Woody vegetation with trunks less than 2 inches in diameter or less than 10 feet tall. Also referred to as shrubs, scrub, and bushes.

Fischer, Christina et. al. (1996).  Vegetation Survey Protocol, Coyote Creek Riparian
Station in Volunteer Monitoring Protocols: A reference guide for monitoring California’s rivers, streams and watersheds.  San Francisco Estuary Institute, CA. Page 4.)