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FAQs - Lawns - Weed Management - Summer

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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?

Crabgrass has taken over our yard. We have put down crabgrass killer and fertilizer with weed control. Nothing helps. Do you have a suggestion as to what to use?

My lawn is being overrun by nutsedge. I hate it! Is there any way to get rid of it without killing the whole lawn? I try to pull it out (it comes out easily) but there is way too much for me to keep up with it.

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.

This summer my lawn is full of mushrooms. Will this kill my grass and what can I do to stop this from happening?

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.

Crabgrass has taken over our yard. We have put down crabgrass killer and fertilizer with weed control. Nothing helps. Do you have a suggestion as to what to use?

There are herbicides labeled for postemergent crabgrass control available but are only effective on young plants. Since crabgrass is a summer annual, the best way to control it is to apply a granular, preemergent crabgrass control product in the spring.  Applying crabgrass preventer too early and too much spring rain are reasons why crabgrass can be a problem even though a preemergent was applied. For season long control two applications may be necessary. Make the first application when forsythia is blooming than again about 6 weeks later. Check the label of the product you select for information. Choose a product that does not contain nitrogen fertilizer. Proper mowing height (3 inches) and thickening up your lawn by overseeding in September also helps to reduce crabgrass problems.

My lawn is being overrun by nutsedge. I hate it! Is there any way to get rid of it without killing the whole lawn? I try to pull it out (it comes out easily) but there is way too much for me to keep up with it.

Nutsedge is a very difficult weed to control. The problem with hand pulling is that even though it comes out easily you leave the little bulblets attached to the roots and it keeps coming back.  This is a weed that is associated with wet, poorly drained areas but can move into areas of well-drained soil. In the long run, improving the drainage or redirecting the water so that the soil drains better will help reduce this weed. This is not a broadleaf or grassy weed but a sedge, there are specific herbicides labeled to control this weed. They contain the active ingredient halosulfuron or sulfentrazone. You can also hire a lawn service that has access to these herbicides to control this weed.   

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. Another alternative is leaving the clover (a much better option for your puppy) or control weeds and reseed areas of your yard in sections. Fence off the treated areas and then reseed. You will need to keep the puppy off the reseeded areas anyway until the grass becomes established. You can also contact the National Pesticide Information Center for information on using herbicides around pets, http://npic.orst.edu

This summer my lawn is full of mushrooms. Will this kill my grass and what can I do to stop this from happening?

A mushroom is the spore-bearing or fruiting structure of a fungus. Fungi feed on dead organic matter such as dead tree roots, buried logs and stumps. These fungi may live for many years until the wood is completely decomposed. Mushrooms cause no harm to a lawn.  There is no practical or permanent way to eliminate them. If mushrooms must be removed, simply rake them up as they appear.

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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