The mean annual temperature ranges from 48 degrees to 53 degrees F., average January temperature is 28 degrees to 30 degrees F., and average July temperature is 66 degrees to 73 degrees F. Freeze-free season is 90 to 130 days. These are the Bidwell, Bieber, Goose Lake, Modoc, Pit, and Surprise soils. Bidwell soils are well drained and have 8 to 16 inch thick mollic epipedons. Bieber soils have fine textured B2t horizons and duripans. Goose Lake soils have A2 horizons and fine B2t horizons.
Modoc soils are well drained and have duripans.
Pit soils are fine-textured and contain many slickensides. Surprise soils have cambic horizons predominantly of gravelly sandy loam. These soils were formed under wetter conditions than those that exist today. The water table normally fluctuated below 36 inches but in some places where the soil is artificially drained it is below a depth of 60 inches. These soils are used mainly for irrigated cropland or is pastured.