Gumweed (
Grindelia squarrosa) is an erect annual, biennial or short-live perennial flowering herb that is a member of the sunflower family (Asteraceae). It is native to western and southwestern North America.
G. squarrosa has alternate leaves with gland-dotted, toothed edges and gummy appearance. It produces numerous yellow flowers.
G. squarrosa utilizes a deep taproot and an extensive shallow root system.
Toxic components
G. squarrosa is able to absorb high levels of selenium in certain soils, which can cause
selenium toxicity. Most horses avoid the plant, however if there is little else to eat horses may consume the plant from hunger.
