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chrisinga

Help! I think I made a huge mistake with Image crabgrass killer

chrisinga
9 years ago

Hello everyone. I've been a lurker for awhile and finally screwed up enough to ask a few questions.

I have a small Bermuda yard that I do my best to maintain. I had it looking pretty nice up until the temp got up in the 90s. Once the temps rose, I had a terrible crab grass infestation. It was all over.

I now understand that prevention is the key. Too late for that. So I bought some Image Crab grass killer, mixed it per instructions. I guess I sprayed too much per sq ft. It killed 95% of the crabgrass in a day or two. But then with the heat my beautiful once deep green Bermuda is badly yellowed.

I was advised to keep it watered to the point where I can stick a 8 inch screw driver all the way down. I have done this every evening.

I was told not to apply some super high nitrogen fertilizer because it may damage the already weakened grass by the man at the hardware store who claimed he was an expert. I was told to put something high in nitrogen down immediately by the head golf pro at the local golf course.

Thoughts?

I called Image, they suggested applying Ironite. I did that this evening. We shall see how that goes.

I'm pretty bummed that this happened, I am in a slight competition with some neighbors and I just fell to dead last:(

How can I fix? Thanks in advance!

Comments (14)

  • chrisinga
    Original Author
    9 years ago

    Day before applying Image

  • dchall_san_antonio
    9 years ago

    Dead last??? BUMMER! Do you want to be #1? Find the Bermuda Bible online and memorize it. It's not hard. Here's a summary

    Weekly
    Mulch mow 2x at the mower's lowest or next to lowest setting
    Water once a full inch

    Monthly all season long
    Fertilize with a high N fertilizer

    I would add to his advice one thing. Make one of your fertilizer applications an organic fertilizer. When you apply a lot of chemical fertilizer, over time you can develop a problem soil. Adding organic fertilizer can stop that from happening. You can add organics as often as you want and any time of year as your budget allows.

    If you do those things you should not ever get crabgrass. I suspect you are watering more than once per week, because crabgrass seed needs continual moisture for several days in a row to germinate. If you only water once a week, it almost never germinates.

    The Bermuda Bible was written by Texas Weed, our sometimes resident bermuda expert. He is a retired sod farmer and just passed the test to be a certified USGA turf expert, so he knows his stuff. I believe he just updated the Bermuda Bible, but I don't know if the changes are posted yet.

  • chrisinga
    Original Author
    9 years ago

    I too dressed it with a mix of river sand, peanut shells, and compost about a month or so ago. I am watering every night.

    What are your thoughts on applying something like Scott's max green (if I remember correctly it was 26-0-2)
    On top of the Ironite? Too much?

  • dchall_san_antonio
    9 years ago

    Find the Bible online. You are watering exactly wrong with time of day, timing, and likely the amount. That alone might be most of your problem. You have water stressed grass and the herbicide simply added that last bit of stress. You can and will recover. Start by fixing your watering. Find the Bermuda Bible.

    Today's Ironite is nothing but fertilizer. They have changed the formulation to comply with various state and federal regulations and finally just went with fertilizer. The Bermuda Bible tells you exactly what fertilizer to use and when.

    You should never have to topdress. He never even mentions it in the Bible. Topdressing is something they do on golf courses, because they have the grass and soil so stressed that sometimes both the grass and soil become hydrophobic (sheds water). The solution they have come up with is to add a thin layer of sand which is not yet hydrophobic. Somehow that works for them. As a home owner, that should never happen for many reasons. If you feel an overpowering urge to topdress with something, leave out the sand and topsoil. Use only organic topdressing materials.

    When you mow, is your soil surface pretty smooth or is it bumpy?

  • chrisinga
    Original Author
    9 years ago

    i top dressed it to smooth out the bumps. It actually helped a lot and allowed the bermuda to spread more rapidly.

    what are your thoughts on putting down nitrogen over the ironite?

  • dchall_san_antonio
    9 years ago

    Maybe someone else will pamper you through this, but I'm getting the impression you're resisting the idea of reading the Bermuda Bible. Read the Bermuda Bible. It's about 10 paragraphs long and covers everything. I would link you directly to it here, but that would violate the terms and conditions of this forum. I've already been warned and warned. Here is a thin workaround to the T&C. I'm pretty sure the first hit is the only one that has been updated. People have copied it all over the Internet, but that's the only one he's updated as far as I know. After reading it, if you have questions about how to interpret what he says, then I would be thrilled to help you with that.

    That simple little pamphlet has practically eliminated bermuda questions from these forums. The hardest part for new readers is to forget, and completely unlearn, all the bad practices and outside advice they have gotten themselves into over the years. If it is not mentioned in that document, put it out of your mind. You've gotten yourself into a competition with your neighbors. You'll have to completely ignore them and what they are doing so you can focus on the Bermuda Bible.

    The only bermuda topic he did not cover was leveling to flatten a bumpy lawn. If you simply topdressed, then you did not level it. If you have future issues with mower scalping or bumpy soil, search this forum for "leveling bermuda." It can be a lengthy discussion and is a fairly involved process. If you follow the guidelines you'll have a putting green surface which can be mowed as low as 1/2 inch or lower. It sounds like you might be a candidate with the neighborhood rivalry going on.

  • morpheuspa (6B/7A, E. PA)
    9 years ago

    Ironite is, well, kind of useless. I wouldn't use the old stuff due to arsenic levels and apparently the new stuff is just fertilizer anyway. Fortunately, there's a cheap way of dumping iron on your lawn.

    Milorganite. Bag rate will apply around 0.6 pounds of iron per thousand square feet, which is way more than it needs. It'll provide a very light feeding as well, but that can be ignored on Bermuda (which is a nitrogen hog during summer).

    One shot should undo your chemically induced chlorosis pretty quickly, and you shouldn't need another unless you accidentally overapply it again.

  • chrisinga
    Original Author
    9 years ago

    thanks morpheuspa. ill try to find some of that on the way home.

    read the bible... it didnt answer my questions on bringing back a chemically damage lawn, or what the consequences of applying a super shot of nitrogen would do to an already damaged lawn.

  • morpheuspa (6B/7A, E. PA)
    9 years ago

    >>read the bible... it didnt answer my questions on bringing back a chemically damage lawn, or what the consequences of applying a super shot of nitrogen would do to an already damaged lawn.

    It doesn't really deal much with incidental problems (because there are so many).

    In this instance, over-application of Image caused some chlorosis. Whether it's blocking photosynthesis or chlorophyll production or iron uptake, I don't know, but the fact that the company recommended Ironite suggests it's blocking chlorophyll or iron uptake.

    Time is really the only cure for that, plus treating the symptoms. Milorganite will help with that, although it's not going to be the magic cure it can be on chlorotic lawns that aren't otherwise stressed.

    Flushing with water might help, but it takes quite a bit--usually three inches per water application, repeated several times in a reasonable time span. Three inches of water is fifteen hours with a standard oscillator (variable timings with an in-ground). Since I can't find if Image is soil binding or water soluble, whether it'll help at all is unknown.

    Super-shots of nitrogen are handled fairly well by Bermuda lawns, that I know, but there is a definite limit.

    On damaged lawn, I'd target 1 pound per thousand of nitrogen (synthetic) or slightly less and not stress it--but I'd also keep an eye on it and feed it again any time past the 2 week mark if it looks like it wants more to eat. Or, less but more often, roughly the way people eat when sick.

    I'm not a fan of excessive nitrogen on any grass at any time as that excess tends to end up in the air as an NOx compound or in the water supply, causing eutrophication in streams and lakes. I have no objection to normal amounts applied more often if the grass or gardens require it--air and water escape is far lower in that case.

    Still, there are cases where breaking that rule makes sense. A stressed lawn of any species isn't one of them, it's not going to be a super-heavy feeder at any particular instant, although to restore it feeding more often will probably be required to keep a steady flow of N into the grass and encourage it to spread into any dead areas.

    Bermuda is very happy to spread aggressively in warm weather when well-fed, so keeping a constant flow for the rest of the summer will certainly help with that.

  • yardtractor1
    9 years ago

    How much fertilizer does the Bermuda Bible suggest that should be applied in July and August? A slow release 39-0-0- or a 35-0-0 every 4-6 weeks? Then that's what you should do.

  • dchall_san_antonio
    9 years ago

    Okay, thank you for reading it. But you should have gotten an idea that bermuda is almost bulletproof. It will return even if you try to put it in its grave. It can take all the high N fertilizer you can throw at it. Normally adding more high N fertilizer to Ironite would be an easy yes answer.

    Milorganite will be absolutely harmless to the bermuda. It will be extremely effective, but you can be sure it will not do any further damage.

    I disagree that adding topdressing allows bermuda to spread faster. I just trimmed 4 feet of bermuda runners off my asphalt driveway. Bermuda is going to spread no matter what. I think the topdressing simply allows you to see the runners.

    And if you read about watering then you'll realize you should be watering in the morning and about once per week instead of every night. Bermuda is fairly resistant to fungal disease, but if you wanted to know the fast track way to cause disease, it would be to water every night.

    The BB suggests watering an inch. You can test your sprinkler system to see how long it takes to get an inch by putting tuna or cat food cans out in the yard. Time how long it takes to fill all the cans. That is your target time for watering. In the summer you can set your sprinkler to water for that time once a week until the temps drop back into the 80s. Then reset it to water once every 2 weeks. The idea is to only water deep to get water down into the soil. And then by withholding water for many days at a time, the weeds and diseases which need continual moisture to get started will never be able to start. This works! In fact the whole idea of deep and infrequent watering was well argued on this forum back in 2003 or so. The winner was the lawn care professional from Phoenix - who was caring for 50 lawns all watered deep and infrequent all summer long. The loser was me - who had always gotten weeds but never knew why. I was doing what my father did and what the sprinkler installers told me to do. Now I have very few weeds in my St Augustine. Even the nutgrass is gone.

    If you follow the bermuda bible there's no reason why you should not have the best lawn in the hood. I participate in another forum with many more bermuda fanatics. They have incredible, putting green lawns, and they follow the bible.

  • chrisinga
    Original Author
    9 years ago

    thanks for all your help! i have applied Ironite and Milorganite. I will cut my watering back and start doing it in mornings. I am going to give it a week or so, then give it some high nitrogen.

    One last question... on mowing.

    What are the consequences/benefits of mowing it right now. I was mowing every 3-4 days to 1 inch with a reel mower. I havent mowed in about a week and half now.

    im debating on a few options:

    1. My neighbor basically scalped his whole yard on accident last week, granted it was always cut short and looked nearly perfect before. this week it greened back up and you cant tell. Would scalping and bagging the clippings help or hurt at this point? I figure it would essentially be starting over.

    2. the exact opposite. Letting it grow and maintain it at 2-2.5'' until it greens back up

    3. Continue mowing at 1'' every few days like nothing has happened.

  • chrisinga
    Original Author
    9 years ago

    For all who care, this is what it looked like last summer. Very patchy, builder laid dormant sod, and it's didn't take well. It has come a long way since last summer.

  • dchall_san_antonio
    9 years ago

    Gosh time flies on this forum especially in bermuda-years. This drifted down to page 2. You've probably mowed 3 times since your last post.

    What did you do and how does it look now?

    Have you changed your watering?

    Did you fertilize yet?