I'm cutting lawns at 3 inches once a week but I'm noticing that when I'm done cutting the lawns look all yellow now. When I take a clump of grass in my hand, some blades are all yellow, some green. What's going on? IS it the high rate of growth from all the rain and could I be cutting into the root system? I can't cut any higher or I won't be able to keep up. We have about 60 lawn accounts. I'm putting on round 2 of fert + spraying weed control next week. Do you guys have any suggestions or hypotheses about what's going on or what I could do? Thanks!