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Improving shade tolerance is critical for development of new turfgrass cultivars in the United States. Comparing turfgrass coverage under reduced sun exposure is a popular and effective method for determining shade tolerance, but requires years to evaluate. The objectives were to (i) compare phenotypical differences of experimental genotypes and cultivars of bermudagrass (Cynodon spp.), St. Augustinegrass (Stenotaphrum secundatum), and zoysiagrass (Zoysia spp.) grown under 73% shade and (ii) identify whether genetic improvement for shade adaptation was made in these species. This 3‐year study conducted in Tifton, GA, found phenotypic differences among genotypes within species for turfgrass coverage when exposed to 73% shade. The experimental bermudagrass, 11‐T‐56, possessed the superior combination of high green turfgrass coverage, low canopy height, and season long dark green color under shade. Experimental genotypes in St. Augustinegrass exhibited genetic improvement compared to commercially available cultivars; however, these genotypes should be examined under more intense shade to elicit differences before further selection. Performance of experimental zoysiagrass genotypes from several turfgrass breeding programs did not indicate significant improvement in the shade persistence within Zoysia spp. There appears to be genetic differences in the speed at which newer zoysiagrasses can initially spread by rhizomes and stolons when grown under shade. Further research should be conducted to determine if juvenile growth is an indicator of shade tolerance under natural tree shade or structures. Overall, results indicated that canopy heights cannot be used to directly predict shade tolerance but can be used to identify turfgrasses with reduced mowing frequency requirements. [ABSTRACT FROM AUTHOR]

The incorporation of dual‐purpose alfalfa (Medicago sativa L.) cultivars into bermudagrass (Cynodon spp.) is a viable option to extend the grazing season in Southern forage systems. However, data are limited on which harvest management strategy (HMS) optimizes the use of alfalfa‐bermudagrass (ABG) mixtures in the Southern US. A two‐year study evaluated ABG mixtures under three HMS [cut only (CO), graze only (GO), or cut and graze (CG)].in Headland, AL and Tifton, GA. Alfalfa‐bermudagrass mixtures utilized in this evaluation were ‘Bulldog 805’ alfalfa that was interseeded into ‘Tifton 85’ bermudagrass. Treatments were evaluated for forage, animal, and total system performance. Herbage accumulation varied by year and location (p < .01), but the number of harvests ultimately determined the total forage produced. Forage allowance was never limiting but did differ among treatments at Tifton, GA (p = .02). The CG HMS allowed for similar daily (p > .06) and liveweight gains (p > .56) on fewer days of grazing as compared to the GO treatments. The greater alfalfa percentage in the CG HMS translated to greater total digestible nutrients (TDN) and crude protein (CP), though not always statistically different. The CO HMS maximized system performance when evaluated for total gain (actual gains + predicted gains). However, the CG management allowed for more production opportunities across the season, thereby reducing economic risk. Future research should focus on evaluating the economic implications of introducing each HMS into ABG systems. [ABSTRACT FROM AUTHOR]

Bermudagrass (Cynodon dactylon (L.) Pers.) is one of the primary perennial forages in the southeastern USA. Newer hybrid cultivars have superior production and nutritive value compared to common ecotypes. However, there are many challenges facing bermudagrass production in the region. First, the bermudagrass stem maggot (BSM; Atherigona reversura Villeneuve) has severely damaged bermudagrass throughout the region. Strategically timed pyrethroid applications significantly reduce adult BSM populations, but efforts are needed to develop integrated pest management plans. Second, an increasing number of producers are noting challenges with green‐up following winter dormancy. This may be attributed to disease, unbalanced soil fertility, and weed pressure. Perhaps one of the most limiting factors for continued production is the deficit of sprigs and trained personnel to sprig hybrid bermudagrasses. This research is critically important as the need for cold‐tolerant bermudagrass is increasing as tall fescue (Lolium arundinaceum (Schreb.) S. J. Darbyshire) is declining due to changes in temperature and precipitation throughout the northern parts of the region. Plant breeders are investigating hybrid bermudagrass at latitudes >35° with respect to freeze or cold tolerance. Despite the many challenges facing hybrid bermudagrass in the southeastern USA, researchers are working to ensure its persistence, productivity, and availability for the future. [ABSTRACT FROM AUTHOR]

Inclusion of alfalfa (Medicago sativa) in bermudagrass (Cynodon dactylon) pastures improves nutritive value, increases grazing days, and reduces the need for synthetic nitrogen fertilizer. Crabgrass (Digitaria sanguinalis) is a very palatable warm-season annual grass with high nutritive value, prolific reseeding ability, and proclivity to volunteer in many southeastern pastures. Crabgrass is a common pest that requires pre-emergent herbicide technologies to control in alfalfa hayfields used to produce stored forage. However, in a grazing system, crabgrass could serve as a key component to a mixture aimed at increasing nutritive value and filling gaps in the grazing season. The purpose of this study is to evaluate the impact of alfalfa establishment timing (fall vs. spring) in bermudagrass pastures in the Coastal Plains, and the resultant impact of crabgrass inclusion rather than removal in alfalfa bermudagrass mixed pastures on nutritive value, botanical composition, forage accumulation, alfalfa stand density and persistence. This on-going two-year study is being conducted in Tifton, GA using a randomized complete block design with 4 replications of the following 6 treatments: Fall Alfalfa + Summer Crabgrass, Fall Alfalfa, Spring Alfalfa + Summer Crabgrass, Spring Alfalfa, Bermudagrass + Synthetic Nitrogen, and Untreated Bermudagrass Control. Data were collected from plots on a 28 to 35-day interval to determine botanical composition, forage availability, and nutritive value. The projected impact of this research is threefold; first, to identify how differing management strategies for restoring bermudagrass pastures are improved with inclusion of alfalfa. Second, it aims to quantify and support a recommended timing for planting alfalfa in the coastal plains, and third to estimate the impact of crabgrass inclusion in alfalfa bermudagrass systems. Data evaluation and statistical analysis is ongoing for this research and will be finalized in winter 2022. [ABSTRACT FROM AUTHOR]