Crab grass and Pre-Emergent application i

Asked March 27, 2015, 10:51 PM EDT

Can you please tell me what chemical is commonly used as a Crab grass and Pre-Emergent application? Is it toxic to birds, pets and does it get into the water table via storm drains? If applied in the wind, is it carried airborne? Thank you.

Montgomery County Pennsylvania weed issues horticulture

1 Response

Hello and thanks for using the Ask an Expert System.

I suggest that you refer to Penn State Extension Fact Sheet Control of Summer Annual Grass Weeds in Turf Grass. This is available free at

You will discover that there are at least 10 different preemergence herbicides listed for use in Pennsylvania. Not all of these are available to home owners.

You should carefully read the label of any herbicide you use for information on safe handling of the chemical. Most of these are relatively safe when used as directed. If you own a dog or cat you should keep them off the treated areas for at least the amount of time listed on the label. Any chemical applied in the lawn will get into the water table. The quantity that escapes depends on the amount of chemical applied. Once again following the directions and avoiding application when rain is expected will limit the amount of chemical entering ground water. Applying any chemical on a windy day will result in some air dispersal. Naturally you will want to take all precautions listed on the label to protect yourself, your pets and the environment.

If you have additional questions please contact your local Penn State Extension Office. The Montgomery County Penn State Master Gardener’s hotline can provide specific information and recommendations for your area. You will find information on the hotline at.

Montgomery County Penn State Extension
Address: 1015 Bridge Road, Suite H, Collegeville, PA 19426-1179
Phone: 610-489-4315
Office Hours: Monday-Friday 8:30 a.m. - 4:30 p.m.