Volume 75 - Issue 1 (March 2010)

ABSTRACT Temperature drives ecosystem function and can be estimated from potential solar irradiation (the surface angle of the Earth in relationship to the sun). However, indirect topographical proxies (i.e., aspect) are often used in lieu of direct temperature estimates; and temperature models based on potential solar irradiation typically omit elevation, a key parameter in temperature estimation. Using temperature data (2002–04) from regional weather stations and field sites in the southern Appalachian region of North Carolina and north Georgia, I test the efficacy of temperature estimations based on potential solar irradiation and present a simple method to improve such estimations by incorporating elevational temperature gradients. The heat load index, which weighs afternoon sun as more integral to heat generation than morning sun, fits actual weather station and field site temperatures better than solar angle alone. However, in all years and data sets, adjusting the heat load index for elevational substantially improves its fit with actual temperatures. Further, by calibrating the adjusted heat load estimation with annual weather station temperature data, actual field site temperature for individual years can be accurately predicted. This paper presents a relatively simple method for generating temperature data that requires only spreadsheet or statistical software. This is useful for estimating temperatures from data sets where only topographical or GPS data were collected. It also can be used to derive missing data when sampling sites outnumber temperature loggers.

ABSTRACT Blackland prairies are a globally imperiled, rare plant community only recently discovered in central Georgia. A floristic inventory was conducted on six remnant blackland prairie sites within Oaky Woods Wildlife Management Area, 12 km southeast of Warner Robins. The 43 ha site complex yielded 351 species in 219 genera and 89 families. Four species new to Georgia were documented. According to several state and federal rankings, twenty-three rare plant species occur within the study area; these include one federally endangered species (Silene catesbaei) and one candidate for federal listing (Symphyotrichum georgianum). Twelve plant communities are described. The inventory supported the designation of a new ecological association, the Georgia Eocene chalk prairie. Maps of the study area and photographs of the prairies and rare plants are provided.

ABSTRACT The vascular flora of the North Chickamauga Creek Gorge State Natural Area (NCCG) was studied during three growing seasons from 2006 to 2008. NCCG is located in Hamilton and Sequatchie Counties, Tennessee, on the eastern edge of the Cumberland Plateau. Within the study area are 2,862 ha of eastern deciduous forest that contains 12 distinct habitat types. A survey of these habitat types yielded 110 families, 329 genera, and 604 species or lesser taxa, including 238 county records. Seventy-six introduced species were found, comprising 13% of the total flora. Eleven species with either a state or federal listing were documented: Castanea dentata, Diervilla lonicera, Diervilla rivularis, Glyceria acutifolia, Nestronia umbellula, Spiraea virginiana, Scutellaria montana, Sabatia capitata, Woodwardia virginica, Panax quinquefolium, and Viola tripartita. A species-area curve for the Cumberland Plateau of Tennessee was constructed from the current study and seven other similar studies of the plateau. Three family level species-area linear regression lines were also constructed, demonstrating that the natural area reaches or exceeds expectations for Asteraceae, Poaceae, and Cyperaceae.

ABSTRACT Although the Appalachian Mountains of southwestern Virginia, United States, are known to represent a major ‘hotspot’ of biodiversity for North America, no significant survey of overall lichen diversity has been conducted in the region thus far. Presented here is a list of 221 distinct taxa of lichens, lichenicolous fungi, and ‘lichen allies’ collected during the 2008 Hugo L. Blomquist Bryological and Lichenological Foray in the mountains of southwestern Virginia. Collections were made from diverse habitats, primarily in the Mount Rogers National Recreation Area (MRNRA), and yielded 41 potential state records. Particularly noteworthy collections include: Sphaerellothecium coniodes (a lichenicolous fungus that was not previously known to exist in North America), Hypotrachyna lividescens (a primarily neotropical macrolichen that has not previously been reported from North America), Pycnora praestabilis (a lignicolous crust not previously reported from any other location in eastern North America), Heterodermia erecta (a foliose lichen previously known in the world only from a single small region of Georgia/North Carolina), and Psilolechia clavulifera (a crustose lichen taxon previously reported from only one other location in eastern North America). The sheer diversity of lichens, along with the number of rare and/or potentially endangered taxa, highlights the need for continued preservation efforts in MRNRA and the southern Appalachian Mountains in general.

Claytonia rubra (T.J. Howell) Tidestrom ssp. rubra (PORTULACACEAE)—Arlington County: rim of Potomac River Gorge, 25 m from George Washington Memorial Parkway roadside, 100msouth of first overlook, 7 April 2009, Steury 090407.1 {CM, George Washington Memorial Parkway Herbarium, UC}.

Significance. This is the first record for Eastern Kartesz 1999, Miller 2003). Claytonia rubra (red-stem springbeauty) is native to western North America, north to southern British Columbia, Canada, south to southern California and near northern Arizona, all along the West Coast, and east to Colorado (one station) and eastern South Dakota (Miller 2003). It is an annual, or sometimes overwintering and biennial, prostrate herb, bearing minute tuberous bodies on the root hairs (Miller 2003).Within its native range, it occurs on vernallymoist dunes, in coniferous forest or scrub, in sun or shade (Hickman 1993). In Virginia, 163 flowering plants were found over an area of 28 m 3 3 m along the ecotone of a cliff bluff dominated by deciduous trees and shrubs and a grassy roadside, on bare, open, mossy ground that is vernally in full sun, but mostly shaded by late spring. The dominant associated species was the non-native herb Veronica hederifolia L. The only native species observed within the Claytonia rubra population were Carex pensylvanica Lam., Eurybia divaricata (L.) Nesom. and over hanging branches of Juglans nigra L. and Cornus florida L. All other associates were non-native, including Poa annua L., Lamium purpureum L., Stellaria media (L.) Vill., Cruciata pedemontana (Bellardi) Ehrend, and Scleranthus annuus L.

Portulaca amilis Speg. (PORTULACACEAE)— Lowndes County: Columbus, in a weedy, infrequently mowed lawn directly along the east roadside at 2120 US Highway 45/ State Road 50 (N33 31.379, W88 26.135), about 50 yards north of the intersection with Hospital Drive; 17 Aug. 2008, Maggie Whitson 2008-0002 with Mona and Jim Whitson (KNK).

Significance. The South American native, Portulaca amilis, was first reported to occur in the United States in 1981 (Judd andWunderlin). That paper cited collections from Florida, Georgia, North Carolina, and South Carolina, with the oldest (1956) being from North Carolina. A North Carolina specimen dating to 1932 has since been found, as well as a collection for Virginia (Matthews and Levins 1985). The treatment in Flora of North America indicates that P. amilis also occurs in Alabama (Matthews 2003).

Eleocharis melanocarpa Torr. (CYPERACEAE)— Bienville Parish: Sandylands NE of Piney Woods Road (PR 676), 0.8 km E of bridge over Kepler Creek Lake

Significance. The above-cited specimens represent the first recorded population of Eleocharis melanocarpa in Louisiana, as applicable sources do not report this species for the state (Thomas and Allen 1993, United States Department of Agriculture, Natural Resources Conservation Service [USDA,NRCS] 2008, NatureServe 2008, Smith 2002).

ABSTRACT Woody grapevines (Vitis spp.) are common in the deciduous forests of the southeastern United States. Their growth habit makes leaf collection challenging and polymorphic leaves make identification of species difficult. Mature grapevines can grow up to 48 cm in diameter at breast height and reach the upper canopy of trees more than 35 m in height. Leaf morphology is the most readily available character used for species identification. However, most mature grapevines do not produce leaves below the upper canopy and if they do, these leaves are morphologically indistinguishable from other species. In order to sample leaves from mature grapevines, the doubled rope climbing method was used to access the canopy in Great Smoky Mountains National Park in Tennessee, Daniel Boone National Forest and Berea College Forest in Kentucky, and Ha Ha Tonka State Park in Missouri. Leaf voucher specimens were collected from the upper canopy and used to create a modified key to species for those regions. The purposes of this paper are to report a new method for collecting grapevine leaf vouchers from the upper canopy of trees, to present a modified key used for identifying dried leaf vouchers of Vitis species, and to present a discussion of the possible utility of this research for future studies.

Shores, E.F. 2008. On Harper’s Trail; Roland McMillan Harper, Pioneering Botanist of the Southern Coastal Plain. University of Georgia Press, Athens, Georgia. $42.95. ISBN 10: 0- 8203-3100-7, ISBN-13: 978-0-8203-3100-3.