A 3-year study was conducted to evaluate the comparative performance of zoysiagrass (Zoysia spp.) cultivars for shaded environments in which inputs are minimized. Included in the study were commercial cultivars Diamond, Cavalier, Royal, Shadow Turf, Zorro, Zeon, Jamur, Crowne, Palisades, and Meyer. In July 2006, grass plugs were planted in a shade nursery comprised of live oak trees providing 89% shade. From 2007 to 2009, turf plots were periodically evaluated for quality, density, color, vertical canopy height, and extent of lateral spread. Overall turfgrass quality was noticeably reduced by the heavily shaded environment; however, some cultivars attained acceptable levels during midsummer periods. A turf performance index (TPI) was generated for ranking the cultivars that represented the number of times an entry occurred in the top statistical group across all parameters and rating dates. ‘Royal’, ‘Zorro’, and ‘Shadow Turf’ were the cultivars ranking in the top statistical grouping most often throughout the study. The results suggest that Z. matrellas may be better adapted than Z. japonicas for heavily shaded environments where inputs are conserved.
Zoysiagrass (Zoysia spp.) grown under shade on golf courses and in home lawns is slow to recover from damage and declines in quality over time. We evaluated stolon growth and tillering of ‘Meyer’ and Chinese Common (both Z. japonica Steud.); ‘Zorro’, ‘Diamond’, and ‘Cavalier’ [all Z. matrella L. (Merr.)]; ‘Emerald’ (Z. matrella × Z. pacifica Goudsw.); and six experimental progeny from ‘Emerald’ × Z. japonica and reciprocal crosses of Z. japonica × Z. matrella under silver maple (Acer saccharinum L.) shade and in full sun in 2008 and 2009 in Manhattan, KS. A single 6-cm diameter plug was planted in the center of 1.2 m × 1.2-m plots, and data were collected weekly on the number of stolons, stolon elongation, and number of stolon branches. Tiller number was collected at the start and end of each study period, and biomass (excluding roots) was determined at the end of each season. Zoysiagrasses under an average of 76% tree shade exhibited reductions of 38% to 95% in stolon number; 9% to 70% in stolon length; 10% to 93% in stolon branching; and 56% to 98% in biomass. Seven of the 10 grasses exhibited a decline in tiller number in each experiment; none of the grasses differed from ‘Meyer’ in percentage change in tiller number under shade. ‘Emerald’, ‘Cavalier’, ‘Zorro’, and several progeny from crosses between ‘Emerald’ × Z. japonica or reciprocal crosses of Z. matrella × Z. japonica produced more, longer, or more highly branched stolons than ‘Meyer’, suggesting they may have improved recovery potential in shade.