Weeds - Crab Grass
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  (January) We live in Sherwood, Which means my yard is clay and rock. We purchased the house new 6 years ago. The yard was sodded with Bermuda grass. I would like to over seed it with Bermuda seed, but have developed a problem with crabgrass. I need to put a pre emergent fertilizer on. If I do when do I put the seed down?

  My suggestion would be to use a pre-emergent herbicide (crabgrass prevention) in mid Feb to early March. Using this will preclude you from using grass seed, since the chemical would inhibit germination of the grass seed just like it would the crabgrass. However, if you get the crabgrass under control, you should be able to really push the existing Bermuda grass with nitrogen, and get it much thicker in one season. Fertilize with a slow release high nitrogen fertilizer once the grass has completely greened up, and then reapply two or three more times throughout the season. Bermuda grass responds very well to nitrogen -- so well, you may mow more than you want to.

  (January) I had a bumper crop of crabgrass in my front yard last year that I don't want to return. I put a pre-emerge on it in the late winter, but it came up anyway. With the dry summer, the crabgrass grew better than my 31Fescue(shade)and common Bermuda(sun). I dragged out the MSMA and it ended up doing a better job on the fescue than on the crabgrass.  What would you suggest to take care of this problem ? Also what fertilizer regimen do you suggest for yards? With recent warm  weather...I'm seeing green weeds...can I use roundup on them and not kill surrounding grasses?

  It is easier to deal with crabgrass in warm season grasses than cool. February through March is the time to put out a pre-emergent herbicide for crabgrass, but you need to use caution around the fescue, since we often overseed it. Pre-emergent products are only recommended for well established lawns. If you had tons of crabgrass, you can do a split application of the pre-emergent, using some in February and a lighter dose in April. Any crabgrass that still makes it can be controlled with MSMA, but only on the Bermuda--it is not recommended on fescue. There are some other products that can be used on fescue, but it is usually hard on the fescue, since you are applying them during fescues toughest season--summer. If you have green in your Bermuda now, you can spot spray with Round-up, but only on Bermuda--no other lawn grass, especially fescue, which should be green and growing now. As for fertilization, fertilize Bermuda when it completely greens up--typically April or early May, then again in June and August, if you want to. Fescue is a cool season lawn and we typically fertilize in the fall and early spring, stopping with the onset of summer. You may want to get a copy of the lawn care calendars from your local county extension office, or visit our web site at www.uaex.edu.

  (April) What should I do about Bermuda grass in my flower beds? I have done just about everything but cut them with scissors and it is still gaining on me. And last is it too late to prune Bradford pear trees?

  Bermuda grass can be a troublesome weed. There are numerous grass specific herbicides on the market, such as Grass-b-gone, Over the top, Ornamec or Poast. Use them after the Bermuda has totally greened up and begun to run. Applied too early, you won't get great coverage, but applied late season, gives you dead grass, but lots of it, which is also unsightly. I would say it is too early to prune Bradford Pears. Most people plant them for their flowers in the spring, and their fall foliage. If you prune before flowering is over, you have lost the blooms. Unlike edible pears, which are pruned before flowering, ornamental fruit trees are pruned following flowering in the spring. Let them finish blooming, and then prune. The best pruning of a Bradford pear is thinning cuts within the structure of the tree---NOT topping! Thinning lightens the load and opens them up a bit. Many people do not realize how large a Bradford pear tree can grow-40 feet by 40 feet! We are seeing a lot of topping of these trees statewide, and that will simply increase the number of problems we will have with them.

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