[Wikipedia] Range, Toxicity, Ecology: Distribution Cryptantha affinis is native to California. Its distribution is from the Klamath, North coast, and Cascade Mountain Ranges. It also occurs in the Sierra Nevada, San Bernardino, and Warner Mountains and as far as Washington to Wyoming.[2] Most plants appear to be toxic due to their high levels of alkaloids and nitrates. Ecology Cryptantha affinis physiology appears to be influenced by nutrients of deer excretions. Increased photosynthesis and higher plant nitrogen levels have been observed in habitats frequented by mule deer, antelope, and elk. Higher nutrients appear to increase growth and reproduction in wet years. In dry years survival is increased by the shading of Cryptantha by the presence of large shrubs. Although shading increases survival in dry years, in wet years growth and reproduction seem to be reduced even when nutrient levels in the soil are high.[3] Cryptantha species are dominant annuals in a wide range of habitats.[4] In habitats where Cryptantha is a dominant species, fire intensity reduces its density.[5] (link added by Mary Ann Machi)