Native to Europe but distributed throughout the world.
A perennial weed common in turf, landscape, crops, and nurseries. Plants spread by the underground rhizomes as well as from seeds, and seeds are thrown up to 12 feet from the parent plant by the explosive nature of the seed pods.
Very similar superficially to Creeping woodsorrel, but plants tend to grow much higher, as tall as 10 inches due to the more upright stems. In addition, yellow woodsorrel has rhizomes while creeping woodsorrel has stolons.
Leaves are clover-like, with three heart-shaped leaflets on long stalks. After sunset the leaflets tend to fold down along their stems. Flowers are yellow and may grow in small groups of up to six flowers, each on a long stalk. Flowers are very small but open wide, and have 5 petals. The seed pod is a cylindrical capsule up to an inch long, often pointing vertically. It contains many seeds, and is capable of throwing these great distances as it pops open. Seeds also have a sticky coating and may be carried in animal fur.
Characteristicts Important to Control:
Physical removal of individual plants in non-turf areas may be moderately successful, but rhizomes easily can be left behind to create new plants.