Definition: The U. S. Northcentral and Northeast. One of the 10 regional U.S. Army Corps of Engineers wetland delineation regions for the U.S. and its territories used by the National Wetland Plant List.
Definition: The U. S. Midwest. One of the 10 regional U.S. Army Corps of Engineers wetland delineation regions for the U.S. and its territories used by the National Wetland Plant List.
Definition: A grassland biome is a terrestrial biome which includes, across its entire spatial extent, an unbroken layer of grasses (Gramineae), sedges (Cyperaceae) or rushes (Juncaceae).
Definition: A depression caused by erosion by water or ice. Low-lying land bordered by higher ground; especially elongate, relatively large gently sloping depressions of the Earth's surface, commonly situated between two mountains or between ranges of hills or mountains, and often containing a stream with an outlet.
Definition: Of plant duration, a plant whose life span ends within one year after germination, e.g. a winter annual germinating in the autumn and flowering in the spring (esp. in Mediterranean climates), approximately synonymous to therophyte, c.f. biennial, ephemeral, perennial, c.f. also of flowering with respect to architecture, hapaxanthic, monocarpic, pleonanthic.
