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chassis
06-22-2006, 07:07 PM
Despite all my efforts to attack crabgrass before it emerged in early spring, I still have quite more of it than I would like. I did the pre-emergent treatment(s) and it seemed to make very little difference.

One issue I think I have is that the past winter did not kill the crabgrass. It just withered a bit but came back again. Therefore I think alot of my crabgrass is more than one year old.

I used alot of post-emergent killer last year, and it killed some of it but not all. And I think it had a detrimental effect on my "good" grass. I understand that post-emergent crabgrass killer will kill good grass if applied too heavily.

So what are my options.. Pulling it out is not completely practical, although I believe it would work in smaller areas. In some patches (20' x 20') almost all the grass is crab, so pulling it or killing it would really mean starting over in that area.

Any suggestions are appreciated.

Bob NH
06-22-2006, 07:52 PM
I got a pint of Green Light brand 47% MSMA crabgrass killer at WalMart last week. It is potent stuff and a little bit goes a long way. For about $9 you can kill a 12,000 sq ft area of crabgrass. It also kills a long list of other grassy weeds.

But BEWARE! "Injury may occur to Bluegrass and Fescue." Bermuda and Zoysia are ok if well establishied. It will kill Centipede and St.Augustine.

I use it where the crabgrass is dominant and displacing everything else.

prashster
06-23-2006, 05:19 AM
Crabgrass is an annual plant. It dies in the winter. Yr plants are not one year old, but the result of seeds being sown last fall.

My advice is to plan on a year for getting rid of it, and don't look for immediate results.

From now until the fall, pull out as many plants as you can - a little at a time. Spot seed 'good grass' into the void. Crabgrass sows its seeds in the early fall. As you near the end of summer, step up the intensity. Focus on mature plants that have tufty seed pods at the tips. You want to prevent those seeds from being planted. Don't waste time on 'new' plants. They'll die on their own.

In the mid fall, overseed yr lawn with 'good' grass. Fertilize and water the heck out of it. Crabgrass doesn't thrive @ this time, so this is the best time to establish new lawn - which is ultimately the best way to prevent cgrass.

When next Spring comes, apply preemergent at precisely the right time. That time can vary by a few weeks depending on the weather that year. If you miss the window of germination, you're wasting money putting down preemergent. One good indicator of crabgrass germination is when forsithia plants drop their bright yellow blooms. So when yr driving around and seeing lots of yellow petals under yr neighbors forsithia plants, turn around, whip out the preemergent, and go Rambo on yr lawn.

chassis
06-25-2006, 01:13 PM
prashster,

Thanks I think I'll follow your regimen. I've always tried to time the pre-emergent application with forsythia, but I've done it when the yellow blooms are starting.

I do plan on core aerating and overseeding this fall, so it fits within the "grand plan". ;)