Question
I live in Michigan's lower peninsula near Lansing 48867 (43 degrees north lat). I am considering replacing my 5 year old grass because it has a lot of grass (?) that is broad bladed and grows in clumps that are 8 to 20 inches across. These clumps of grass grow significantly faster than the "real" grass I planted originally and requires frequent mowing. My questions are 1) when should I kill the present lawn and with what? 2) What do I need to do after killing the old lawn and waiting the necessary time to be able to replant using "slit-seeding)? (Do I need to work up the dead grass or just go ahead and replant? I have been told that weed killer will not kill this unwanted grass (because it's a grass), so is there any other "solution" besides the rather radical one of replanting?Thank you for your help in this matter.    Dennis  

Answer
There are different types of weed killers. The weed killer you want is called ROUND-UP (active ingredience: glysophate) which will kill all plants: grass and weeds.

Spray on a calm day and watch out around flower beds, shrubs and desireable lawn grasses.

You could just spray the clumps, but if you would rather eradicate the entire lawn then you can do that also.

Once the product is dry, the plant will die within a few days and you can then cut the lawn really low (Scalp it) and then reseed.

I prefer to run the slit seeder over the lawn two times first without the seeds. this preparres the ground and removes most thatch and dead vegetation.

Rake debris off, and then use the seeds for two final runs (east/west and then repeat south/north for best result)

Round-Up is only taken in through the leaves and will not harm any plants once dry. It does not reside in the soil.

It is correct that broadleaf weed control (such as WEED-BE-GON) will not work on grass.

May I recommend that you spray the clumps and then rake these clumps out, preparre the soil where these clumps used to be only, and then seed. This is a lot less work.