did some practical experimentation. I plan on doing more. As of yet, I haven't finished the research on my options.
First, we have a big crabgrass problem at one of my school gardens. It is so bad that during the heat wave we had here in Jersey about 10 days ago, the crabgrass took over some of the beds. My solution is what I described to you above, which is effective with not much work plus it's inexpensive. However, this solution only works in some instances, as you have told me your town would give you some grief over it.
Similarly, I have one bed which my science students planted that has their plants in it, interspersed with crabgrass that has tenaciously taken over (I might get a pic), and I cannot use any means other than pulling it. I did that and let me tell you, it was tough. It was so difficult that I had to put the sprinkler on it to loosen the roots. That helped, but it still wasn't a cream puff job.
At the same time I was doing this, one of the male gardeners stopped to observe and said watch me.
He went to an open bed that had been taken over by crabgrass, got the mattock out of the shed, and in about six swings had the entire ground broken up to where the crabgrass could be picked up an thrown in a bin for disposal. I was impressed!!
What this says to me is that if you want a lasting solution, you could divide this job up and do half one day, have the guy clean it by raking, making sure nothing is left in the ground, and then proceed with lawn seed. If it works, then move on to the second half. You will have to baby it for a time, meaning water it, etc., but in the long run, it will behave like the other grass and you won't have this aggressive patch growing.
One thing for sure, I doubt people like you and me could swing the mattock that way, but some guy could.
More tomorrow, when I get the research on my other solution. I am having a blast with this second solution, but I know you won't like it.
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