Northeast Ohio Weed Alert: Crabgrass, Nutsedge, and Oxtails
By Rick Pietrick
With the recent rise in temperature, new “summer annual” weeds have begun to germinate. Usually found in the bare areas of the lawn, these late germinating weeds can fill areas that lack sufficient turf coverage or even spots in the lawn that were previously treated with a spring weed control.
Here is what we are seeing in Northeast Ohio.
This late germinating weed is very prolific. It is fairly easy to get rid of but will reproduce throughout the summer making control in higher temperatures cumbersome. Oxalis will invade bare or thin areas. It has a clover-like green or purple leaf with a small yellow flower. Keeping your lawn thick with proper fertilizing (over-seeding if necessary) and mowing high are good ways to prevent Oxalis from germinating in your lawn.
Crabgrass seeds germinate when soil temps are over 60 degrees for at least a week continuously. Usually the 4th of July is a consistent marker for its appearance. It tolerates hot and dry conditions very well and will grow in any bare areas of your lawn. Most lawns will have crabgrass in the die-back areas along the road and curbs. There is no true “post-emergent” spray but you can treat crabgrass with an application that will control the plant and prevent it from growing any bigger. Re-seeding the bare/thin areas of your lawn will prevent crabgrass from coming back next year.
Nutsedge is a light green or yellow grass-like weed. It is usually seen protruding above your normal turfgrass. Nutsedge comes into the lawn with soil placement or poor-quality seed. It thrives in water logged soil, but once established, can tolerate normal conditions and drought. It tends to be difficult to control because it will reproduce itself underneath the soil and re-emerge later. Herbicide can be used but it is also effective to remove the plant by hand.