The Klamath-Siskiyou forests are a temperate coniferous forestecoregion of northwestern California and southwestern Oregon. The ecoregion extends across 50,300 square kilometers (19,400 square miles) of the mountainous region known as the Klamath Knot. The ecoregion harbors rich biodiversity, with several distinct plant communities, including temperate rain forests, moist inland forests, oak forests and savannas, high elevation forests, and alpine grasslands. Thirty conifer species inhabit the region, including seven endemic species, making the region one of the richest coniferous forest regions of the world in species diversity. The region also has several edaphic plant communities, adapted to specific soil types, notably serpentine outcrops.
