It is prolific in southern Arizona in early spring, where it is ephemeral, sometimes covering large areas in almost pure stands. May. Monolepis is a common but unimportant weed in cultivated crops, where it may flower and fruit from spring until late fall, as in the Yuma and Salt River Valleys. This plant is still used as greens by the Indians. After a wet season it contains large amounts of nitrates, which are not poisonous, but become dangerous when eaten in large amounts. A chemical reaction takes place, aided by microorganisms in a ruminant's stomach, which quickly changes the nitrates to poisonous nitrites.
Poisoning occurs so quickly that there is little time for warning symptoms.