Glycerin‐based nitrogen applications for turfgrass growth

Abstract

The purpose of this study was to investigate the effects of a glycerin-based nitrogen source on lateral spreading and recovery from simulated injury in both creeping bentgrass (Agrostis stolonifera L.)(CB) and Kentucky bluegrass (Poa pratensis L.)(KBG) . To evaluate the effect on lateral spreading and recovery, applications of the glycerin-based N product (glycerin + N) were compared with equal urea-N applications using N application rates of 6.1, 12.2, and 24.4 kg N ha −1 . To test the effect of the N treatments on recovery from simulated turf injury, injury was imposed on mature stands of CB and KBG by a golf course cup cutter, and recovery was tracked via digital image analysis over time. In a separate study, effects on lateral stem growth were investigated by transplanting mature plugs of CB and KBG to plots containing no existing vegetation, and digital image analysis was used to track the outward spreading of the CB and KBG plugs over time. Both studies were repeated in time across 2 yr. Compared with urea-N, the glycerin + N treatments resulted in increased turf injury recovery of CB and KBG by 43.9 and 44.7%, respectively, when applied at 24.4 kg N ha −1 . Additionally, the glycerin + N treatments resulted in increased spreading of vegetative plugs by 60.25% and 53.7%, respectively, in CB and KBG when applied at 24.4 kg N ha −1 . The glycerin+N material may be a valuable tool for turf managers for increasing the rate of recovery in CB and KBG following damage. INTRODUCTIONCreeping bentgrass (CB) (Agrostis stolonifera L.) and Kentucky bluegrass (KBG) (Poa pratensis L.) are two economically important cool-season turfgrass species. Creeping bentgrass is typically used for the game of golf, where it can be found anywhere from putting greens to tee boxes and fairways (Christians et al., 2017). Creeping bentgrass does well in these situations because it tolerates low mowing heights extremely well and provides a uniform surface that works well for the game of golf (Beard, 2001). Kentucky bluegrass is used for athletic fields that serve as the playing surface for sports such as football, lacrosse, soccer, field hockey, and Abbreviations: CB, Creeping bentgrass; KBG, Kentucky bluegrass.