Grindelia (gumweed) is a genus of plants native to the Americas belonging to the sunflower family. The genus was named for Latvian botanist David Hieronymus Grindel, 1776–1836.They are herbaceous plants or subshrubs with annual, biennial, or perennial life cycles. The flowerheads are composed of numerous yellow disc florets (usually between 100–200) and from 0 to sixty or more yellow or orange ray florets. Grindelia squarrosa, a plant with bright yellow flowers indigenous to much of the United States, ...