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FAQs - Lawns - Weed Management - Spring

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My lawn has numerous weeds. I am thinking about applying a weed killer.  I found a liquid herbicide that this is labeled to kill many different kinds of weeds. It should do the job. Is there an alternative to killing weeds without harming wildlife near the yard, the environment, etc.?

My lawn is being overrun with a weed that is spreading very quickly. It started on the shady edges of the lawn and is now moving into the sunny areas. It is a low spreading plant with square stems, green round leaves with curly margins and small purple flowers. How do I get rid of this weed without damaging my grass?

This past summer I had the worst crabgrass problem in my lawn. Now that spring is approaching what can I do now to prevent it from coming back?

What is this new weed I keep seeing in my grass? In fact I am seeing it everywhere this spring. Some of the flowers seem to be changing from white to a purplish color and it looks like they are developing 'needles' on the stems. What should I do?

We need to remove the clover from our lawn and reseed, but we have just gotten a puppy.   He loves to run in the grass. What do you recommend? Also, can you recommend an alternative to kill clover without using an herbicide? I was reading an article about corn gluten and was wondering if we can use that.

Moss is taking over my lawn. What can I do to stop its spread? Should I just apply some lime to my lawn?

My lawn has numerous weeds. I am thinking about applying a weed killer.  I found a liquid herbicide that this is labeled to kill many different kinds of weeds. It should do the job. Is there an alternative to killing weeds without harming wildlife near the yard, the environment, etc.?

Before using an herbicide, it is important to identify the weeds growing in your yard. If your lawn consists of over 50% weeds, lawn renovation is probably in order. The time for a renovation project would not be now, but in the late summer into early fall. There are very few effective organic herbicides for lawns. The most environmentally sound alternative is to tolerate some weeds and lessen the amount of them with proper turf management practices. See our lawn maintenance publication, (PDF) HG112 Turfgrass Maintenance Calendars for Maryland Lawns for lawn care tips.

My lawn is being overrun with a weed that is spreading very quickly.  It started on the shady edges of the lawn and is now moving into the sunny areas. It is a low spreading plant with square stems, green round leaves with curly margins and small purple flowers. How do I get rid of this weed without damaging my grass?

This sounds like ground ivy or creeping Charlie (Glechoma hederacea).  This perennial weed is difficult to control because it creeps along the ground forming dense mats of stems.  The foliage emits a mint-like odor when crushed. The best time to control it is in the late summer to early fall. Look for a broadleaf herbicide containing two or three different active ingredients. Or products containing the chemical triclopyr are reported to provide better control.  Two applications are usually necessary. The second application should be 14 days after the first. As always, when using pesticides, read and follow label directions carefully.  Controlling ground ivy takes time and persistence.

This past summer I had the worst crabgrass problem in my lawn. Now that spring is approaching what can I do now to prevent it from coming back?

Crabgrass is one of the worst turf weeds in Maryland. It is best controlled by applying a crabgrass preemergent in early spring. If crabgrass pressure is heavy, a second application may be necessary 6 weeks after the first.  Read the product label for important information regarding application and make sure the product you select does not contain fertilizer! Treating crabgrass after it has emerged is possible if you treat it with an herbicide labeled for crabgrass control and the weed is young. Once it matures and becomes larger herbicides are not effective. To improve the quality of your lawn mow to a height of 3-4 inches and, if necessary, overseed in late summer-early fall.

What is this new weed I keep seeing in my grass? In fact I am seeing it everywhere this spring. Some of the flowers seem to be changing from white to a purplish color and it looks like they are developing 'needles' on the stems. What should I do?

What you are noticing is a weed called hairy bittercress (Cardamine hirsuta). This is a weed of both lawns and planting beds. Pull it quickly! Those 'needles' are seed pods that will explode, open and project their seeds everywhere. Though flourishing now, this is a winter annual weed, most of its seeds germinated last fall. It grew quietly all winter and now is getting ready to complete its life cycle by producing seeds. The weed itself does not persist into the summer but the seeds are in the soil ready to germinate when conditions are right. Handpull or mow soon to remove the seedheads  before the plants mature. This one time bagging the clippings is recommended.

We need to remove the clover from our lawn and reseed, but we have just gotten a puppy.  He loves to run in the grass. What do you recommend? Also, can you recommend an alternative to kill clover without using an herbicide?

I was reading an article about corn gluten and was wondering if we can use that. If you really want to eliminate the clover (clover seed was actually mixed with grass seed up until the fifties), you will have to use chemicals that will require you to limit your puppy's activity for a period of time. Unfortunately, there are no organic herbicides for selective control of weeds in lawns. There are several herbicides labeled for the control of clover without hurting your turf grass, among them: Trimec® (a combination of 2, 4-D, MCPP, and Dicamba), or Triclopyr.  Many companies market these products, so make sure to read the labels of several brands before purchasing and then read the label carefully before applying.  Typically, pets should be kept off liquid spray herbicides until they have thoroughly dried, but again, read the label. You can also check with the National Pesticide Information Center.

Moss is taking over my lawn. What can I do to stop its spread? Should I just apply some lime to my lawn?

(PDF) Moss in a lawn is an indication of poor growing conditions for the turf, the lawn thins out and the moss moves in. Soil compaction, acidic soil, shade, poor drainage, and low fertility will cause the grass to thin out. If possible, these conditions must be corrected and proper lawn care practices introduced or the moss will continue to thrive. It is very difficult to grow grass in the shade underneath trees.  Consider reducing turf areas by installing pathways, mulching around the trees and planting a shade-loving groundcover. 

Please send us a question at Ask the Experts if you have a lawn question you would like answered. Digitial photos can be attached to your question.

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