Last week I was changing cup locations on the greens and was extremely pleased to see rooting to the bottom of the cup cutter and deeper. The cup cutter we use pulls the plug out in one 7" piece and to see roots popping out the bottom is a wonderful site. We even have rooting that deep in the poorer soils below some of our greens as evidenced in the picture of the black turf plug. By accomplishing this in the spring the turf plants are set up to better cope with the stresses of summer when roots die back instead of continuing to grow. It won't surprise me to see root depths as shallow as 1/2"-1" by the end of the summer if things really get stressful. And then the plant will do it all over again next season... Obviously the trick is to help the plant maintain as much root mass as possible during the summer. Syringing, deep/infrequent irrigation, and raising the height of cut are a few things that aid that in happening.