Here is my Kentucky bluegrass lawn (2 acres) that has never gets any crabgrass preventative treatment. It is always the greenest lawn within a mile, and it is the only lawn around with NO crabgrass whatsoever year after year. I mow high (about 4 inches) with a John Deere zero-turn. Any feedback? (keep in mind that I manage my lawn differently than what Iowa State University recommends). p.s. I hope the pic came through.