Epilobium minutum
Epilobium minutum is a species of flowering plant, known by the common names little willowherb, chaparral willowherb and desert willowherb, in the family Onagraceae. It is also called "smallflower willowherb" in reference to its relatively small size. However that name, in particular the British English variant "small-flowered willowherb", typically refers to Epilobium parviflorum.
This annual wildflower is native to western North America from British Columbia and Alberta to California and Arizona. This is a plant of fields and meadows, including vernal pools, and it is one of the first flowers to spring up in areas recently cleared by wildfire.