Answers to Weed Control Questions

Q.Clover has taken over our front yard. Our back yard is untouched, but our front yard looks hideous. What is the quickest and easiest way to get rid of this?


You could treat it with a spray herbicide such as is sold by Ortho or other companies. These are usually formulated for use in the lawn and cause minimal damage to the grass.

Q. The area around our new home has mushroom rings. Is there anything we can do to remove them? We just had a ton of rain, and now we have even more mushrooms. Our neighbors have yet to seed their lot with grass. Is there anything we can do so they do not get our mushroom rings?

A. Fairy ring or any mushroom is usually an indicator that there is wood buried below the turf. It could be construction debris or roots. The only real way to control it is to remove the wood. On the brighter side, mushrooms will usually not affect the quality of the turf. They are more of a nuisance than a threat. Knocking the mushrooms down with a rake or your lawnmower and allowing them to dry and wither should reduce any slip hazards in your lawn.

Q. My backyard is about 35 square feet. I have just noticed moss on some of the bare patches. The moss is bright green and black, which really freaks me out. Could it be mold or something? What does it mean when moss is growing out of your grass?

A. Moss usually grows where the soil is too acidic, too wet, too shaded, too compacted, or some combination of these. Correcting the problem will eliminate the moss and allow grass to grow. Moss will change colors with its life cycle.

Q. Does any one know how to kill poison oak and poison ivy? My backyard has a natural area that I am doing a lot of work in. I have sprayed three times with two different chemical sprays and nothing.

A. Round Up will kill it. You have to be persistent. Spray, wait two weeks, and spray some more. In a shaded area, it will take longer than in the open sun. Also look for a broadleaf weed killer with 2-4D as the active ingredient.

Q. I have a yard full of "onions." I have tried Round Ip and various weed killers, and nothing works. Is there anything I can do?

A. Allium canadense contain hollow stems, are 1-3 ft. tall with smooth, waxy stems and flat leaves. They are difficult to control in established lawns because of the waxy coating that resists penetration of most herbicides.
Herbicides labeled for control:
2. TRIMEC - [msma, 2,4-d, mcpp]
There may be others, but these work. They may take multiple applications, as you have to kill the bulbs to stop re-growth. As always, read the label carefully and follow all safety precautions. You may get these at a nursery or garden center.

Q. I have noticed I have a couple of areas where crabgrass has grown. What can I do to get rid of it? I really have no clue and would like to get some input to avoid leaving bare and dead spots in my yard. How can crabgrass be prevented?

A. Applying a pre-emergent herbicide for the crabgrass will keep it from germinating. The existing crabgrass responds well to being pulled. Crabgrass is an annual problem, but it usually only occurs when there is bare earth exposed for it to germinate in. Seeds can lay dormant in the soils for a few years and will germinate when light and moisture conditions are right. Maintaining a dense, healthy stand of turf will prevent the seeds from germinating. If you can eliminate the crabgrass by cultivation or pull it out before it has gone to seed, you will have gone a long way to lessening the problem in the following seasons. Chemicals such as Dacthal are pre-emergent and will prevent desired grass seeds from germinating. Pre- or post-emergent chemicals controls such as those found in Dimension(TM) will also affect desired grasses. Corn gluten has shown good results as a pre-emergent or it can act as a fertilizer, but has to be applied at the right time. It also has to be used very heavily to be effective.

Q. I just purchased my first home and I am re-landscaping my garden, flowerbeds, etc. I bought my home in December so I didn't know my yard was infested with Creeping Charlie. How do I get rid of this annoying weed?

A. Creeping Charlie is a perennial, which will root at every leaf node, so irradiation without chemicals will be tough. It can be intermediately affected by 2,4-D and Mecoprop, meaning it will likely take more than one application to control it, and susceptible to dicamba. Killex is a combination of these three herbicides, so you should have some luck with it. Killex will affect all broad-leaved plants, so do not apply it in your garden with a sprayer. You can paint it on the Creeping Charlie with an artist's brush - that way you won't get drift to desirable plants.

Pay particular attention to the mixing rates and weather, as it will affect Kentucky bluegrass if over applied or applied when the weather is too hot or dry. June or September are the best times to apply the herbicide, but it may require multiple applications to be effective.

For flowerbeds, a good hoe or cultivator will be a lot more labor intensive, but probably as effective, if you are diligent. There are a few 'weeds' that will be persistent no matter what you do and unfortunately, Creeping Charlie is one of them. You could soak the affected areas with water for a few hours the day before digging the plants out. That is easier if you want to avoid chemicals, but it will come back if you don't get all the fine roots.

As always, take precautions when using chemicals. When using any chemicals, be sure to read and follow the label carefully, paying particular attention to mixing instructions and cautions; be mindful of wind conditions to avoid drift. Keep children, pets and bystanders clear while spraying; wear personal protective equipment including long pants and a long-sleeved shirt, gloves, boots and eye and respiration protection. Clean your sprayer and store it and chemicals properly, dispose of used chemical containers in a responsible manner, triple rinsing and puncturing before discarding. Do not smoke, eat or drink while spraying and wash up promptly after you finish.

Q. Should I sod over common purslane? I have tried to kill this, but it keeps coming back. What should I do?

A. Common purslane is a prolific seeder; it generates seeds so quickly that you must have so many in your yard it is impossible to keep up with it. You might try using a pre-emergent.

Q. I'm using Ortho Weed B Gone crabgrass killer. Like most herbicides, it says I can reapply in five to seven days. I sprayed this morning, and will spray again tonight. I might re-spray some areas I've already gotten. What kind of effect, if any, will this have?

A. Overlap as a result of spraying only part of your area, then returning to finish the job will usually not increase or decrease efficacy. Normally, you should wait the prescribed time before re-applying, but in your case, it shouldn't make much difference (other than your time and the few cents for the chemical used in the double dose). Depending on temperature and other conditions, it will often take at least five to seven days or longer to see results from the initial application. Re-applying before you know the application is effective is usually a waste of time and effort. Normally, you would use a second application to knock down persistent weeds or newly germinating seeds. Roundup is non-selective, so will affect most green plant material. Crabgrass killer is often most effective before the weeds have gone to seed - some anecdotal evidence suggests that many weed seeds will continue to develop and mature even after the parent plant is dead.

Applying at the lowest effective dose and spot spraying instead of a blanket application is not only the most politically correct
solution in today's' environmentally conscious society, but will often save you a lot of time, effort and money.

Q. My yard is becoming overrun by bamboo and I need a way of getting rid of it.

A. Bamboo is an aggressively invasive plant. There are a couple of approaches to eliminating it. You can dig it out. This means every single bit of it. Dense stands may require a backhoe. Even then, any pieces left will sprout. You can cut it back to the ground. With either approach, any bamboo left will need to be sprayed with a general herbicide, such as Round Up. Any new growth will need to be sprayed when it appears. Isolated sprouts may be painted with Round Up. Clumping bamboo is not as aggressive as the running bamboo.

Diligence and persistence are required to defeat this pest. If the plant exists in an inaccessible location, such as your neighbor's yard, an underground barrier will need to be installed to stop its spread. The barrier should be copper, stainless steel, or concrete at least three feet deep.

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