What's the Solution?

B. Woodsorrel

Correct! The weed pictured is actually common yellow woodsorrel, a species in the Oxalis family. Yellow woodsorrel is a common summer annual weed that can be perennial in some areas. It grows on weak stems that branch at the back and generally forms roots at the lower nodes.

Although sometimes mistaken for clover or black medic when not in flower, yellow woodsorrel produces three pale green heart-shaped leaves. In the later stages, it produces small, bright yellow flowers with fire petals, which eventually turn into seedpods that expel seeds forcefully in dry conditions. Once established, oxalis can be difficult to control.

To treat emerged common yellow woodsorrel in established turf, we recommend applying Spotlight^® specialty herbicide during active growth. Spotlight provides postemergence control of Oxalis and works well as a tank mix with other broadleaf herbicides to increase the spectrum of control. Apply Spotlight at 0.38 to 0.5 fluid ounces per 1,000 square feet to get control of common yellow woodsorrel.

For optimum yellow woodsorrel control in turf or landscape ornamentals, a preemergence herbicide application is a great option. One of the following treatments is recommended:

• Gallery^® specialty herbicide at 0.38 ounces per 1,000 square feet (1 lb/acre)
• Snapshot^® specialty herbicide at 3.5 pounds per 1,000 square feet (150 lbs/acre) (landscapes only)
• Dimension^® 2EW specialty herbicide at 2.2 to 4.4 teaspoons per 1,000 square feet (1 to 2 pints/acre)

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