Effects of Shade on the Persistence of Cool Season Grasses to Form Turfgrass

cool season turfgrass have difficulties to grow and persist with good quality under shade in the summer. the objective of this study was to evaluate the ability and persistence of three cool season species suitable for turfgrass under different levels of shade, in the province of cordoba, argentina (33°07' lat. s, 64°14' long. o). density, cover, overall quality and dry weight of live and dead biomass were evaluated in festuca rubra l., poa trivialisl .and agrostis stolonifera l. var.palustris (huds.) farw. growing under 0, 25, 50 and 80% light reduction. the shade was produced with black plastic shading mesh. the behaviour of the turf was modified over time, with the genotype and the level of shade in which it grew (p ≤ 0.001). in all the variables there were interactions between species × time (p ≤ 0.001); shade level × time (p ≤ 0.001) and species × shade level (p ≤ 0.05). none of the varieties of the studied grasses can be used as a single genotype to form turfgrass under full sunlight. under 25% of shade, only a. tolonifera produced good quality turf as single species, surviving until the beginning of the second warm season. under 50% of light reduction, a. stolonifera is the only species that persisted two years from its establishment, with very good quality in the first year and just acceptable in the second year. at 80% of shading, a. stolonifera and p. trivialis persisted until the second early summer with acceptable quality, but only a. stolonifera survived two warm seasons.