Saturday, May 31, 2014

Lost & Found: Bog Rose

Bog Rose in NC where it was recently rediscovered
Bog Rose a.k.a Dragon's Mouth Orchid (Arethusa bulbosa) is endangered in North Carolina. Originally known from only a small handful of sites it is unclear if it still persists at most of these. Dedicated orchid enthusiasts, including Mark Rose & David McAdoo, have been searching remnant mountain bogs for nearly 20 years hoping for a glimpse of it in North Carolina.

It is unclear why this orchid has become so hard to find in NC, although Mark Rose believes heavy shrub invasion in its bog habitat may be a contributor.  In more northern parts of its range (where it is much more common), "many populations have been depleted or destroyed by over-collection. ( I recently heard of a site in Transylvania County which once had 20 or more stems, that was destroyed by silt washing in from a nearby pasture.

The site where Bog Rose has been recently re-discovered had become heavily invaded with shrubs especially Rhododendron. After protecting the site from development and other forms of incompatible land-use, we began a restoration project. Using chainsaws and machetes, we removed massive quantities of woody stems to return the site to more open condition and conducted a prescribed burn. Approximately 2 years after the bulk of the clearing the Bog Rose has re-appeared!
One of the many piles of Rhododendron stems removed from the mountain bog habitat of Arethusa.
Bog Rose plants recovering from decades of  suppression.
Photo courtesy of Jean Woods (Left)
Possibly, the last home for the Bog Rose is now a North Carolina Plant Conservation Preserve. Restoration work has produced results and this, and other, rare plants are rebounding.  At the moment only 2 flowering stems have been found. Let's hope orchid enthusiasts and collectors respect the Preserve designation and the work it has taken to restore, and leave the Bog Rose for the enjoyment of future generations

Mountain Sweets - Almost Gone?

                                                                                                                                                                                                                                                                     One of the sweetest plants to find in the Southern Appalachians, perhaps, because it is one of the most unexpected, is the trumpet-like pitcher plant known as Sarracenia jonesii. With a natural range centered on Henderson County, NC this carnivorous plant is a relatively narrow endemic just barely ranging into South Carolina. In a region most noted for forests, this pitcher plant inhabits small wetland pockets often referred to as "mountain bogs".  

Range map for Sarracenia jonesii in NC; "extirpated" refers to sites formerly known to support the species but lost for one reason or another, while "extant" refers to naturally occurring populations still present, unless indicated as "extant-introduced" which are sites created by planting in a non-naturally occurring site.

Only three naturally occurring populations remain in North Carolina.

A quick review of the distribution map tells a tale of substantial decline, in which most of the known, naturally occurring sites have been lost.  In 1986, the USFWS listed the plant as endangered.  What happened to cause the decline and create the need for federal listing?

Like many areas of the country, wetlands in this part of NC have not fared well. The first map below portrays the predicted extent of historical wetlands in the heart of the Mountain Sweet range (polygons shaded light blue). The second map illustrates those same wetland areas with the current land use depicted; bright red and yellow colors show heavily altered or otherwise developed areas. A comparison of the two gives a clear illustration that substantial wetland area has either lost or heavily altered.

                                                                                                                                                                              In addition to habitat loss, other Mountain Sweets have been lost due to poaching and over-collection by hobbyists. An example of this phenomenon is the extirpation from the wild of a "green race" of Sarracenia jonesii.   There still appears to be ample pressure collecting pressure on the few remaining native populations.                                                                             

Must we have every species in our gardens?

Wednesday, May 28, 2014

Lost & Found: Bent Trillium

After a recent speaking engagement for the Saluda Community Land Trust (SCLT) I was invited to visit a privately owned property. Having driven through the local area, I was dismayed by the extent and domination of invasive plants and didn't set my sights too high.

Multiflora Rose (Rosa multiflora)
eating up the woods in Polk County, NC

However, it was soon apparent this site was a wildflower paradise. A host of spring flowers and native plants clothed the ground including a number of Trilliums. It didn't take long to recognize that I didn't recognize them all! After some research, I began to suspect an unusual species for North Carolina was present. Rumour had it that the NC Native Plant Society had previously been to the site. I checked with Tom Harville and Mark Rose and, sure enough, they indicated seeing at least two Trilliums of special conservation interest in North Carolina. Based on these reports and my own observations, I was able to convene a "Trillium Dream Team" of sorts to revisit the site and attempt to officially document the various species present.

3 members of Trillium Dream Team
Tom Patrick, David Campbell,
 Jim Matthews

Tom Patrick (GA DNR), Jim Matthews (UNCC retired), David Campbell (UNCC Herbarium), James Padgett (NC Natural Heritage Program), Kathy Schlosseer (PCP Board Chair), Mimi Westervelt (FOPC member extraordinaire) met on-site in early May.

It wasn't long before Jim, David, and James were building a plant list for the property, adding a host of species to the list the landowner had previously assembled. Just a short walk down the trail we found the main target of our efforts.

Bent Trillium (Trillium flexipes) rediscovered in NC near Pacolet Falls

Bent Trillium (Trillium flexipes) has a wide geographic range in eastern North America, centered in the Midwestern states (see below). This Trillium is considered "globally secure" by NatureServe and the network of Natural Heritage Programs.  However, the species trails off in the south, just barely reaching north Georgia, Alabama, and Mississippi. Here in North Carolina the species has been reported from 3 western counties all of which are considered to be "extirpated or possibly extirpated".

With this confirmation and "re-discovery", Bent Trillium is once again considered an extant member of our native flora. We hope to continue working with the private landowner to protect this important site for posterity.  The NC Plant Conservation Program has set a goal to permanently protect each native plant species in its natural habitat; this site is a "no-brainer"!

Sweet White Trillium (Trillium simile) near Pacolet Falls

Another significant species documented during our visit is Sweet White Trillium a.k.a Jeweled Wakerobin. In contrast to the wide distribution of Bent Trillium, Trillium simile is a narrow Southern Appalachian endemic found only in TN, GA, SC, and NC. NatureServe ranks it as globally vulnerable and the NC Plant Conservation Program considers it to be threatened and thereby worthy of protection efforts.

Tuesday, May 27, 2014

Shortleaf Pine (Pinus echinata) - Carolina Piedmont

Shortleaf Pine woodland with Post Oak (Quercus stellata) and Blackjack Oak (Quercus marilandica), Durham Co., NC

Increased attention is being focused on shortleaf pine by some foresters, ecologists, and restoration practitioners. An ongoing debate centers on how much shortleaf was present historically relative to the other native pines and hardwoods. We may never know the answer, however, it seems probable in our region (N.C. Piedmont) that mixed forest prevailed. According to Pinchot & Ashe 1897, " areas in the original forest...produce pure growth of either"

{The native range of Pinus echinata}
Range Map for Pinus echinata;

Although the preceeding map shows shortleaf ranging into the outer coastal plain there is general consensus that most of this area was historically dominated by other vegetation, especially longleaf pine woodlands and savannas. However, in the Piedmont there are intriguing "remnants" of shortleaf woodlands or savannas which share structural and compositional similarities with longleaf pine communities. 

Open Shortleaf Pine with herbaceous
understory including Indiangrass (Sorghastrum nutans)
Open Shortleaf "savanna"
 another view of well burned patch in Durham Co, NC

There is growing recognition that prescribed fire is an important management and ecological restoration tool in many shortleaf pine stands. To return long-suppressed stands to more open condition (such as the images above) frequent, regular fire is desirable. We try to burn these areas in the early spring on a 2-3 year rotation. 

Shortleaf Pine - Oak Forest; Spring 2014 prescribed fire
In the stand above, the nearly closed canopy from abundant oaks, especially Southern Red Oak (Quercus falcata), allows only patchy sunlight to reach the forest floor. Although fuel conditions were quite dry, the lack of sunlight penetration and wind movement underneath the trees and relative humidity in the high 30's fostered slow moving low flames and incomplete ground coverage.  

May 2014 Prescribed Fire in Shortleaf Pine - Oak Forest. Poverty Oat Grass (Danthonia spicata) is abundant and flowering in the left side of this view.  Patches of live green vegetation contributed to patchy coverage of this growing season burn.

Shortleaf Pine sapling on site burned ~ biennially for 10 years.
The small needles provide less surface for ice damage
than loblolly pine (Pinus taeda),
possibly explaining  its more northerly distribution.