By Pete Fandel

Many grassy weeds thrived on all the water received this year, according to David Robson, University of Illinois Extension horticulture educator, Springfield Center. Crabgrass, foxtail, goosegrass and quackgrass are several of the problem species popping up in lawns and gardens.

Grassy weeds are difficult to control. Most are overtly aggressive and smother desirable grass species in the lawn. In garden areas, weeds seem to grow to large lengths overnight.
No chemical on the market satisfactorily controls the weeds without damaging the grass. Hand pulling and regular mowings seem to be the only options to limit seed production.
Crabgrass is the most common grassy lawn weed. Its large leaf and aggressive nature prevents bluegrass from growing adequately. Seeds germinate throughout the spring and early summer. Crabgrass is often called watergrass.
Seed heads form in late August and resemble a chicken’s foot. Crabgrass’s initial growth is upright, but mowing it causes the plant to grow horizontally. When the plant starts to flower, the first flower spikes are upright, until they are mowed. Then the plant responds by producing seed heads practically at mower level. Frequent mowings can limit next year’s crop but are not an absolute.
Goosegrass tends to be prostrate with a grayish green color and an obvious open center, whitish in color.
Foxtails are more difficult to identify. Flower stalks are usually erect and subject to mowing off. Leaf blades are as wide as or wider than crabgrass.
Quackgrass is sometimes given the name joint grass since the plant produces runners that root frequently, increasing a problem in the turf.
With the exception of quackgrass, the other grassy weeds are classified as annuals. Cooler temperatures will kill most of them, though not before they produce seeds for next year’s crop. What’s left are patches of dead turf scattered throughout the yard.
Hoeing and tilling are options to remove weeds in the garden areas. Avoid hoeing or tilling deep; most grass roots are shallow. Deep soil cultivation may damage the roots of vegetables and flowers increasing the chances of late diseases.
Make sure to remove the weeds to the compost pile. Quackgrass can root after removal and actually increase your problem.
Grassy lawn weeds may need to be spot treated with a non-selective herbicide such as glyphosate (Round-Up or Kleen-Up). Careful application of the chemical can limit damage to desirable turf. However, expect some damage to occur adds Robson. There are some selective herbicides for annual grasses, though they can be weather-influenced, especially with high temperatures and humidity. Don’t forget about hand weeding. This may be an acceptable method for limited weed infestations.
You can create a satisfactory lawn weed herbicide applicator by tying or taping a sponge or cotton washcloth to the end of a mop or broom handle. Dip the sponge or cloth in the pre-mixed chemical solution and run it across the weeds. Avoid dripping the chemical on desired species.
An old wringer/roller mop will also work adequately. Make sure the chemical bucket is large enough to handle the mop or applicator without spilling.
Read and follow all labeled directions when mixing and using the chemical.
Grass seed can be sown approximately two weeks after treatment with glyphosate. New grass seed should be sown as soon as possible after September 1 to allow for quick establishment and development before winter.
Pete Fandel is Crop Systems Educator for the Woodford County unit of the University of Illinois Extension Service; Website: http://web.extension.uiuc.edu/woodford/index.html