliage, the plant resembles both Asarum arifolium and Asarum speciosum. The flowers, however, are quite different from both, as you can see below. It is our hope to get this propagated before too long, so we can work to make it more widely available.
Tag Archives: taxonomists
Much ado about Memminger’s Heartleaf Wild Ginger
This spring, we flowered the highly confused NC native wild ginger, mistakenly known as Asarum memmingeri in the garden. In reality, it’s never been given a proper name, so we refer to it as Asarum sp. nov. Allegheny Wild Ginger. Below, Patrick explains how this ginger was dropped into a botanical abyss, and what needs to be done to return it to proper recognition, and to correct a cascade of past taxonomic errors. -ta
When I was a boy the tiny-flowered evergreen wild gingers that grew all over our land in Alleghany County, North Carolina seemed like they must be a common species, and should have a name. As a boy of 12, however, I had a hard time placing a name on them since they didn’t seem to fit the photographs in popular wildflower books or match the plants that my grandmother’s flora called Hexastylis virgnica (now Asarum virginicum).
I became obsessed with heartleafs as a child and the curiosity remains strong. When I entered college I was lucky enough to take Dr. Peet’s Ecological Plant Geography class at the University of North Carolina, Chapel Hill. Our class, which was all graduate students and me (as a sophomore), was expected to do a project detailing and explaining the range of a particular genus or family of plants. I chose the smooth-leaved evergreen Asarum, then known then as Hexastylis.
I spent the spring semester travelling to every corner of the American South seeking species I didn’t know and trying to fill in the vacant counties in the range maps of those species that I did know. I took countless measurements of calyces and made copious notes on habitat. I was shocked when I travelled to southeastern Virginia to visit the area where Asarum virginicum was likely first collected. These true Asarum virginicum plants were nothing like the “A. virginicum” I was so used to seeing in my boyhood home.
A quick trip to the Earl Core Herbarium at West Virginia University, and later to the Smithsonian, brought to light a serious problem with what botanical taxonomists currently refer to as Asarum virginicum and an even larger problem with what we call Asarum (Hexastylis) rhombiformis and Asarum (Hexastylis) memmingeri.
It seemed as if the Alleghany County plants I had called Asarum virginicum as a child had been mistakenly identified by WVU taxonomist Earl Core as Asarum memmingeri. Complicating this further was that the probable original type specimen for A. memmingeri would later be published under a new name, H. rhombiformis!
To make sense of the cascade of errors, we need to go back further in time. This story begins in 1897 with W.W. Ashe’s publication of The glabrous-leaved species of Asarum of the southern United States in the Journal of the Elisha Mitchell Scientific Society. Here, Ashe describes for the first time Memminger’s Heartleaf (A. memmingeri). From the description it is obvious that he is describing a plant with a very small flower with a very narrow opening (7 mm wide or less).
Error #1 occurred when Ashe described the original type locality as Mitchell County, based on a collection by E.R. Memminger. When I was looking for a type specimen, the best option I could find was a specimen collected (in duplicate) by E.R. Memminger himself that he says in his own handwriting represents the type location. During Ashe’s time, it was not required to designate a type specimen, but the problem was that Ashe’s citation of Memminger’s specimen was actually from Henderson County (“Tranquility”, Flat Rock, NC), not Mitchell County.
Type specimen of Asarum memmingeri collected by E.R. Memminger
Error #2 occurred as we fast-forward to 1987, ninety years after Ashe published his work, when L.L. Gaddy described a new species of Hexastylis that occurs in Southwestern NC and Northwestern SC as H. rhombiformis (Asarum rhombiformis (combination not yet made). In this description he cites E.R. Memminger’s specimen from Henderson County, which, is actually the type specimen of Asarum memmingeri as representing his new species H. rhombiformis. Consequently, the name H. rhombiformis is invalid and this plant should be known as A. memmingeri.
Error #3 occurred when J.K. Small of the New York Botanical Garden, Earl Core of West Virginia University and others annotated (attributed) numerous Asarum collections from West Virginia, Virginia, and NC, of an un-named species that they mistakenly identified as A. memmingeri. Blomquist and all modern authors have since combined these tiny-flowered plants with small openings to the calyx tube within a “catch-all” concept of A. virginicum. Other taxonomists since have followed their mistaken identification of A. memmingeri or A. virginicum for these plants that are known to range from WV south to NC.
We know that these plants that J.K. Small, Earl Core, and others called A. memmingeri actually represent the heartleaf from my Alleghany County childhood homestead and surrounding regions that still has no accepted name.
It is time to clear up the confusion and formally describe these plants along with a new, correct scientific name. For our purposes we will refer to them here as Allegheny heartleaf for a common name (in reference to the mountains, which have a different spelling than the NC county, rather than Alleghany County, NC).
In vegetative form, the Allegheny heartleaf is similar to most of its relatives including A. virginicum, minus, heterophylla, and naniflora. They are tightly clumping with leaves that tend to be as wide or wider than long with a broad cordate base. Though I have found populations with some mottling on the leaves, they tend to lack any variegation altogether.
The flowers on the undescribed Alleghany County heartleaf are much smaller in all dimensions and also differ in the tube constriction from both A. virginicum and true A. memmingeri.
The Allegheny heartleaf is found in typical heartleaf habitat: highly acidic, organic duff beneath oaks and pines and often in association with Rhododendron and Kalmia. They are found along the margins of Southern Appalachian fens and small stream swamps as well as along stream banks and on steep rocky slopes and bluffs that are most often north or east-facing.
The natural range of the species seems to be from Watauga/Avery counties North Carolina, north through West Virginia at low to moderate elevations. In North Carolina nearly all populations are located along the New River drainage, though there are outliers along the Yadkin River drainage downstream to Donaha Bluffs in Forsyth County. This taxa is tightly tied to the Appalachian range with outliers into the piedmont in areas with cool microclimates along rivers that originate in the mountains. Between the mountain populations of Allegheny Heartleaf and the coastal Virginia Heartleaf (Asarum virginicum) occurs A. minus, which largely replaces Allegheny Heartleaf in most of the piedmont of North Carolina.
Allegheny Heartleaf was very difficult for me to grow, even in seemingly hospitable microclimates in Clemson, South Carolina. It seemed to survive but only for a short time, gradually declining and producing dwarfed leaves by the 2nd season and then disappearing by the 3rd. I am extremely pleased to have this species growing strong, flowering and producing normal sized leaves for its second season here at Juniper Level Botanic Gardens.
What needs to happen is for Hexastylis rhombiformis to have a name correction to Asarum memmingeri, and for the plant widely known as Asarum memmingeri to finally be named for the first time, hopefully with a specific epithet named for the Allegheny Mountains, which incorporate the heart of its range.
Pinus in the Garden: Smaller is better
Here are a couple of dwarf pines in garden that are looking particularly great in mid-winter.
The first is PInus strobus ‘Mini Twists’ is a dwarf seed-grown selection of our native white pine that matures at 6′ tall x 4′ wide. This is a 2005 introduction from Vermont conifer specialist, Greg Williams. Good drainage is a key to success with white pines in our hot, humid climate. Hardiness is Zone 3a-8a.
Below is Pinus thunbergii ‘Thunderhead’, a 1987 introduction of a selected seedling of Japanese black pine from Angelica Nurseries of Maryland. In 10 years, it reportedly will reach 15′ in height x 20′ in width. Although it’s known commercially as Pinus ‘Thunderhead’, that cultivar name was actually used six years prior for a different pine, and according to International nomenclatural rules, can only be used once per genus, so the correct name would become Pinus ‘Angelica’s Thunderhead’. Hardiness is Zone 6a-8b.
Another Plantsman Bites the Dust
We just discovered that one of our good plant friends, plantsman and former mail order nurseryman, Dick Weaver, 77, passed away early in the days of the pandemic in June 2020.
Dick and I had been corresponding regularly, but in a final note in late 2019, he indicated that Parkinson’s had now made it difficult for him to type emails. Although we chatted on the phone after that, I completely lost track of him during the COVID craziness. It was only when I tried to catch up last week that I discovered he’d passed not long after our last chat.
Dick and his life partner, Rene Duval, started We-Du nursery in Marion, NC in 1983, after Dick left his job as Assistant Curator/Taxonomist/Plant Explorer at Boston’s Arnold Arboretum (1970-1983). Armed with a PhD in Botany from Duke University, Dick gave up a good salary and stable job for the uncertain, crazy world as a mail order nursery owner.
As a young nursery owner, We-Du Nursery near Marion, NC was always one of my favorite stops to see and acquire new plants and chat with other plant nerds. Their nursery specialty was both North American native and their Asian counterparts–similar interests to ours.
After 13 years in the mail order business, Dick and Rene sold We-Du to move to Puerto Rico to run a coffee plantation. Dick thought mail order was difficult until he tried to run a farm in the mountains of Puerto Rico. In 2001, I remember a desperate sounding email from Dick, saying they needed to move back to the US asap…preferably to Florida. We made a few calls, and connected Dick to friends in the Gainesville area, which eventually led to Dick getting a position with the Florida Department of Agriculture in 2002. He worked there until his retirement in 2010.
It was great to have Dick and Rene back on the mainland and to once again be able to visit in person, this time at the fascinating home and garden they created in North Florida.
In 2016, after Rene passed away, Dick moved to Pennsylvania to be near his remaining family, starting yet another garden. Sadly, we never got to visit his final home. We’ll miss the plant chats and plant exchanges, but thanks for adding so much to the world of horticulture!
Few gardeners outside of California and the Pacific Northwest have tried growing Cupressus sargentiae (Sargent’s Cypress). We often assume that plants endemic to California won’t grow on the East Coast, but our trials have found such a broad assumption to be quite false. Our specimen from Patrick’s collection north of San Francisco still looks great after our recent 11F temperatures. The amazing lemon-scented foliage fragrance is quite incredible, and as such, should make it a great plant for making holiday arrangements/wreaths. The plant should mature size should be between 40-70′ in height. Taxonomy of this Cupressus is stuck in a taxonomic tug of war, with one camp, who wants to rename it Hesperocyparis sargentii. Winter hardiness is Zone 7b-10, guessing.
Dry-opteris on a Wet, Rainy Day – New Relevations
The cold and raw weather of late autumn and winter provide the perfect opportunity to sit down with the dissecting scope and put our ferns through the identification mill. Often gardens and nurseries receive a plant into their collections from an exporter or collector who has put their best guess on the identification. After many years in cultivation, we realize what we thought was the right species name for our specimens is incorrect. Today’s nasty weather provided the opportunity to examine, in detail, one of our favorite evergreen fern groups – Dryopteris section Variae.
These firm-leaved evergreens produce thick-textured, durable, medium-sized fronds of varying shape but all display a noticeably longer basioscopic pinnule (that’s fancy talk for the lowest, innermost segments of the divided leaves). All members of the section that we have grown have proven to be very adaptable to our hot, humid summers and unpredictable winters if grown in shade or partial shade in moist woodland garden conditions. The fronds tend to burn if they receive too much light. They are late risers in the spring often not producing a new flush of leaves until late spring or even early summer.
At the beginning of the day, we started with 8 accessions of Dryopteris varia, 2 accessions of Dryopteris bissetiana, 6 accessions of Dryopteris formosana, one accession of Dryopteris saxifraga and a couple of unknowns. From these numbers you would expect that the one plant we would know best would be Dryopteris varia.
Well…it turns out all the plants we had received or had identified as D. varia were actually representative of other taxa. If you’ve never tried keying ferns using The Flora of China or The Ferns and Fern Allies of Taiwan, you would have no idea just how difficult a process this is. The floras of these areas are notoriously difficult to use and often contradictory or difficult to assess using illustrations or pictures (yes even plant taxonomists google names to find images). Very quickly we became intimately familiar with the nature of the stipe and rachis scales, frond outlines, and disposition of the vestiture (yeah you think that sounds easy, right?).
We found most of our collection was actually composed of Dryopteris bissetiana, which are mostly from collectors who sent us tentatively identified wild-collected material. The majority of these were from Sichuan in China, however one very beautiful, deep green and glossy selection that is only half the size or less of the others was Tony’s collection in Korea, and has tentatively been identified as Dryopteris saxifraga. All of these are remarkable garden plants, but we are very excited to some day offer the choice dwarf from Korea which we have named ‘Cheju Dwarf.’
It was a pleasant surprise to find that our collections of Dryopteris formosana were correctly labelled, but we weren’t prepared for there to be two distinctly different looking plants represented in our garden that are the same species.
One of these is the plant that has been shared among fern enthusiasts for some time that is the typical sexually reproducing diploid. The other is an apogamous triploid that looks like a completely different species. In a diploid (like you and I) the pairs of chromosomes uncouple and one copy of each goes into making the male and female gametes.
Thus, each gamete has only one set of each chromosome (haploid) and when combined with those from the complementing sperm or egg results in another diploid. Plants sometimes have a mistake in their cells that lead to the production of gametes with twice as many chromosomes as they would normally have and when such tetraploid plants breed with a diploid the result is a gamete with 2 copies of each chromosome combining with a gamete with only one—thus triploid. In your average plant this triploid is a dead end for reproduction by seed or spore because they have an uneven base number 3—which can’t be divided into an equal number of chromosomes, so it is sterile.
This triploid avoids the curse of having an uneven number of chromosome pairs by avoiding sexual reproduction and producing spores that will result in new plants without the traditional interplay of sperm and egg on a germinated gametophyte (yes apogamy in ferns is still legal in all states and countries). We were puzzled when two very different looking ferns keyed to the same species. Everything that was in the key matched. The bullate hairs, the shape, the color, the basioscopic pinnae and the overall shape.
Our taxonomist, Zac Hill, very quickly uncovered a recent paper by Kiyotaka Hori, et al (2017) which explained and beautifully illustrated our conundrum. The triploid produces a wider, far more pentagonal frond with a less erect nature in the way the blade is held, and a deeper green, highly pleasing color—now that’s pretty darn cool! This new discovery we have named ‘Yushan 2 X 4.’ A new plant for us all to grow in the years to come and now you know why we chose the name diploid (2) X tetraploid (4).
Now that we realize we grow seven different forms of Dryopteris bisettiana, each collection will be given a cultivar name, which will refer back to their specific origin and uniqueness.
Every day brings discovery when you manage a collection of 30,000 taxa but one thing we know for sure, these are amazing, well-behaved, slow growing woodland plants that are the essence of what makes Juniper Level Botanic Garden so amazing.
Patrick McMillan, director of horticulture and gardens
Hori, Kiyotaka, L. Kuo, W. Chiou, A. Ebihara and N. Murakami. 2017. Geographical distribution of sexual and apogamous types of Dryopteris formosana and Dryopteris varia (Dryopteridaceae) in Taiwan. Acta Phytotax. Geobot. 68 (1): 23-32.
You’re so Vein…Anastomosing, that is
Nurses and plant taxonomists are among the few fields in which you would run into the term, anastomosing veins. Having been in the plant world all my life, I had never even run into the term until trying to key our some bamboo ferns in the genus, Coniogramme, almost a decade ago. It turns out that to distinguish between species, you need to determine if the spore patterns on the back of the leaf have an anastomosing or parallel vein pattern. Anastomosing veins are those which diverge and reconnect forming a pattern like a snake skin. We’ve grown quite a few ferns, but none have the amazing vein patterns of coniogramme. Below are the leaf backs of Coniogramme japonica in fall.
A new hardy yellow-flowered Begonia from Arunachal Pradesh
History is replete with examples of new plant species that are first encountered by intrepid plant explorers, yet described later by taxonomists. Salvia darcyi was discovered and introduced into cultivation by Carl Schoenfeld and John Fairey of Yucca Do Nursery. Three years later, they guided researchers to the site who subsequently described the species without acknowledging the original collector. It is unfortunate that the act of discovery by those in horticultural circles are so seldomly recognized (not to mention the indigenous peoples who have known many of them for eons).
Upon my first visit to Heronswood in the autumn of 2019 I was shown a splendid robust Begonia with heavily lobed leaves, short upright stems, and amazing tight-clumping habit with yellow (yes yellow!) flowers. I immediately confirmed that this was a heretofore undescribed species. The plants had been grown from the seed collection made by Dan Hinkley along with fellow collectors and nurseryman, Shayne Chandler and Leonard Foltz, from Arunachal Pradesh India. These plants were shared by Mr. Hinkley with Monrovia who immediately released it under the name TectonicTM Eruption Begonia (Begonia sp. DJH18072).
The unknown Begonia has now been given a formal scientific name Begonia lorentzonii by Swedish taxonomist Eric Wahsteen and the Indian researcher Dipankar Borah, based on two specimens collected by Borah in November of 2018 (incidentally, after Dan Hinkley’s collection). No mention of the plant in cultivation or the contribution of Dan is found in the publication despite the fact that quite a few of the Begonia aficionado crowd around the globe had by then become familiar with the plant. Regardless of the name, this species is among the most spectacular hardy garden plants for cool but not cold climates.
Begonia lorentzonii has proven hardy at Heronswood (zone 8a) where it was left outside with only a covering of leaves and straw in temperatures ranging into the low teens and at least a week long stretch of consistently below freezing temperatures which resulted in ground freeze. It forms 2-2.5’ tall dense clumps with one of the best forms I’ve seen in a cold hardy species.
In late summer through late autumn it is adorned with yellow flowers beset with hairlike projections on the outer surface of the tepals produced on stems that equal or are slightly shorter than the leaves. Begonia lovers should visit the Renaissance Garden at Heronswood to see mature plants in their full glory and a pilgrimage to Heronswood is a must for all hardy Begonia lovers as the collection of rare and unusual cold hardy species is probably the best among our public gardens. While this startling plant appears to be perfectly adapted to life in the mild Pacific Northwest it remains to be seen what its tolerance for heat will be. It was an honor and pleasure to grow and nurture these plants during my time at Heronswood and I must admit my heart and mind will forever be drawn to that sacred space of ground whenever I glimpse a Begonia of any species.
Dr. Patrick McMillan
Willow the Wisp
Carex ‘Willow the Wisp’ is one of Zac Hill’s amazing collections from nearby Willow Springs, NC. This is a widespread native, naturally ranging from Michigan south to Florida and west to Texas. We love the appearance of a head of green hair…minus the head. In the wild, this selection of Carex leptalea var. harperi thrives in wet mucky swamps, like the story of Will-o’-the Wisp. We planted this in similar conditions in a seep at JLBG, where it has made this stunning specimen. Any plant that looks this good in October is undoubtedly destined for a future catalog.
Low Country Treasure Hunt
Last week, Patrick, Zac, and I spent a couple of day botanizing in the low country…i.e. Coastal South Carolina. In between swatting away the incredible troupe of mosquitos which chose to join us, we were able to capture a few images to share below.
The ancient lime sinks are fascinating. Here, old sinkholes due to subsurface limestone rock breakdown have collapsed, forming natural depressions, creating a habitat for our native pond cypress (Taxodium ascendens) and other fascinating wetland species…like alligators. Yes, we did see several, but they were too fast for our camera.
The high water marks are visible on the buttressed trunks of bald cypress.
Much of the region is, or was, a pine/grass habitat. The pines could either be longleaf (Pinus palustris) or slash pine (Pinus serotina) .The dominant grass is known as wiregrass, aka: Aristida beyrechiana.
On the dry sand ridges, we saw these piles of fresh sand adjacent to a nearby tunnel entrance. These are homes to the rare gopher tortoise, which live in the region. Patrick tells me these tortoises will use the same underground lair, which may stretch 40′ long and 10′ deep, for up to 60 years.
Gopher tortoises only emerge from their tunnels when temperatures are between 80 and 90 degree F. Sure enough, we were able to wait and get some images of these amazing creatures.
Another surprise spotting was a bright orange mutant katydid. Our entomologist Bill Reynolds tells me these are crazy rare, and worth well north of $1000 to collectors. Who knew?
Yes, we also saw some cool plants. Asclepias obovata is a little-known milkweed that’s quite rare in South Carolina, so it was great to catch it in flower.
At another site nearby, we caught some late flowering plants of Asclepias tuberosa var. rolfsii.
We visited several patches of amazing pitcher plants, one site with a tremendous variation of Sarracenia flava, which is typically solid yellow. Other sties had three species growing side by side including Sarracenia minor, Sarracenia rubra, and Sarracenia flava. It’s great that such natural area still exist, although they are always in danger from those who sadly dig plants from the wild for sale.
A plant often seen near the pitcher plants is the native orchid, Plantanthera ciliaris.
We were thrilled to find a couple of large patches of the scrub palm, Serenoa repens, from one of the coldest natural populations, which happened to be in full seed. Clonal patches like this are incredibly slow-growing. Researchers in Florida found that such clonal patches are often between 5,000 and 10,000 years old.
It was great to see large drifts of one of our finest native ferns, Thelypteris kunthii, aka: maiden fern. This superb deciduous fern thrives in both sun and shade, tolerating everything from wet to average soil conditions.
A lovely surprise was stumbling on a population of Hamamelis henryi. This coastal species is often listed as a variety of Hamamelis virginiana, but we think it’s probably deserving of species status. Several of the clones we found had lovely dusty blue foliage.
One of the most amazing shrubs was the hawthorn, Crategus munda var. pexa. These ancient specimens topped out at 4-5′ tall, and looked like ancient bonsai specimens.
I’ve long had a penchant for finding gold leaf sweet gums, and this trip added another one to the list. When many woody plants are cut to the ground, they are much more likely to produce mutations as they re-sprout. In my experience, the genus Liquidambar must be the most prone to such mutations.
The fall-flowering Georgia savory, Clinopodium georgianum was in full flower. We’ve grown and offered this for decades, but it was fascinating to see the flower color variation in the wild.
At one stop, we found five different liatris species, including the little-known Liatris elegans.
The native vining legume, Centrosema virginiana, aka: butterfly pea, was in full flower and looking lovely…first cousin to the better known genus, Clitoria.
I’m not a fan of most smilax species, but I was quite smitten by the non-running dwarf Smilax pumila, which grew in the shade like an Asarum (wild ginger). While some clones had green leaves, others had patterns every bit as good as the best Asarum.
On the ride home, we kept ourselves amused unscientifically researching the fastest speed at which leaf-footed bugs could hold onto a car window while copulating. Since our test speed topped out at 65mph, we aren’t sure what it was take to pry these loose, but perhaps someone should research how they are able to hold on so tight, as I’m sure it has numerous industrial applications.
A rosea by any other name would look as sweet
We think Juliet would agree that Cuthbertia rosea is one sweet perennial. Looking great now is the southeast native (Maryland south to Florida) spiderwort, Cuthbertia rosea, which for us, begins its flowering season in spring, and continues sporadically through the summer months. Native primarily to dry sand, this easy-to-grow perennial has exceptional drought tolerance. Like all spiderworts, the flowers open in the morning and close each evening.
This poor plant has long suffered from an identity crises due to dueling taxonomists. This poor plant is also known as Callisia rosea, Tradescantia rosea, Phyodina rosea, and finally Tripograndra rosea. Despite the naming conundrum, it’s surprising that more people don’t grow this amazing plant.