Volume 57 – Issue 4 (Dec 1992)

In 1983 we sampled using permanent line transects four stands of oak-saw palmetto scrub vegetation that were 2, 4, 8, and 25 years since the previous fire; these transects were resampled two years later. We sampled and analyzed soils from the 0-15 cm and 15-30 cm layer at each transect. The stands were dominated by Quercus myrtifolia, Q. geminata, Q. chapmanii, Serenoa repens, and ericaceous shrubs. Species composition was closely related to depth to the water table and related soil parameters as indicated by detrended canonical correspondence analysis ordination of vegetation and environmental data. Postfire recovery was by sprouting of the dominant shrubs with little change in species composition or richness. The initial growth of Serenoa repens after fire exceeded that of the oaks, resulting in shifts in dominance postfire. Total cover >0.5 m required six years to reach 100% and 8-10 years to reach a maximum. Total cover <0.5 m increased initially and then declined. Mean height reached one m in four to six years and continued to increase with stand age. Recovery rates have implications for the suitability of this habitat for scrub endemic species.

An oak forest in southwestern Virginia that had been sampled in 1971 was resampled in 1991. The stand was divided into an upper, drier part and a lower, more mesic part. Comparisons were made in community composition between years and between the two parts of the stand. Overall density of the dominants, scarlet oak and chestnut oak declined and basal area increased, thus indicating maturing of the community. Most notable changes over 20 years were: large increases in trees and saplings of black gum and American chestnut; Smilax rotundifolia, virtually absent in 1971, increased 16-fold in the upper stand; chinquapin of sapling size increased markedly in upper and lower stands; importance of Virginia pine increased somewhat in the upper stand, but declined to zero in the lower stand; black locust disappeared from both parts of the stand. Density of seedlings and shrubs remained rather constant as did cover % of herbs. Saplings and seedlings of chestnut oak and scarlet oak are moderately to very abundant, so these species should remain dominant for the life of the community.

Herbaceous layer vegetation was distinct among the four remaining serpentine areas in Maryland according to detrended correspondence analysis. Sorensen’s Indices of Similarity for importance values were 40.8-69.6% and 56.1-77.6% for composition. The Shannon-Wiener diversity index (H’) varied 1.88-2.49 and alpha diversity (total species sampled) from 23-33. Schizachyrium scoparium (Michx.) Nash dominated three sites, and Sporobo lusheterolepis Gray and Schizachyrium scoparium were dominants at the fourth. Twenty-two species collectively characterized the herbaceous layer of the four sites. Preliminary observations of an incidental major fire of unknown origin at one site suggested that restoration of indigenous serpentine vegetation may require cutting of coniferous trees followed by prescribed burns to control seedlings and saplings.

The Southern Appalachian Botanical Club has evolved over the course of fifty-six years from a somewhat closed organization with the limited mission of producing a journal for botanical research in the mountains of the Southeastern United States to a much expanded mission aimed toward the general advancement of interest in botany. This expanded mission is revealed by the establishment of several awards for botanical service and research, by the prodigious efforts of the Newsletter Task Force and the Outreach Committee to generate a greater consciousness and interest in botany throughout our region, and by the steady growth of our membership and of our endowment and other funds during a period of economic recession.

Chamaesyce polygonifolia and C. ingallsii are plants restricted to Atlantic coast beach communities. While C. polygonifolia is considered more common, C. ingallsii is rare (Virginia Natural Heritage Program 1989). My observations on the two species in pristine beach communities indicate that without man’s influence, the latter species may be the more common. Chamaesyce polygonifolia is a decumbent, mat-forming herb with pale green leaves, yellow stems and oblong fruits (Ahles 1968). Mats formed by this plant can be up to 30 cm in diameter

Noteworthy Collections: Tennessee

This is one of the nicest regional liverwort floras to appear in some time. It is an elegant, scholarly treatment of the North Carolina hepatics and anthocerotes designed to be used by students and naturalists. The book is divided into three main parts. The introductory section consists of a brief history, description of the area and climatic, liverwort structure, collection tips, identification guides, and the use of the keys (with a nice little section on the striking characteristics of easily recognized genera).

Trifolium calcaricum, a new species from central Tennessee and extreme southwestern Virginia, is described and illustrated. Diagnostic characters distinguishing it from its morphologically similar congeners, T. stoloniferum, T. virginicum, T. reflexum, and T. repens, are enumerated via key and discussion. Trifolium calcaricum is associated with limestone barrens and cedar glades.

This is a study of the seven species of the Fumariaceae known to occur in Virginia. The following are emphasized: keys to genera and species, morphological descriptions, distribution maps, and chromosome numbers. The following chromosome numbers are reported: Dicentra canadensis (Goldie) Walpers (2n = 64): Dicentra cucullaria (L.) Bernh. (2n = 32); Dicentra exima (Ker) Torrey (2n = 16); Fumaria officinalis L. (2n = 32); Corydalis sempervirens (L.) Persoon (2n = 32). Reported for the first time: Corydalis flavula (Raf.) DC. (2n = 16).

The plains prickly-pear (Opuntia macrorhiza Engelm.) is more abundant and wide spread in Illinois than previous publications have indicated. Populations of this species appear to be restricted to windblown sand deposits, loess hill prairies, and limestone glades along the Mississippi River, and the upper and extreme lower parts of the Illinois River. The eastern prickly-pear (Opuntia humisfusa (Raf.) Raf.) is largely restricted to sand deposits along Lake Michigan, the Illinois and Kankakee Rivers, and rock ledges of southern Illinois. The fragile prickly-pear (Opuntia fragilis (Nutt.) Haw.) is currently known from Illinois at a sand prairie in the valley of the Mississippi River in Jo Daviess County.