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Turfgrasses benefit the environment through conversion of CO2 into stable C stored in soils. Limited research on the sequestration potential of bermudagrass (Cynodon spp.) has been conducted in semiarid climates. The objective of this study was to evaluate soil physiochemical properties of golf courses in Lubbock, TX, to determine C sequestration potential and longevity. Soil was obtained from fairways of five golf courses ranging in age from 13 to 93 yr. Shallow (0–7.5 cm) and deeper (7.5–15 cm) soil depths were tested for soil pH, electrical conductivity, soil organic matter, soil organic C (SOC), inorganic C, total N, inorganic N, and texture. After ANOVA and mean separation, principal component analysis (PCA) was used to group golf courses by soil depth or age. Soil organic matter and SOC decreased with depth, but the rate of SOC accumulation (0.22 Mg C ha−1 yr−1) was lower when compared with previous studies. Maximal C (35.1 and 23.7 Mg C ha−1 in the upper and lower depths) was consistent with previous studies, indicating that C accumulated for a longer period of time. The PCA explained 52.7% of variability in soil physiochemical properties on two axes, but PCA more effectively differentiated soil sampling depth than golf course age. High variability in data among fairways at a single golf course likely resulted in limited grouping capabilities. Including a broader regional representation of golf courses or sampling golf courses between 40 and 70 yr to quantify soils near maximal accumulation would strengthen future studies.

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Urban soils may restrict turfgrass rooting depth with shallow soil layers in high sand content soils, which may influence water conservation. A greenhouse study sought to quantify water usage and determine the physiological response of turfgrasses at four irrigation levels. ‘ATF-1434′ tall fescue (Schedonorus arundinaceus (Schreb.) Dumort. nom. cons.; syn. Festuca arundinacea Schreb.), ‘Jamur' Japanese lawngrass (Zoysia japonica Steud.), and ‘Zeon' Manilagrass [Zoysia matrella (L.) Merr.] were established in 10 cm (4 in) diameter by 17.8 cm (7 in) tall containers. Each species was irrigated with 16.5, 21.9, 27.3, or 32.7 mm.wk−1 (0.65, 0.86, 1.1, or 1.3 in.wk−1). Gravimetric water loss was determined by pre- and post-irrigation pot weights. Turf quality, leaf discoloration, percent green cover, and gross photosynthesis were evaluated weekly and root parameters were measured at the conclusion of each trial. Although root mass was similar among species, water deficit stress and leaf discoloration occurred sooner in tall fescue than the two Zoysia species, reducing turf quality and green cover. Japanese lawngrass and Manilagrass had greater stomatal conductance, resulting in 109 and 89% higher gross photosynthesis relative to tall fescue. Both zoysiagrasses maintained acceptable turf quality with 27.3 mm water.wk−1. However, tall fescue quality was not acceptable at any irrigation level. Index words: Photosynthesis, gravimetric water loss, tall fescue, Japanese lawngrass, Manilagrass. Species used in this study: Tall fescue (Schedonorus arundinaceus (Schreb.) Dumort. nom. cons.; syn. Festuca arundinacea Schreb.); Japanese lawngrass (Zoysia japonica Steud.); Manilagrass [Zoysia matrella (L.) Merr.].