Without periodic fire, historically open-canopied, oak-dominated upland woodlands of the central and eastern United States are shifting to closed-canopied forests with increased abundance shade-tolerant typically fire-sensitive species. Once established, these encroaching species (i.e., mesophytes) hypothesized initiate a positive feedback termed mesophication where mesophytes perpetuate condit...

The ages of fluvial deposits at the head of Chesapeake Bay, thought to be the updip, chronostratigraphic equivalents of a well-dated late Oligocene to Quatemary marine sequence in the Salisbury Embayment, are poorly known. We present data regarding a new occurrence of a palynoflora recovered from the Bryn Mawr Formation in Cecil County, Maryland. The floral assemblage for the Bryn Mawr Formatio...

Greenhouse and laboratory studies were conducted to determine the identity and pathogenicity of Diaporthe– Phomopsis species complex recovered from eight weed species. The identifications of the eight isolates representing four taxa, including two apparently undescribed species of Phomopsis, were based on colony features in pure culture, morphology of alpha or beta-conidia, and internal transcr...

We examined phylogenetic relationships of the North American chorus frogs (Pseudacris: Hylidae) from 38 populations using 2.4 kb of 12S and 16S mtDNA to elucidate species relationships and examine congruence of previous phylogenetic hypotheses. Parsimony, maximum likelihood, and Bayesian phylogenies are consistent and reveal four strongly supported clades within Pseudacris: (1). A West Coast Cl...

Crop rotation is a common means of reducing pathogen populations in soil. Several rotation crops have been shown to reduce soybean cyst nematode (Heterodera glycines) populations, but a comprehensive study of the optimal crops is needed. A greenhouse study was conducted to determine the effect of growth and decomposition of 46 crops on population density of H. glycines. Crops were sown in soil ...