18 to 120 inches. Growing Season . 25 to 225 days. Surface Water Characteristics . Many rapid or moderately rapid flowing rivers and streams.
Most rivers flow westerly in deeply incised canyons with bedrock controlled channels.
Some easterly flowing streams in deeply incised canyons flow inland to the Sacramento River. Some water is diverted from the westward flowing Trinity River system eastward to the Sacramento River. Numerous lakes and meadows associated with glaciated areas above 5,000 feet. Disturbance Regimes . At higher elevations, historic occurrence has changed from infrequent, low and moderate intensity ground fires to infrequent, low, moderate and high intensity surface or stand replacing fires.