I conducted a survey in the piedmont and coastal plain of South Carolina during 2000–2003 that documented 23 population sites in eleven counties for the recently described Rhododendron eastmanii (May-white azalea). Populations were typically located on north-facing slopes of rich, mature forests above streams dominated by oaks, hickories, and other deciduous trees. Soils had a loamy sand to sandy loam texture and were circumneutral to slightly acidic. This species is more widespread than originally thought, and botanists in Georgia and North Carolina should look for the presence of this species.

Ten species of Trillium (Liliaceae) are known to occur in Virginia. Taxonomic key, morphological descriptions, distribution maps and chromosome numbers are presented. A chromosome number of 2n = 10 was verified for: Trillium cernuum, T. erectum, T. flexipes, T. grandiflorum, T. luteum, T. nivale, T. pusillum, T. sessile, T. sulcatum, and T. undulatum. Some chromosome morphology data are applied to the discussion of T. pusillum, and also reinforce that T. sulcatum and T. erectum are separate taxa.

Pyrus calleryana, a very commonly planted ornamental tree species, is documented as an escape from cultivation in the District of Columbia and 152 counties or parishes in 25 states, and is reported as new to California, Michigan, Missouri, New Jersey, and West Virginia. Evidence is presented that the species is rapidly becoming invasive in much of its horticultural range in at least the eastern United States. Some of the escaped individuals (from 14 counties or parishes in 11 states) appear to be of hybrid origin, perhaps between callery pear and P. betulifolia or P. bretschneideri. Callery pear often produces thorny thickets as it escapes into marginal and disturbed areas, and appears to be reproducing readily in the wild.

“An ill weed groweth fast.”—John Heywood, Proverbs (1546)

We examined vegetation-environment relationships among woody species in four canopy-strata within an old-growth mixed mesophytic forest. We hypothesized that 1) the most important environmental variables determining vegetation composition would differ among canopy-layers and 2) the maximum abundance of Quercus spp. would occur under different environmental conditions than those of Acer spp. Overstory and mid-story vegetation were arrayed along gradients of soil fertility and elevation. The shrub-layer and the ground-layer were most strongly correlated with soil fertility and pH. Across strata, Quercus spp. were consistently located in ordination space on well-lit upper slopes with low soil pH. Acer rubrum was found across a wide array of environmental conditions and Acer saccharum was found in mesic areas.

The floristic composition of Beadles Barrens Nature Preserve, located in west-central Edwards County, Illinois was studied during the growing seasons of 1999–2002. The vascular flora of this 4.0 ha preserve consisted of 306 species in 75 families, including 65 species not previously reported from Edwards County. The herbaceous layer was dominated by prairie grasses with Schizachyrium scoparium (Michx.) Nash (IV = 61.5 of 100) being the most abundant. Many other prairie species were common with Soliadgo nemoralis Ait., Pycnanthemum tenuifolium Schrad. and Carex spp. having the highest importance values. Trees were sparse with most occurring in a small (0.125 ha) grove located in the northwest corner of the barrens. Tree density in the grove was 432 trees/ha with Diospyros virginiana L. (IV = 54.6) and Quercus stellata Wangh. (IV = 53.9) being co-dominants. Herbaceous species were also sparse in the grove, consisting of Danthonia spicata (L.) Roem. & Schultes, Antennaria spp., and Lechea tenuifolia Michx. The Floristic Quality Index for the site was 61.3.

Eighteen category one invasive species as defined by the Florida Exotic Pest Plant Council and nine category two invasive species are newly recorded for St. Lucie County, Florida as the result of surveys done by the authors from August through November 2003. These records document the rapid spread and need for increased monitoring of invasive species and the documentation of these specimens through the collection of herbarium voucher specimens. These records also highlight the gaps present in specimen vouchers in areas such as St. Lucie County due to a lack of monitoring.

Rockingham County, located in northwestern Virginia, is the third largest county in the state and is botanically rich and diverse. Over the past few decades, it has experienced unprecedented population growth and the loss of undisturbed habitat that accompanies such growth. This study updates the documented flora of Rockingham County, so that it may serve as a baseline for future studies, as well as provide new plant distribution information for the Flora of Virginia Project. During the course of this study, 425 numbers representing 316 species, subspecies, and varieties were collected. Fifty-two county records are reported. Five of these, Abies balsamea, Alnus incana ssp. rugosa, Calycanthus floridus var. glaucus, Scutellaria incana, and Penstemon hirsutus, are listed on the Virginia Department of Conservation and Recreation's (Division of Natural Heritage) Rare Vascular Plant List. Two others, Sanicula trifoliata and Helianthus hirsutus, are currently listed on the Virginia Vascular Plant Watch List.

Fourteen vascular plants taxa not previously documented for Pennsylvania are reported with vouchers for each county of occurrence. These include 1 lycophyte, 2 monocots and 11 dicots. Nine species are native to the United States while 5 species have been introduced to the United States.