Winter Survival of Fine-Textured Interspecific Zoysia Hybrids in the Upper Transition Zone of the USA

Fine-textured, high quality zoysiagrasses lack freezing tolerance for use in much of the transition zone of the U.S. Two fine-textured interspecific zoysiagrass hybrids, KSUZ 0802 (Z. matrella (L.) Merr. x Z. japonica Steud.) and KSUZ 1201 (Z. japonica x Z. pacifica (Goudswaard) M. Hotta & Kuroki x Z. japonica) were evaluated in the field for winter survival in Manhattan, KS USA along with standards ‘Meyer’ (Z. japonica), ‘Empire’ (Z. japonica), and ‘Zeon’ (Z. matrella). Grasses were established in the field from vegetative plugs in June 2013 and evaluated for winter survival and quality from 2014 to 2016. The low temperatures during the winters each year were -24 °C (14 Jan., 2014), -19 °C (7 Jan., 2015), and -18 °C (10 Jan., 2016), respectively. Greatest winter injury occurred in 2014 and 2015. When plots were rated in the spring, Meyer, KSUZ 0802, and KSUZ 1201 had > 90% winter survival in each year, whereas Empire and Zeon exhibited < 80% survival in 2014 and < 10% survival in 2015. Both KSUZ 0802 and KSUZ 1201 had quality that was better than Meyer on 6 of 13 rating dates. KSUZ 0802 and KSUZ 1201 are high quality, fine-textured, cold-hardy genotypes that are well suited for use in the transition zone.