Records of counts of the different microscopic species in a core, soil, sediment, rock or water sample to determine geologic age or other characteristic of the sample. Use for microscopic examinations.
Constructed farm ponds represent significant breeding, rearing, and overwintering habitat for amphibians in the Driftless Area Ecoregion of Minnesota, Wisconsin, and Iowa. Links to fact sheet, brochure, annual reports, field manual, and final report.
U.S. Department of the Interior |
U.S. Geological Survey