Anaerobic problems on A4 greens

We received samples from four locations growing A4 bentgrass with black layer problems this winter. The crux of the problem in all four locations appears to be the heavy organic layer that A4 produces. All of the greens had reasonable aeration programs, but none of the locations were conducting weekly dustings with sand (10 - 50 lbs dry sand/1000 sq ft) — a practice that we hope will help address this problem. It is essential to continuously dilute organic matter…