Rio Bosque Wetlands Biological Treasure Hunt

This is one of many wildflowers in the Aster family that produces showy yellow flowerheads during the summer and fall. Like other species in its genus, the flowerheads of Bitterweed have very distinctive petal-like rays with broad 3-toothed tips. Bitterweed is also distinguished by its very narrow leaves (less than 1/8" across) that are nearly filiform; they often occur in short clusters along the stems. Other Helenium spp. in Illinois have wider leaves and they prefer habitats that are more damp. less ↑

Pluchea sericea, commonly called arrowweed, is a rhizomatous evergreen shrub of riparian areas in the lower Sonoran Desert and surrounding areas. It is common in the lower Colorado River valley of California, Nevada and Arizona, as far east as Texas, and in northern Mexico where it often forms dense impenetrable thickets. Arrowweed can reach over 3 meters in height, their long straight stems were used by Native Americans to make shafts for arrows. less ↑