Effects of rootzone composition and irrigation regime on performance of velvet bentgrass putting greens. I. Turf quality, soil water repellency and nutrient leaching

Abstract

The use of velvet bentgrass (Agrostis canina L.) on putting greens is limited by sparse knowledge on optimal maintenance. The objectives of this study were to determine the effects of rootzone composition (SS, straight sand; or GM, sand amended with 20% v/v garden compost) and irrigation regime (LF, light and frequent; or DI, deep and infrequent) on turfgrass visual quality, soil water repellency and nutrient leaching. The study was conducted from August 2007 to October 2009 on an experimental USGA green seeded in June 2007 with velvet bentgrass ‘Legendary’ at a coastal location in Norway (Landvik, 58° N). Better turf performance on GM than on SS was associated with less water repellency at most investigated depths in the 10-cm top layer, 88% lower nitrogen loss in the form of nitrate/nitrite during the first year after sowing, less injury caused by Microdochium nivale, and quicker recovery during both spring periods. A decrease in turf visual quality on SS receiving light and frequent irrigation in the second year was associated with strong water repellency in the mat layer. Compared with light and frequent irrigation, deep and infrequent irrigation resulted in better turf quality and lower drainage volumes.