Forest and Kim Starr, Starr Environmental, Bugwood.org
Woodsorrel, creeping is a summer perennial that has hairy stems, slender taproots and bright yellow flowers with five petals. The flowers form in clusters up to five at the end of the stems. The leaves of this weed are deeply loped and heart shaped and may appear green or purplish-red.
Mowing, fertilizing and irrigation are bad practices when trying to control and eliminate woodsorrel, creeping. In fact, these practices may cause this weed to spread more rapidly. Once it establishes in the turf, it's very competitive and will choke out grass and other plants. Postemergent control is ideal using a product containing triclopyr. Using a pre-emergent herbicide in the spring is also helpful to kill the seedlings and to prevent this weed from growing and spreading.