Getting rid of undesirable grass
On our large lawn, we have a bad section of grass, that I believe may be bentgrass. It started in small patches maybe 4 years ago and has spread in this section. It is light colored and ugly until sometime in May, when it starts to green up and look better.
How do I get rid of it so that it won't come back? If I kill it, remove it and replace it with sod, what can I do so as not to get it back again?
Utah County Utah
Unfortunately, controlling perennial grass weeds in a perennial grass area is one of the more challenging "weed" issues there is in lawn management. To get rid of the "undesirable" grass, you will do best by spraying out the area with a non-selective herbicide such as RoundUp or Finale. Note that this may take several sprays to get complete kill.
Once that is accomplished, sodding the area will give you the best chance at keeping the undesirable grass out. You'll want to be sure that you water the new sod adequately while it's establishing and getting rooted into the native soil. In the longer term, you'll want to follow good basic management practices in order to keep your lawn dense, healthy and competitive against weeds.