Last week I stumbled across something I have never seen before. The picture below shows a bentgrass/poa putting green with distinct lines spanning lengthwise across the green. I have observed dark green lines appear beneath the seams of covers shortly after removing the covers in the spring. The line in this picture is the result of a shift in grass species; the dark line is creeping bentgrass. It appears that the microclimate created directly beneath the seam of the cover allowed the bentgrass to outcompete the poa. More of these “lines” were visible on this green but not all greens on the course displayed this same response. I would be interested to know if anyone else has ever observed this before.
Graduate Research Assistant