New Harvard Forest Publications

The analysis of stomata in lake-sediment cores is increasingly used as a paleoecological tool. Stomata are less likely than pollen grains to be dispersed over long distances, and thus stomate records supplement and enhance interpretations based on pollen data by providing information about patterns and composition of local vegetation. We have conducted the first study of this type in New England, analyzing conifer stomata in the late-glacial and early-Holocene sediments of Berry Pond, Massachusetts. Comparison of the stomate record with pollen data tests the ability of both approaches to reflect the history of vegetation at the study site.

W.W. Oswald, B.C.S. Hansen, D.R. Foster. 2007. New England Note: Comparison of Pollen and Stomata in Late-glacial and early-holocen lake sediments from Eastern Massachusetts. Rhodora, Vol. 109, No. 938, pp. 225–229.

Harvard Forest Senior Research Fellow Aaron Ellison, along with Ph.D. student Sydne Record, 2006 REU student Alex Arguello, and Nick Gotelli (University of Vermont) inventoried the ant assemblage at Black Rock Forest in Cornwall, New York. The inventory was conducted as part of Black Rock's oak removal experiment, which parallels Harvard Forest's Hemlock removal experiment. The study also assessed the utility of different methods of sampling for ant diversity studies in the north temperate zone. Our results suggest that hand sampling and litter collection alone are adequate to identify at least 95% of the ant diversity at the site; that ant species richness in these oak forests ranges at a minimum from 38-58 taxa; and that loss of oak will likely result in an increased aboundance of Camponotus and Lasius species.

Ellison, A.M., S. Record, A. Arguello, and N.J. Gotelli. 2007. Rapid inventory of the ant assemblage in a temperate hardwood forest: species composition and sampling methods. Environmental Entomology 36: 766-775.

Aaron Ellison and his research assistant Jess Butler completed a 2-year study of nitrogen cycling dynamics in the pitcher plant Sarracenia purpurea. Their results show that most nitrogen is stored aboveground (in developing pitchers), and that root storage accounted for < 3% of the plant's overall nitrogen budget. The results suggest why this carnivorous plant has such a low photosynthetic rate, given its tissue nitrogen content. Excess nitrogen is stored for future use rather than being used immediately for enhancing photosynthesis.

Butler, J. L. and A. M. Ellison. 2007. Nitrogen cycling dynamics in the carnivorous northern pitcher plant, Sarracenia purpurea. Functional Ecology 21: 835-843.