I have a 3 acre grass area used for recreation north of Rice Lake Wi. I have resisted chemical treatments to save bees and butterfles. Also have not fertilized. The area is now half weeds and quack grass is taking over. I have always thought quack grass to be only killed by round up or total kill products. Am I correct in this thought? Lawn experts are recommending treating with some Q product to help, is it going to kill quack grass? Also a lot of fungus on wet years, perhaps fusarium blight in the remaining bluegrass. Suggestions?
Washburn County Wisconsin
I don't know of any products that selectively kill quackgrass and not other grasses, but it's possible that something like that exists (if so, it is likely available only to professionals and not homeowners). Once quackgrass invades a lawn, there isn't much you can do to eliminate it, short of spraying everything with a non-selective herbicide (such as RoundUp) and starting over. As for the other weeds, broadleaf herbicides are about the only practical control method on 3 acres. I too, prefer to not use pesticides unless necessary, and find that a single application in the fall every other year is a good compromise as it keeps the weeds from taking over too much (doesn't eliminate them entirely) but we're not treating all the time. Fertilizing is a good idea, as this helps the bluegrass remain healthy and better able to outcompete the weeds. See http://hort.uwex.edu/ for more info on lawn care.
As for the disease issue, your best bet it to contact the O. J. Noer Turf Research Facility (http://ojnoer.ars.wisc.edu/) or the UW Turf Diagnotic Lab (http://labs.russell.wisc.edu/tdl/).