Registration of 'NuStar' Kentucky bluegrass.
Released in 1991 and originating as a single plant selection from an apomictic Poa pratensis individual found growing near Ritzville, Washington, this turf-type variety (PI561038) has an apomixis rate under spaced plant conditions of over 85%. It produces a dense, moderately dark green turf with good early greening in spring and good winter colour. At New Brunswick, New Jersey, it ranked fourth of 59 varieties in overall turf quality. NuStar has resistance to Erysiphe graminis and Magnaporthe poae in test trials in Idaho and New Jersey, respectively. In national testing, NuStar was resistant to Drechslera poae, Laetisaria fuciformis, Leptosphaeria korrae, Lanzia spp. and Moellerodiscus spp. and Pythium aphanidermatum. NuStar has intermediate resistance to drought dormancy, resistance to drought wilting and recovery from drought. It has also shown good resistance to frost damage and intermediate resistance to Poa annua encroachment. Moreover, it has high seed yield potential and is free of Claviceps purpurea. NuStar is recommended for lawns, recreational turf, golf courses, parks and low maintenance sites in areas where P. pratensis is well adapted for turf. NuStar is compatible in blends with most other conspecific varieties and in mixtures with improved turf-type Lolium perenne, Festuca rubra and F. arundinacea varieties. When used in mixtures with other species, it performs best in ratios of over 75% P. pratensis.