Oxalis

Oxalis can be identified by its green to purple stems that are mostly unbranched, but branches sometimes grow from the base of this broadleaf weed. Its leaves grow on long petioles with three heart-shaped leaflets. Often confused with Clover, Oxalis leaves often fold up during midday and night. In bloom, Oxalis features small yellow flowers with five petals that occur in clusters. Reproduction occurs by seeds, which explode out from the pods and can scatter considerable distances.