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The present study was conducted to explore the spatiotemporal relationship between several plant and soil properties on two natural turfgrass sports fields comprised of native and sand-capped soils before and after irrigation. Minimal differences in strength of relationship and spatical variability among field properties occurred from before to after irrigation at both fields. A number of significant relationships between field properties were observed overall, although significance did not always result in comparable spatial distributions. Additionally, significant relationships on the native soil field were not always significant on the sand-capped field. Results exemplify that a single, typical irrigation event will not noticeably change the strength of relationship or spatial distribution between field properties. Furthermore, the strength of relationship and its influence on spatial variability between field properties can be site-specific, and soil type plays an important role in this phenomenon. This information is valuable to conduct precision turfgrass management practices for potential improvement in the uniformity of multiple field properties, and also to aid in efficient subsequent sampling for future spatial map creation. [ABSTRACT FROM AUTHOR]

Natural turfgrass sports field properties exhibit within-field variations due to foot traffic from play, field construction, management, and weather. Little is known about the influences these variations may have on athletes' perceptions of field playability and injury risk. Information regarding athletes' perceptions of within-field variability could be fundamental for identifying key surface properties important to athletes, which may also be useful for the progression and implementation of Precision Turfgrass Management on sports fields. A case study using mixed methods was conducted on a recreational-level turfgrass sports field to better understand athletes' perceptions of within-field variability. Geo-referenced normalized difference vegetation index, surface hardness, and turfgrass shear strength data were obtained to create hot spot maps for identification of significant within-field variations. Walking interviews were conducted in situ with 25 male and female collegiate Club Sports rugby and ultimate frisbee athletes to develop knowledge about athletes' perceptions of within-field variability. Field data, hot spot maps, and walking interview responses were triangulated to explore, compare, and validate findings. Athletes' perceptions of within-field variability generally corresponded with measured surface properties. Athletes perceived within-field variations of turfgrass coverage and surface evenness to be most important. They expressed awareness of potential influences the variations could have, but not all athletes made behavior changes. Those who reported changing did so with regard to athletic maneuvers and/or strategy, primarily for safety or context of play. Spatial maps of surface properties that athletes identified could be used for Precision Turfgrass Management to potentially improve perceptions by mitigating within-field variability. [ABSTRACT FROM AUTHOR]

Slow growth and establishment rate has become a major limitation to the increased use of zoysiagrass (Zoysia spp.) as a turfgrass surface. Two separate field studies were conducted to evaluate the effect of genotype, planting date, and plug spacing on zoysiagrass establishment. Field experiments were conducted in 2007 and 2008 to quantify the establishment rate of six zoysiagrass genotypes from vegetative plugs. 'Meyer' exhibited the largest plug diameter (22 cm) 6 weeks after planting (WAP). in contrast, 'Diamond' exhibited the smallest plug diameter (13 cm) 6 WAP. A similar trend was observed 12 WAP. 'Meyer', 'Zorro', and 'Shadow Turf' exhibited the largest plug diameters (60, 58, and 57 cm, respectively) 12 WAP. In contrast, 'Emerald' and 'Diamond' exhibited the smallest plug diameters (41 and 40 cm, respectively) 12 WAP. Although statistically different, all zoysiagrass genotypes reached similar establishment 18 WAP indicating that plugging these genotypes in a comparable environment and using techniques described in this research may result in analogous long-term (18 weeks) establishment. Field experiments were conducted in 2006 and 2007 to determine the optimum planting date and plug spacing of 'Shadow Turf' zoysiagrass. 'Shadow Turf' zoysiagrass plugs planted on 28 July 2006 (11% to 65% cover) and 14 June 2007 (5% to 39% cover) exhibited the greatest increase in turfgrass cover 6 WAP, except for plugs planted 15.2 cm apart on 26 May 2006 (74% cover). Zoysiagrass cover was greatest for plugs planted on 26 May 2006 (63% to 100%) and 17 May 2007 (46% to 97%) 16 WAP regardless of plug spacing. These planting dates corresponded to the highest accumulative growing degree-days (GDD) experienced by all planting dates in both years. Plugs planted on 15.2-cm centers exhibited the greatest zoysiagrass cover 6 and 16 WAP regardless of planting date. Using late spring/early summer planting dates and 15.2- to 30.5-cm plug spacings may result in the quickest turfgrass cover when establishing 'Shadow Turf' zoysiagrass from plugs. [ABSTRACT FROM AUTHOR]

Establishing turfgrass in shaded environments can create a unique maintenance challenge. Shading reduces zoysiagrass (Zoysia spp.) photosynthesis and results in reduced turfgrass aesthetic quality. Zoysiagrass is a warm-season, perennial turfgrass that forms a dense, uniform turf through the production of rhizomes and stolons. It has demonstrated good tolerance to growth in reduced light intensity environments. Greenhouse experiments were conducted in 2006 and 2007 to evaluate the relative difference in growth response to three light intensities (0%, 50%, and 90% shade) among six zoysiagrass genotypes under artificial shade conditions. Percent change in zoysiagrass plug diameter decreased as shade level increased 6 and 12 weeks after planting (WAP) regardless of year or genotype. 'Diamond' and 'Shadow Turf' exhibited the greatest percent change in plug diameter 12 WAP (60% to 69%) followed by the remaining zoysiagrass genotypes (21% to 56%) when grown under 50% shade, regardless of year. In 2006, no zoysiagrass genotype maintained acceptable turfgrass quality (6 or greater) 12 WAP when grown under 50% shade. However, 'Diamond' and 'Shadow Turf' exhibited acceptable turfgrass quality ratings (7.0 and 6.3) 12 WAP in 2007, whereas all other genotypes exhibited unacceptable turfgrass quality ratings (5.0 to 5.7). In 2006, 'Shadow Turf' zoysiagrass exhibited the greatest percent increase in plug diameter (21%) followed by 'DALZ 0501' (15%) and 'Diamond' (5%) 12 WAP when grown under 90% shade. All other zoysiagrass genotypes exhibited decreases in plug diameter (31% to 87%). In 2007, 'Shadow Turf' and 'Diamond' exhibited the greatest percent change in plug diameter (11%) followed by 'DALZ 0501' (7%) 12 WAP when grown under 90% shade. All other zoysiagrass genotypes exhibited decreases in plug diameter (17% to 38%). Turfgrass quality declined as shade level increased 6 and 12 WAP regardless of year or genotype. 'Shadow Turf' and 'Diamond' exhibited the highest turfgrass quality ratings (4.7 and 3.7, respectively, in 2006 and 5.3 in 2007) 12 WAP when grown under 90% shade. Proper zoysiagrass cultivar selection may improve turfgrass growth and quality under low light intensity while increasing turf grass options for shaded environments. [ABSTRACT FROM AUTHOR]

Anecdotal evidence suggests that dallisgrass (Paspalurn dilataturn Poir.) and bahiagrass (Paspalum notatum Fluegge), two of the most troublesome weed species in managed turfgrass, are both drought and flood tolerant. Water table depth gradient tanks were employed to identify habitat specialization and competitive differences between dallisgrass and bahiagrass. Shoot and rhizome final biomass and survival were used as metrics for plants grown in monoculture or competition with hybrid bermudagrass (Cynodon transvaalensis Burtt Davy × C. dactylon (L.) Pers. 'Tifway 419') in sand or sandy loam soil. Shoot and rhizome growth of dallisgrass was greatest at the levels of highest soil moisture within each gradient tank regardless of soil type or competition. Percent survival of dallisgrass decreased to a low of 50% as depth to water table increased when grown as a monoculture and 12.5% when grown in competition with hybrid bermudagrass. Percent survival of bahiagrass was 100% regardless of water table depth, soil type, or competition. Shoot and rhizome growth of bahiagrass was greatest as depth to water table increased when grown in sandy loam soil. The opposite trend was observed when grown in sandy soil. Results suggest that dallisgrass may be more competitive with hybrid bermudagrass when volumetric soil moisture is high, while bahiagrass may be more competitive when volumetric soil moisture is low. [ABSTRACT FROM AUTHOR]

Dallisgrass (Paspalum dilatatum Poir.) and bahiagrass (Paspalum notatum Fluegge) are two of the most troublesome weed species in managed turfgrass. These rhizomatous, perennial grass species affect appearance, texture, and playability of turf in home lawns, golf courses, and athletic fields. The severity and prevalence of these problem species as well as the difficulty of achieving control with herbicide management alone invite the examination of their realized niches for clues to improved management tactics. The distribution of these species was evaluated in both fairways and roughs of three holes on each of two golf courses in North Carolina. Golf courses were selected based on the presence of both weed species. Individual plants were mapped using a high-precision global positioning system unit. This unit was also used to delineate between the rough and fairway height of cut as well as obtain elevation characteristics of each hole. Soil moisture and soil compaction estimates were obtained by sampling on a 9-m grid. Environmental characteristics used for Χ² analysis consisted of mowing height, soil compaction, soil moisture, and elevation. Data were subjected to X2 analysis to determine if the existing distribution of Paspalum spp. differed from an expected random distribution across all environmental factors. Bahiagrass growth and distribution was more affected by mowing height than dallisgrass. Bahiagrass was predominantly distributed in the rough, whereas dallisgrass occurred at both mowing heights. Similar responses were observed for both species with regard to soil compaction. Higher plant density for both species was observed in moderately compacted soil (40 to 60 N·m-2). Bahiagrass distribution was unaffected by soil moisture. Dallisgrass density was lower in areas with low volumetric soil water content (less than 27%). Although different from an expected uniform distribution on all six holes, the elevation with the highest Paspalum spp. density varied across holes. Results suggest that it may be possible to disadvantage Paspalum spp. in competitive interactions with desirable species through the alteration of landscape attributes. Substrate selection during construction, aeration, and mowing height may help create a landscape that discourages Paspalum spp. infestation. [ABSTRACT FROM AUTHOR]

Turfgrass managers applying aminocyclopyrachlor for annual and perennial broadleaf weed control in cool-season turfgrasses may want to reseed into treated areas. Field experiments were conducted in Georgia), Tennessee, and Texas to investigate perennial ryegrass (Lolium perenne L.) and tall fescue (Festuca arundinacea Schreb.) reseeding intervals after aminocyclopyrachlor applications. Perennial ryegrass and tall fescue establishment were similar to the non-treated control after treatments of aminocyclopyrachlor and 2,4-dichlorophenoxyacetic acid (2,4-D) + dicamba + methylchlorophenoxypropionic acid (MCPP) at 0, 2, 4, or 6 weeks before seeding. Results demonstrate that no reseeding interval is required after aminocyclopyrachlor treatment. Perennial ryegrass and tall fescue can be safely seeded immediately after aminocyclopyrachlor treatment at 39, 79, and 158 g/a.i./ha. [ABSTRACT FROM AUTHOR]