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Warm-season turfgrasses differ widely in their tolerance to low light. Shade conditions, as the result of shrub or tree presence, are greatly influenced depending on whether the tree or shrub is deciduous or evergreen in nature. The purpose of this study was to determine the influence of deciduous shade on the quality and yield of four major warm season lawngrasses. Zoysiagrass (Zoysia japonica (Stued.) X Z. tenuifolia (Willd.) 'Emerald'], St. Augustinegrass (Stenotaphrum secundatum (Walt.) Kuntze] 'Fioratam' and 'Floratine', and centipedegrass (Eremochloa ophiuroides (Munro.) (Hack.) 'Oklawn'] were sodded in outdoor plots on an Olivier silt loam (finesilty, mixed, thermic aquic, Fragiudalf) soil. All were exposed to unshaded and 47 and 63% shade regimes of green saran screening for 7 months each year to simulate Gulf South deciduous shade tree conditions. Determination of lawngrass quality and yield responses were made for 3 yr. Increased shade decreased air temperature at sod level. Mean air temperature at sod level was not correlated with quality of any lawngrass. Mean air temperature at sod level was significantly correlated only with clipping yields of Floratam St. Augustinegrass and Oklawn centipedegrass. Lawngrass quality generally decreased with increasing shade. Photon flux density was significantly correlated with quality of alllawngrasses except Oklawn. Quality ratings in 63% shade indicate that Floratam St. Augustinegrass quality was most intolerant, while Oklawn centipedegrass quality was most tolerant of reduced light conditions. Quality and yield were not significantly correlated in any lawngrass. Lawngrass yield generally decreased with increasing shade. Emerald Zoysiagrass mean clipping yields were least reduced, and Floratam St. Augustinegrass mean yields were most reduced in 63% shade treatments.Additional index words: Shade tolerance, Eremochloa ophiuroides (Munro.) (Hack.) Stenotaphrum secundatum (Walt.) Kuntze, Zoysia japonica (Stued.) X Z. tenuifolia (Willd.).

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Effects of 16 nitrogen treatments were compared in 1974, 1975 and 1976 on a United States Golf Association (USGA) golf green planted with ‘Tifgreen’ Bermudagrass (Cynodon dactylon (L.) Pers × C. transvaalensis). Activated sewage sludge (Milorganite) was superior to ammonium nitrate and ureaformaldehyde (Uramite) at most rates and application frequencies. The best quality (by panel evaluation) turfgrass resulted from 1.80 kg per 92.9 m2 of Milorganite N applied monthly (May to November) or bimonthly applications of 5.40 kg. Biweekly applications of 0.45 or 0.90 kg of ammonium nitrate N ranked next, but monthly applications of 0.45 to 1.35 kg failed to provide acceptable turfgrass quality. Ureaformaldehyde N at monthly rates from 0.45 to 1.80 kg was inferior to other sources at the same rates and application frequencies. Foliar concentrations of N, P, K, Cu and Zn above critical levels were associated with increased quality and yield. Tissue Mg, S, Fe and Mn content had no influence on turf quality or yield. Foliage micronutrient levels were generally higher than previously reported by other workers.