This weed seemed to appear overnight in 2010. It is invasive!
Catchweed bedstraw is a summer annual broadleaf plant that is starting to show in your gardens now! Its bristles attach to people’s clothing and the hair of animals, aiding in its dispersal. If you have this plant, get rid of it now. It is very distinctive with a square stem and sticky feeling.
Stems are square and have tiny down-curved prickles. Mature plants reach up to 3 feet long. Leaves whorl around the stem in groups of six to eight. Individual leaves have a rounded tip, and tiny curved prickles on the leaf edges and midveins that, under a lens, are seen pointing toward the leaf base giving the leaves a sticky touch.
Flowers bloom from March through July. Two to nine tiny, greenish to white or yellowish, four-petaled flowers cluster on long stalks from the main stem above the leaf whorls.■
-—For more information go to ipm.ucanr.edu