You are here

Harvard Forest >

Harvard Forest REU Symposium Abstract 2007

  • Title: Do Bedrock and Soils Influence Calciphile Distribution in the West Champlain Hills?
  • Author: Peter R Jenkins (College of the Atlantic)
  • Abstract:

    The flora of the West Champlain Hills is distinct from the flora of surrounding northern forests. These hills are islands for plants more characteristic of dry, calcium-rich areas than the moist acidic woods that dominate northern New York and New England. Little is known about dry-calcareous plant communities although such sites are of high conservation value because they are uncommon and support numerous regionally rare species. An understanding of the factors that influence species distribution and diversity in the West Champlain Hills may help to inform future conservation efforts. Many plants found on upper mid-slopes with a general southern aspect in these hills are indicators of some calcium enrichment. The bedrocks in the eastern Adirondacks are primarily granitic gneisses, which tend to be calcium poor. However, metanorthosite bedrock, which contains higher amounts of calcium, extends in a band from the High Peaks to Lake Champlain and forms a number of the West Champlain Hills. We suspected that the metanorthosites along with less common metagabbros and amphibolites would produce richer soils and support more dry-rich community representatives. To determine whether bedrock type influences vegetation, we identified and surveyed dry-rich communities on nineteen hills in Essex County, NY. Nine hills were metanorthosite, two were metagabbro, and eight were gneiss. We found no real difference between the numbers of calcium indicator species on gneiss hills vs. metanorthosite/metagabbro hills. Soil pH on these hills ranged from 4.5 to 5.7 and rich indicator species did show a preference for higher pH soil. The difference between soil pH on the different rock types was not significant. Contrary to our expectations this study indicates that bedrock type does not have much influence on the distribution and diversity of calciphiles in the West Champlain Hills.

  • Research Category: Conservation and Management