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April 23, 2016

Question

I would like to compost my grass clippings; how can I kill weed and grass seeds in the clippings?

 

Answer

 Some of the weed and grass seeds will be killed through the composting process by the heat that is generated while things break down.  However, a home compost bin never generates enough heat uniformly enough in the pile to get total kill.  What goes in, can come out.  That is why we don’t recommend putting heavily diseased material into a compost pile or many weed seeds.  I am sure everyone has seen a unique squash or gourd plant that starts growing out of a compost pile—same principle applies—the squash seeds didn’t all get killed either.  


 

(December 2012)

QuestionWith the crazy weather we have had this year, we have a yard full of stickers. Don't remember ever seeing them this time of the year. Would it be ok to spray them now? If yes, what would you recommend?

Answer The sticker weeds are normally here this time of year, but this year they are growing faster than normal. The sticker weed is called spurweed and it germinates in the fall, grows all winter and dies in late spring. If you already have stickers, then it is definitely ahead of schedule, since the stickers are the seeds that are produced after it blooms. Pick a mild day with little wind and spray with a broadleaf herbicide containing 2, 4-D. You don’t have to spray the entire yard, just where the weeds are. Luckily it is an annual weed, and if you can kill it before too many seeds have set it will reduce the population for next year, but if allowed to grow unchecked, you will have more and more stickers each year.


(September 2012)

QuestionFor years my wife's father had his yard in primo condition. Since his passing, the yard has cultivated a dandy crop of crab grass and other weeds unknown to me. I have used Ortho Weed Killer with crabgrass preventer, and it really doesn't seem to be doing the job. In thinking ahead to spring of 2013, what would be my best option in eradicating crabgrass from the yard, and should I start this fall. I do plan to apply a Wintertime weed and feed probably in mid October.

Answer I don’t like to use any fertilizer on lawns in Arkansas after mid September unless you are growing tall fescue. Most southern lawns go dormant for the winter, and I would hate to encourage new growth, too late in the year, or spur on winter weeds. Crabgrass is a summer annual weed, which means it germinates in late spring, grows all summer, sets seeds and dies in the fall or early winter. There is nothing to do this fall to prevent it for next year. Apply a pre-emergent herbicide in late February and a second application in early April and you should be good. Monitor for weeds during the growing season. The more dense the lawn grass, the less weeds you have. We do have lawn care calendars for each of the lawn grasses grown in Arkansas on our website: http://www.arhomeandgarden.org/lawns.htm

 

QuestionFor years my wife's father had his yard in primo condition. Since his passing, the yard has cultivated a dandy crop of crab grass and other weeds unknown to me. I have used Ortho Weed Killer with crabgrass preventer, and it really doesn't seem to be doing the job. In thinking ahead to spring of 2013, what would be my best option in eradicating crabgrass from the yard, and should I start this fall. I do plan to apply a Wintertime weed and feed probably in mid October.

Answer I don’t like to use any fertilizer on lawns in Arkansas after mid September unless you are growing tall fescue. Most southern lawns go dormant for the winter, and I would hate to encourage new growth, too late in the year, or spur on winter weeds. Crabgrass is a summer annual weed, which means it germinates in late spring, grows all summer, sets seeds and dies in the fall or early winter. There is nothing to do this fall to prevent it for next year. Apply a pre-emergent herbicide in late February and a second application in early April and you should be good. Monitor for weeds during the growing season. The more dense the lawn grass, the less weeds you have. We do have lawn care calendars for each of the lawn grasses grown in Arkansas on our website: http://www.arhomeandgarden.org/lawns.htm


(June 2012)

QuestionWe used a pre-emergent herbicide on our lawn this year and it did not stop the progress of the weed called crabgrass. Is there something I can do to rid my yard of this grass?

Answer The standard herbicide for crabgrass control for years was MSMA and it is no longer on the market. We now have products that contain quinclorac for control. However most homeowner products are combined with another herbicide –many have 2,4-D (a broadleaf weed killer) which could burn warm season grasses when applied during the hot summer months –trade names include Weed-B-Gone Max, Weed Stop plus Crabgrass Killer and All in One Lawn Weed and Crabgrass Killer. Some products are combined with sulfentrazone—a sedge killer; trade names include Image Kills Crabgrass or Sedge and Grass Killer. Make sure if you are applying herbicides that you read the label beforehand. Follow recommended rates and read if there are any temperature restrictions and that it is safe for the type of lawn you are growing. Many herbicides are not recommended for use on St. Augustine or Centipede lawns. Also, make sure that the lawn has ample moisture before applying chemicals or fertilizers or you could damage the lawn. Don’t spray on a windy day and don’t treat the entire yard if you just have a patch here and there—spot spraying would be much safer.


(May 2012)

QuestionI'm hoping you can help me with a problem we are having with our grass! We live out in the country in the middle of a field. We have always had several varities of different grasses in our "yard". However, this year, what grass we have seems to have been taken over by stickers! The "grass" which is now mostly stickers is all brown and crunchy. We have lots of little white blooms of some kind (I'm assumming they are the seeds of the sticker "grass") all over our yard. Can you offer any advice as to what we can do to kill these things and save our grass? We can't even walk the dog without him getting them stuck in his paws!! Where could they have come from? Our yard is about an acre in size.

Answer Weeds of all kinds seem to be more prolific this year. The weed that produces the tiny sticker is called spurweed. I doubt you still have any blooms on it, because they were out most of the winter and are dying now. The sticker is the seed of the plant. Spurweed germinates in the fall, producing a ground-hugging plant with small parsley-like leaves. It does have a tiny white flower and then the seeds are produced which have stickers. It is a winter annual which dies back in the spring/early summer. The seeds will germinate in the fall and start all over again. A few this year, become a lot more each subsequent year if you don’t do something. For now, fertilize the grass (and water when dry) to get it high enough to buffer the seeds/stickers, so you and the dogs can walk. Next fall, either use a pre-emergent herbicide, or spray with a post-emergent herbicide with 2,4-D in it between December and February to kill the weeds before they set more seeds next spring.


(April 2012)

QuestionCan you tell me what the attached plant is? Is it family to the weeds?

Answer It is a common thistle, which is a member of the aster family. While they do have pretty flowers, the thorniness of the plant coupled with the invasive qualities of the plant make it less than desirable. I would try to get it out of your yard.

 

QuestionWhat I thought was crab grass in my yard has been identified by a yard professional as Dallas grass, which I had never heard of. Apparently, it doesn’t grow from a seed. My questions are: where does it come from and, short of digging it up, how do I get rid of it?

Answer Dallisgrass is a perennial grass. While it does bloom and set seed, which it can germinate from, it comes back from the root system each year, making it a more tenacious weed than the annual crabgrass which comes up only from seed each year. You didn’t say what type of lawngrass you are growing. If you have Bermuda or Zoysia grass, then wait until the Dallisgrass and lawn have fully greened up and treat with the same herbicides you would use to kill crabgrass—two brand names include Weed-Hoe or Weed-B-Gon Crabgrass Killer for Lawns. It may take more than one application, but you can control it.


(February 2012)

QuestionWe purchased an older home in North Little Rock that has a beautiful St. Augustine yard. It has increasingly become invaded by a clover-like weed. However, in the past year, we have tried to find a lawn care company to take care of this grass, but after several calls, we have received no takers. I don't mind performing the de-weeding services myself but I don’t know what to use. Do you have any suggestions?

Answer As you are aware, St. Augustine is a lawn grass that is quite sensitive to chemicals. There are several formulations of 2,4-D on the market that are labeled for use on Southern grasses. There will usually be a lower rate of application for St. Augustine grass. Remember, it is better to err on the side of too little versus too much. A few sample brand names include: Martin’s DeWeed Lawn Weed Killer for Southern Grasses, Trimec Southern, and Ortho Weed-B-Gon for Southern Lawns Formula II. It may take more than one application to kill your weeds, but spray lightly. If you go to our extension website, there is a lawn calendar for St. Augustine: http://www.uaex.edu/publications/PDF/FSA-6119.pdf and here is the home weed control guide: http://www.arhomeandgarden.org/lawns/Weeds/weed_control_calendar.htm


(February)

QuestionOn common Bermuda grass, what do you recommend to fertilize this time of the year?

Answer The best time to fertilize Bermuda grass is after it is fully green and growing--no sooner than mid April. Fertilizing it now, will just make your weeds grow faster.


(November/December)

QuestionI missed the chance to apply a pre-emergent herbicide this October to kill spurweed. Are there any 2.4-D combination products that are safe to use on Centipede grass? I've got Centipede and Bermuda in the problem area. If so, I understand you use it December thru March, at a time when temperatures exceed 55 degrees. Do you agree?

Answer Spurweed ( Soliva pterosperma), also called lawn burweed, stickerweed, and sandbur has become quite a nuisance in many lawns and I am happy you are preparing to kill it way before bloom time and then seed (sticker) set. There are numerous formulations of two and three-way mixes of 2,4-D, dicamba and MCPP. Make sure you read the label before purchasing that they are safe for southern grasses. Many will give reduced rates of application for Centipede and St. Augustine. You do want a fairly, calm sunny day with temperatures above 55 for best application and control. Spray once and then monitor your weed population and you may need to reapply two weeks later.


(February 2010)

QuestionMy lawn is part St. Augustine and part Bermuda grass. What is the best pre-emergence to use and what is the best fertilizer that works with both types of grass?

AnswerThe main reason to apply pre-emergent herbicides for warm season grasses by March 1 is the prevention of crabgrass. Products containing benefin, pendimethalin, or bensulide are all effective. There are numerous product names, but they usually always have crabgrass or weed prevention on the label. All too often we run into weed and feed formulations. If possible, go with a stand-alone herbicide, since Bermuda and St. Augustine will not benefit from a fertilizer application until April, so the fertilizer is more a waste or a boon to your winter weeds. As to fertility, both grasses need a slow release high nitrogen fertilizer since nitrogen is the nutrient used the most by lawns. Look for something with a higher first number and the next two smaller such as 27-3-4. Fertilize both grasses once they are totally green. St. Augustine could be happy with one or possibly two applications of fertilizer, while Bermuda grass will respond well to multiple applications, depending on how often you want to mow.


(June 2006)

QuestionLike most folks, I have a problem with nut grass, which I assume is the same thing as nutsedge. I’ve been told that even if I pull it up, nut and all, it will still come back because there are a series of other roots which will just takes its place. Is this correct? I’ve tried Roundup, Killsall, Poast, etc, but not one of these have been effective. I recently saw a bottle of Image that says it controls nutsedge. Do you know if this stuff really works? Is there another product you would recommend?

AnswerThe easiest way to control nutsedge is to move! Since most of us don’t have that option, there are things to help suppress it. Eradicating it may be another thing altogether! Nutgrass and nutsedge are one and the same. While it looks grass-like at first glance, it is actually a sedge—with triangular leaf blades. Grass specific weed killers won’t touch it—thus the Poast was ineffective. Physically removing as much as you can, nutlets and all will help, but won’t kill all the small dormant nutlets or seeds—thus you will have new plants appear. For those that come back there are some remedies. Sedgehammer (previously called Certainty) is a good sedge killer and is labeled for use on all lawn grasses. It does a great job, but heavy infestations won’t be completely eradicated in one season.


(March 2005)

QuestionWeeds are everywhere in my lawn! I seem to have some of everything in bloom it seems. I have not taken care of my lawn in a few years, but the weeds have never been so bad. Is there a reason, and what should I do to kill them now?

AnswerWinter weeds started early this year, and with warmer weather, they kick into high gear. If they are blooming, they are entering the last phase of their life cycle. Winter annual weeds germinate in the fall, grow all winter, begin blooming in late winter/early spring, set seeds and die. If you can keep them mowed to prevent seed set, that can reduce populations next winter. If you can get a move on it, and spray soon, you can still use a broadleaf weed killer with 2,4-D. The smaller the weed, the easier they are to kill. Try to avoid spraying herbicides when your lawn begins to green up. Grasses are much more sensitive during the transition period from dormancy to active growth, and again when they go from active growth to dormancy in the fall. So, use caution and spray as early in the month as possible. One of the reasons weeds may be worse in your lawn is that you haven’t been taking care of it. A thick, lush lawn tends to have less weed incidence than one that has gotten thin. If soil is exposed to sunlight, weeds take over. If you practice good maintenance this year, with proper fertilization, watering and mowing, your weed problems may lessen in time. Some people look at these early winter weed blooms as wildflowers. You know what they say “one man’s weed is another man’s wildflower!”


(February 2008)

QuestionMy good friend does have serious problems with sand spurs. I told her that I thought you said you have to treat for sand spurs in the fall of the year, but that was about all I remember. Can you give us guidance on how to rid her yard of sand spurs? I have stepped on them before and I hate them.

Answer I think you are referring to spurweed. This is the winter annual weed that is very low growing. It grows in the fall and winter, blooms with tiny white flowers in late winter to early spring, then sets the seed which is the noxious sticker. Sand spur is a summer weed which grows on a taller grassy plant with larger stickers. This is the season to control spurweed. By now, the weed should have germinated. Look closely at your lawn and if you have what looks like miniature parsley growing, spray with a broadleaf weed killer with 2, 4-D. If you can kill the weed before it blooms and sets the stickers, you should be in good shape.


(Nov. 2009)

QuestionI need to know when to apply pre-emergent to kill sticker weeds. The yard has gotten so bad when you come in the bottom of your shoes have stickers and the poor dog hates to go outside to relieve herself. Also, what should I use?

Answer I am glad you are asking now instead of spring when the stickers set. It is too late for a pre-emergent herbicide, but you can watch for the low parsley-like weed later this month or December and spray with a 2,4-D herbicide. The spurweed is a winter annual and germinates in the fall, grows all winter, blooms with tiny white flowers in late winter to early spring, then sets its seeds which are those noxious stickers before it dies for the season. Spraying in December, January or early February should do the trick.


(July 2007)

QuestionI recently purchased a home with a Bermuda lawn, but the previous owner planted violets in the flower beds and they had spread all over the lawns. How do I get rid of them without losing the grass?

Answer Wild violets are not an easy plant to kill. They have a small bulb or corm underground and multiply quite readily. Herbicides containing 2,4-D will give some control, but are best used when the weather is a bit cooler. It will take multiple applications. Spot spray heavily infested areas with a glyphosate product (Round-up) but be aware this product will kill grass as well. You could also dig them out, making sure to get the bulb along with the tops, but that is also hard work! Good luck.


(June 2005)

QuestionI am looking for advice on getting rid of nut grass. I have it in my lawn and I have St. Augustine, which is so sensitive to chemicals. The sprays I have tried are working and digging and sifting is a back breaking job. What can I use in the flower beds?

Answer Nutgrass is one of those weeds that makes moving seem like a good idea! In reality, there are a few products that can give you some control. For the lawn, there are several products labeled for use. One of the best products is Sedgehammer. With heavy infestations you may have to use more than one application. It is one of the most effective products and is safe on all lawn grasses, including St. Augustine and Centipede. The older recommendation is Image plus MSMA. While this is effective on nutsedge, you would have to use at least two applications, and it tends to burn back your lawn fairly badly. It is labeled only for Bermuda and Zoysia. In the flower beds, spot spray with Round-up, but again, it will take more than one application.


(February 2005)

QuestionMy husband was wondering if he could put out Roundup on dormant Zoysia grass to kill the weeds that have come up so far this spring????

Answer NO! Even though zoysia grass looks the most strawlike during the winter of almost any lawn grass, it has green near the soil line. Round-up or glyphosate products could do damage. The only grass that Round-up can ever be applied to in the dormant stage is Bermuda, and then only when it is good and dormant. If you have broadleaf weeds now, consider using a product containing 2,4-D.


(December 2005)

QuestionI know you said to put a pre-emerge herbicide on at this time of year for the stickers that look like carrot tops but I don't remember what kind to get.

Answer Since many winter weeds are already germinating, you may simply want to wait until January or early February and apply a post-emergent herbicide containing 2,4-D. This should kill most broadleaf weeds, including the spurweed --the sticker weed. The key is to control these winter weeds while they are young.


QuestionHELP!! About 2 weeks ago, I put out 3- 40 lb bags of Weed and Feed. It said it would kill henbit and sandburs and other weeds. Unfortunately, I did not save a bag to see exactly what all it said. Now my weeds are so beautiful and green and nothing is dead or dying. They look healthier than ever. The last two years the weeds have gotten worse and worse and I have got to nip them in the bud. But this has backfired and I have spent a lot of money and still have weeds. I saved an article out of the paper from last year from a lady who battled henbit, (even picked it all out by hand) and your advice to her was to put this stuff out in January, (which I did). I now have green weeds and nothing dying. I am beginning to not care if I have a lawn, just so I don't have weeds. I have partly St. Augustine, which in one part of lawn is so thick; I don't have a problem with weeds. In another part of the lawn there is a mixture of Bermuda and St. Augustine -- that is where the weeds are taking over. I live in the middle of a pasture on 137 acres. Years ago, when we had cows, we sprigged a hybrid Bermuda grass called Alicia. It is great for cows and hay but not for flowers or gardening. It grows 12 foot long runners and when you fertilize your flowers or garden, the Alicia grass just goes wild. So I have mostly gone to shrubs and trees around my house because I like to do other things besides battle grass. The only thing to tame the Bermuda is Round-up. Is that what I must resort to for killing the weeds?

Answer I wish you still had the bag. Many weed and feed products are a pre-emergent herbicide coupled with fertilizer. Pre-emergent herbicides are used to prevent weeds from germinating not kill those already growing. The product you applied can prevent your summer weeds -- which include sandburs and crabgrass, but won't have any impact on those winter weeds which are already growing. To prevent winter weeds you must use a PRE-emergent in November. As you noticed, you may have actually helped the winter weeds grow with that "feed" portion, which is fertilizer. For now, you can use a product containing 2,4- D -- Trimec is one such product but there are many other brand names. Look for a broad leaf weed KILLER not PREVENTOR. Be sure you find a product that says it is safe to use on St. Augustine. There is nothing that would kill Bermuda without also killing the St. Augustine. Bermuda is a much tougher lawn than St. Augustine, and if you have sun, you may want to convert—giving yourself a weed free zone of mulch between lawn and flower beds. Good luck!


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