Click on image to view larger version.
Figure 1. Albers equal-area projection of a portion of the north-central and northeastern USA, showing the location of 34 prairie remnant sites that were the source of 46 switchgrass accessions collected in 1997 and 1998. The site to the east of Michigan's Lower Peninsula (HI) is on Hansen's Island in Lake St. Clair. The USDA hardiness zones (HZ) 3, 4, 5, and 6 are identified on the map (Cathey, 1990). All sites were located within the Eastern Broadleaf Forest (Continental) ecoregion, with the following exceptions: Sites CH and RF in the Prairie Parkland (Temperate) ecoregion; Sites AN, AS, MO, and SB in the Laurentian Mixed Forest ecoregion; and Sites SA and YC in the Eastern Broadleaf Forest (Oceanic) ecoregion (Bailey, 1998).
