Here's Pyxie!

Pyxie (Pyxidanthera barbulata), near Zuni, Va (3/16/19)

I was able to shout that on a recent weekend in southeast Virginia, but was certainly not the first to do so. That "honor" goes to Bayard Long in 1936.  Long was a botanist most associated with the Philadelphia Botanical Club, collector of approximately 80,000 plant specimens, and long-time friend and associate of Dr. M.L. Fernald (an account of Long's career, and publications, as well as the following image of Long, can be found in Rhodora 72:130-136)

Bayard Long was part of an infamous botanical collecting excursion near Franklin, Virginia that resulted in nine "new to Virginia" or state record plants being found.  Long was later quoted as saying, "this is real botanizing!" in the fascinating recount of the trip (Fernald, M.L. 1937, Rhodora 39: nos 465-468) (Also reprinted by Fernald in; Contributions from the Gray Herbarium of Harvard University, 1937, and selected excerpts included in Frost & Musselman 1987: Castanea 52:16-46.)



One wonders if Pyxidanthera would have gone unnoticed had it not been for Long.  In an earlier paper on the "Plants from the Outer Coastal Plain of Virginia" (Rhodora 38: nos. 455-466), Fernald credited Long as follows, "...with his detailed knowledge of Coastal Plain plants and their proper habitats and his unequalled (sic) persistence and skill in finding them, no critical botanizing in eastern Virginia can be wholly successful without him". 

In terms of the overall significance of their botanical finds, Fernald said, "We had stumbled into what we had sought for four years, real unspoiled pine barren in Virginia".

View of "mature" longleaf pines at Blackwater Ecological Preserve, VA
perhaps not unlike what Fernald and Long would have seen if they looked up!

Today, Fernald & Long's collecting site is protected and being actively managed as Blackwater Ecologic Preserve.  Longleaf pine (Pinus palustris) is a prominent tree in parts of the Preserve, which for Virginia, is really significant. At the extreme northern edge of it's natural range, the Commonwealth is believed to support fewer than 200 INDIVIDUAL mature, native longleaf pines (Virginia Department of Forestry 2014, Status Report).

Pyxidanthera range map; 
Kartesz, J.T., The Biota of North America Program (BONAP). 2015
Taxonomic Data Center. (http://www.bonap.net/tdc). 

But back to Pyxie (Pyxidanthera barbulata). Sometimes known as Pyxie-Moss or other related and confusing common names, Pyxie is restricted to the Atlantic Coastal Plain of eastern North America.
Sorrie and Weakley 2001 (Castanea 66:5-82) recognized Pyxie as a coastal plain endemic with a bimodal phytogeographic pattern, as shown to the left.




Pyxie's distribution has a large spatial disjunction that was significantly larger until Fernald's team found it in Virginia, or as they stated, "the first station discovered between southern New Jersey and North Carolina".  According to Fernald, "Pyxidanthera barbulata literally carpeted the ground in many areas".  The best approximation of that pattern I could see today, is shown on the image below, although at this distance (and due to my lack of photographic skill) the Pyxie clumps appear almost as bare "sugar sand".

Pyxie as an abundant ground cover at Blackwater Ecologic Preserve, VA

Pyxie covered by pine needles

Frost & Musselman used Pyxidanthera as a nominal in one of the community types they recognized at Blackwater in 1987 (See citation above), while noting it only"at this one spot".  They referred to this community as "Pond Pine Flat" with both Pond Pine (Pinus serotina) and Turkey Oak (Quercus laevis) as dominants and nominals.  Interestingly, in my experience, these species usually occur in fairly different habitats and soil moisture regimes.  Fernald referred to the habitat as "thin woods of Pinus taeda and Quercus laevis".  He indicated (with a footnote) that they found this oak "to be the regular species of the area" at its northern range limit.  Much like longleaf pine, this range limit has not been significantly extended northward since then.  Turkey Oak is still found at the site but is, perhaps, not as abundant as suggested by Frost & Musselman. (I hope to address this in detail in the future).

Turkey Oak (Quercus laevis) buds (3/16/19)

Turkey Oak (Quercus laevis) stump sprouts (3/16/19), approximately 2 years after last fire; note main trunk
broken off and fallen to right of image

Pond Pine (Pinus serotina) stump sprout, same site as previous;
also approximately 2 years since last fire; note main stem still standing but dead

Since 1986, there have been approximately 16 prescribed fires here with undoubtedly significant effects. 

Structural and density differences at Blackwater Ecologic Preserve
Right: burned on ~ 2 year average return interval since 1986
Left: unburned during same interval

For now, Pyxie seems to be doing just fine! 

Spring Scourge: Lesser Celandine (Ficaria verna)

Lesser Celandine in Richmond, VA (3/18/2018)

This Euroasian member of the Buttercup family (Ranunculaceae) has been introduced in North America since at least the 1860's. It hid under the radar in North Carolina until ~ 2005 (see Krings, Weakley, Neal, and Swab. 2005.  SIDA, Contributions to Botany 21(4):2429- 2437), but has now spread to at least 7 counties and likely more.

The distribution in Virginia is shown to the right; from the Digital Atlas of the Virginia Flora. (http://vaplantatlas.org)

The plant is becoming all to familiar to many of us.  According to Meghan Fellows, speaking about the Washington D.C. area, "Yes, it is getting worse. Floods and dispersal events spread this plant throughout our area. They are also extremely good at taking over new ground. Those pesky yellow carpets of weeds have replaced what should be a bounty of spring ephemerals (and their pollinators)." (https://www.lfwa.org/updates/tips-controlling-lesser-celandine). 

According to USDA APHIS, the species is now naturalized in 26 eastern states, as well as Oregon, Washington, and several provinces in Canada (See citation below). Calling large infestations "pesky yellow carpets" is an apt description that certainly applies to areas in and around Richmond, Virginia where I have seen the species (pictured below).   

Carpet of Lesser Celandine in  floodplain forest, Richmond, VA (04/10/2018)

There is some evidence these carpets are inevitable, once the plant becomes established.  They emerge on the forest floor in the late winter before other species leaf out and produce above-ground bulbils which greatly aid in dispersal (Verheyen & Hermy 2004. J. Veg Sci 15:125-134) 

 

Plants also develop extensive tubers that easily break off with mechanical disturbance and tend to survive many above ground treatment methods.

According to M. Fellows (cited above) the spreading carpets "are painful to watch - we want to DO something. Unfortunately, science has not kept up with our need. There is NO good, reliable way to kill celandine" (emphasis added). 

There is a relatively short window between the plant's emergence and senescence when control is possible. While I am convinced that control is possible, given enough dedication and commitment, thus far, I have not shown enough of either.  I have found little evidence of anyone else who has either, but am heartened and surprised by the efforts of some seemingly unlikely groups such as the Cleveland, Ohio Metroparks (see their herculean job described here): https://bugwoodcloud.org/mura/mipn/assets/File/Educational%20Resources/Lesser%20Celandine%20Control%20Program.pdf

For conspiracy theorists, I ran across this fascinating bit on the web: "And please dear listeners and readers, don't go around trying to wipe this plant out everywhere you see it because it's on some hit list.  It's not going to go away-and that "hit list" may well have been instigated by Monsanto or some other herbicide producer. Lesser celandine stabilizes wetland area brilliantly, and the buttercup-like flowers are breathtaking in the spring" (https://www.gardensalive.com/product/lesser-celandine for-some-a-bitter-buttercup) .....WOW!

Below I illustrate examples of how this plant moves and spreads.  Perhaps they start innocuously when a homeowner acquires the "breathtaking" plant from a website much like the one I just just cited. Soon the yard is engulfed and the mowing spreads the bulbils to the neighbors. From there plants wash into an adjoining drainage swale, and eventually run down-slope into the nearest creek, where overbank flooding pushes them into adjoining riparian forests. Invariably, these riparian areas are crisscrossed by sewer lines which need to be maintained by heavy equipment which disturbs the soil, spreads the tubers to the next job site......

Ficaria verna is this house's groundcover, note rosettes in the adjoining mowed lawn

Ficaria dominates this drainage swale in the same neighborhood as previous

The bright green, linear band is Ficaria  downstream from previous;
the wet woods in the background (one of Richmond's premier parks/natural areas)
have already been invaded.

Ficaria dominates both banks of the this creekside, uprooted clumps are found washed about

Water line a few feet above a tributary to the James River, 'Nuff Said?

In 2015, USDA APHIS considered the risks of spreads and predicted the following range for Lesser Celandine.

https://www.aphis.usda.gov/plant_health/plant_pest_info/weeds/downloads/wra/ficaria-verna.pdf

Breathtaking? Absolutely!