Empirical modeling helps understand decay processes. The objective of this research was to find a suitable model, and then use it to describe decay of thatch from hybrid bermudagrass [Cynodon dactylon (L.) Pers. × Cynodon transvaalensis Burtt‐Davy]. The carbon dioxide–carbon released from ‘Tifdwarf’ and ‘Tifeagle’, each 24 h over 20 d, was plotted as percent C remaining vs. time. Four empirical models were fit to these data to determine which one best minimized residual sum of squares. The model best meeting this condition was the four‐parameter double exponential model. Of the models tested, it was the only one to pass all tests for normally distributed population, constant variance, and independence of residuals. Fitting this model to percent C remaining data identified two C pools for each cultivar, a fast pool and a slow pool, with differing sizes and rate constants. Fast‐pool turnover times were similar. Slow‐pool turnover times differed, with Tifdwarf decaying faster than Tifeagle, which may have been a function of Tifeagle having a higher stolon mass with more lignin and a wider C:N. When data were corrected for microbial growth efficiency, slow‐pool turnover times decreased. This implied cultural practices that increase microbial growth efficiency may help convert slow pool into biomass, reduce slow‐pool turnover times, and ultimately enhance the decay of thatch.

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Biological production of sulfide (S2-) in soil has been reported to depend on system redox potential and on the concentrations of available sulfate (\batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{SO}_{4}^{2-}\) \end{document}) and organic carbon (OC). The purpose of this laboratory study was to determine whether elemental sulfur (So) could influence redox potential and S2- production in sand used to construct putting greens. Treatment with So depressed redox potential as pe + pH, and stimulated accumulation of both free H2S and acid-soluble S2-. Organic carbon as lactate (C3H5O3Na) intensified the effects of So, primarily by influencing pH. Thus, So application could induce anaerobiosis and subsequently affect turf quality by heightening production of free hydrogen sulfide (H2S). It could also contribute to S2- accumulation possibly expressed as a black layer or blackening of the root zone.

Synthetic hydraulic fluid, which was developed for turf equipment in 2005, was compared to traditional hydraulic oils for its potential to cause turf injury. Effects of fluid type, volume, and temperature on area of injury, percent necrosis, and time to healing were investigated at Edison College in 2005‐2006 via three experiments on hybrid bermudagrass (Cynodon dactylon L. [Pers.] × C. transvaalensis Burtt‐Davey) or seashore paspalum (Paspalum vaginatum O. Swartz). Synthetic fluid applied on container‐grown ‘Tifeagle’ at 1.85 ml/cm2 caused minimal shoot necrosis that healed within 10 days, while hydraulic oils caused 100% necrosis of shoots. Synthetic fluid applied on putting greens in the field at a volume of 20 ml caused an average of 70 cm2 of injury with 17% necrosis after 5 days. Time to healing was 15 to 30 days. In contrast, hydraulic oils caused larger areas of injury with more necrosis and longer healing times. Increasing volume increased injury area for all fluids tested, but temperature had minimal effect. Increasing volume and temperature increased percent necrosis for synthetic fluid but not for hydraulic oils. Compared to hydraulic oils, synthetic fluid consistently caused less injury to warm‐season turfgrasses and is a viable replacement for traditional hydraulic oil in turf management equipment.

Irrigating salt-tolerant grasses with nonpotable water, like salt water, conserves fresh water resources. Advertising suggests that ‘SeaDwarf’ seashore paspalum (Paspalum vaginatum O. Swartz) is salt-tolerant and that it resists the effects of salinity on growth typically observed when irrigating other turf types with salty water. As a result, it is now being used on golf courses and home lawns in an effort to help conserve fresh water. Commensurate with the use of nonpotable irrigation, however, would be an expectation of high turf quality. This study was done to determine if the quality of ‘SeaDwarf’ seashore paspalum was affected by irrigating it with nonpotable water having high levels of salinity. Seven irrigation water sources created by blending tap water and ocean water and ranging in salinity from 0.52 to 49.40 dS·m−1 were used to flood-irrigate containerized ‘SeaDwarf’ seashore paspalum once daily for 50 consecutive days. Turf quality gradually decreased as salinity increased but improved with time except at the highest level of salinity. Effect of water source on turf quality was attributed to salinity-induced changes in quality parameters, including leaf texture, color, stolon growth, and shoot yield. The observed effect of salinity on quality parameters likely resulted from osmotic stress associated with high levels of salinity. The salt tolerance of ‘SeaDwarf’ seashore paspalum in this study was moderately good, but irrigating it with water having lower levels of salinity resulted in better quality turf.