Life cycle
Summer annual
Growth habit
Grows up to 2' tall; entire plant appears flattened; light green to white at the base of stems.
Reproduction
Seeds
Conditions that favor growth
Mowing the lawn too short.
Goosegrass (Elusine indica). Photo: Betty Marose
Photos
Management in lawns
Maintain healthy, dense turf that can compete and prevent weed establishment. Mow lawn at 3-4 inches during the growing season and seed bare spots.
Mechanical management
Hand pulling or using an appropriate weeding tool that removes the root are the primary means of mechanical weed control in lawns. This is a viable option at the beginning of an infestation and on young weeds. Hand pulling when the soil is moist makes the task easier.
Manage Weeds Without Chemicals
Chemical prevention/treatment in lawns
Apply a granular (apply with a spreader), selective, preemergent herbicide. There are numerous products on the market. Look for a preemergent without nitrogen fertilizer. Active ingredients include: bensulide, dithiopyr (offers postemergent control on young crabgrass seedlings), pendimethalin, and prodiamine.
Rainfall or irrigation is required to dissolve the herbicide which is then absorbed into the upper portion of the soil and forms a barrier that kills weed seedlings. Preemergent grass herbicides have residual activity that lasts for several weeks after application. High temperatures and rainfall will decrease the length of time they remain at sufficient concentration to be effective.
Tips for application
- Apply prior to seed germination. For crabgrass, this begins when soil temperatures are above 55° to 60°F for 7 to10 days (during and shortly after, forsythia bloom is a rough, but not consistently reliable, guide for application timing).
- Soil Temperature Maps (linking to this site does not endorse any company, manufacturer, or product by University of Maryland Extension).
- Water after application, according to label.
- A second application may be possible, usually 6-8 weeks later (see label).
- Consult label for specific waiting period between application and overseeding.
If it is growing it can be spot treated with a postemergent herbicide before it matures and goes to seed. Look for the following active ingredients.
Common Name: Quinclorac; Trade Name: Drive; others, can be combined with other active ingredients, Common Name: Fenoxaprop-p-ethyl; Trade Name: Acclaim Extra, others.
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