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Acidic deposition and subsequent forest soil acidification and nutrient depletion can affect negatively the growth, health and nutrient content of vegetation, potentially limiting the availability and nutrient content of forage for white-tailed deer (Odocoileus virginianus) and other forest herbivores. Liming is a mitigation technique that can be used to restore forest health in acidified areas, but little is known about how it affects the growth or nutrient content of deer forage. We examined the effects of dolomitic limestone application on the growth and chemical composition of understory plants in an acidified forest in central Pennsylvania, with a focus on vegetative groups included as white-tailed deer forage. We used a Before-After-Control-Impact study design with observations 1 year before liming and up to 5 years post-liming on 2 treated and 2 untreated 100-ha sites. Before liming, forage availability and several nutrients were below levels considered optimal for white-tailed deer, and many vegetative characteristics were related to soil chemistry. We observed a positive effect of liming on forb biomass, with a 2.7 fold increase on limed sites, but no biomass response in other vegetation groups. We observed positive effects of liming on calcium and magnesium content and negative effects on aluminum and manganese content of several plant groups. Responses to liming by forbs and plant nutrients show promise for improving vegetation health and forage quality and quantity for deer.

Twenty-one adult raccoons (Procyon lotor) were radio-marked on each of two areas in Centre County, Pennsylvania from 17 June to 23 August 1987. Raccoons on Area 1 were vaccinated with a commercial inactivated rabies virus vaccine administered intramuscularly, whereas on Area 2 raccoons were not vaccinated. Survival rates were estimated for three periods: pre-season (23 August to 23 October 1987), harvest season (24 October 1987 to 23 January 1988) and post-season (24 January to 26 March 1988). Kaplan-Meier survival rates (+/- SE) were 1.00 +/- 0.00 for both areas during the pre- and post-season periods. Survival rates during the harvest period were 0.67 +/- 0.11 and 0.69 +/- 0.11 for Area 1 and Area 2, respectively. Survival rates between the two areas were not different (P = 0.929). During 23 August 1987 to 26 March 1988, rabies was not an apparent factor in raccoon survival. Conclusions regarding timing an oral rabies vaccination campaign based upon occurrence of rabies-related mortalities could not be presented because of the lack of obvious rabies mortality. However, our findings, combined with information about immunization, vaccine distribution, and peak periods of raccoon rabies, suggest a late winter or early spring vaccination period would be optimum for reducing the number of raccoons susceptible to rabies.

A serologic survey of 60 eastern cottontail rabbits (Sylvilagus floridanus) from three counties in Pennsylvania was conducted in March 1983. Serum antibody prevalences for Herpesvirus sylvilagus and La Crosse virus (California serogroup) were less than 4%. There was no evidence of previous exposure to either Jamestown Canyon or snowshoe hare viruses (California serogroup). Antibody to trivittatus virus (California serogroup) was found in 60% of the 20 cottontails from York County. No cottontails had antibodies to Bacillus piliformis, the etiologic agent of Tyzzer's disease.