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Fine fescues, a group of low-input turfgrasses, have exhibited weed suppression. Smooth crabgrass is a ubiquitous, warm-season, grassy weed that outcompetes many cool-season turfgrasses in summer (9). The presence of [...]

St. Augustinegrass [Stenotaphrum secundatum(Walter) Kuntze] is a commonly used warm‐season turfgrass for lawns in warm‐humid to tropical climates. Efforts to breed improved cultivars with enhanced abiotic and biotic stress tolerance are ongoing, but additional data on their growth and adaptation are needed. Twenty‐one commercially available St. Augustinegrass cultivars and eight experimental genotypes were planted in the field in Fayetteville, AR, in both 2009 and 2010 to study their stolon, leaf, and establishment characteristics, as well as winter survival. ‘Floratam’, ‘Floralawn’, ‘FX‐10’, ‘FA‐40’ (Mercedes™), ‘B12’ (Sapphire®), and WS had the highest stolon growth rate (>8.9 mm d−1), whereas ‘TR 6‐10’ (Amerishade®), ‘6‐72‐99’ (Delmar™), ‘6‐72‐182’ (Jade™), ‘6‐72‐130’ (Sunclipse™), 106G3, 106T3, and SV27 had the lowest stolon growth rate (<5.1 mm d−1). Cultivars ‘Floraverde’, Floralawn, Floratam, B12 (Sapphire), and ‘Texas Common’ were the quickest to establish. Principal component analysis (PCA) identified that cultivars with similar ploidy levels had similar growth characteristics as increasing ploidy resulted in wider and longer leaves, as well as larger stolon diameter and internode length. Cultivars considered dwarf types with short stolons or narrow‐short leaves grouped separately from cultivars with long stolons or wide‐long leaves. Genotypes VNS (Classic™), GF, VNS (Majestic™), ‘SS‐100’ (Palmetto®), ‘Raleigh’, TAES 5714, and Texas Common showed the highest winter survival and associated coverage after winter in both years. Results from this study are intended to help turfgrass breeders, turf producers, practitioners, and homeowners make informed cultivar selection decisions. Planting well‐adapted cultivars will reduce reestablishment costs from winter‐kill and ultimately increase sustainability.

Weed suppression has been observed in the fine fescues, a group of low‐input turfgrasses. Of the fine fescues, Chewings fescue (Festuca rubraL. ssp. commutataGaudin; CH) and strong creeping red fescue (F. rubraL. ssp. rubraGaudin; ST) displayed the strongest weed suppression ability in previous research while hard fescue (F. brevipilaTracey; HF) did not appear to have the same level of suppression. However, most of this research occurred more than 10 years ago and did not lead to improved cultivars. There is a need for confirmation of these results using diverse germplasm that may have genetic variability for weed suppression; this information would be useful for turfgrass breeding efforts. Our objective was to screen for weed suppression abilities in 19 fine fescue accessions originally collected in Europe, at two distinct field locations, St. Paul, MN and West Lafayette, IN, infested with smooth crabgrass (Digitaria ischaemum(Schreb.) Schreb. ex Muhl.). Our results confirmed previous reports that the F. rubrataxa are more crabgrass suppressive than HF. Chewings fescue and slender creeping red fescue [F. rubraL. ssp. littoralis(G. Mey.) Auquier; SL] displayed the strongest ability to suppress smooth crabgrass. Results also indicated that there is large variability between the entries within each taxon, including within HF. Slender creeping red fescues were relatively more weed suppressive than previously shown, and this taxon needs further attention. Results suggest further opportunities for plant breeders to develop new weed suppressive cultivars for low‐input turfgrass systems. Festuca rubrataxa are more crabgrass suppressive than F. ovina.There is large variability in weed suppression across entries within each fine fescue taxon.Opportunities exist for plant breeders to develop new weed suppressive cultivars.Future studies should aim to separate allelopathic effects from plant competition.

Turfgrass systems can be an important source or sink for greenhouse gases (GHG), including carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4). Further research is required in turfgrass systems; therefore, our objectives were to evaluate the effects of turfgrass species, growth rate, clipping management, and environmental conditions on GHG emissions. Greenhouse gas fluxes were measured in two separate field experiments in West Lafayette, IN. Experiment 1 investigated GHG flux in three cool‐season (C3) and two warm‐season (C4) turfgrass species during two growing seasons. Experiment 2 investigated fluxes in two C3cultivars with varying growth rates and under different clipping management regimes. The C3turfgrasses had the highest mean CO2flux rates ranging from 0.373 to 0.431 g CO2‐C m−2h−1compared with 0.273 to 0.361 g CO2‐C m−2h−1for C4turfgrasses. Mean hourly N2O flux rates ranged from 43.3 to 50.9 μg N2O‐N m−2h−1for C3compared with 11.1 to 14.4 μg N2O‐N m−2h−1for C4turfgrasses. Methane flux was more variable across time, but overall C4turfgrasses were more likely to be a CH4source, whereas C3turfgrasses were often a CH4sink. Growth rate and grass clipping management treatments had negligible impact on measured GHG flux. The differences in management practices specific to C3and C4turfgrasses had the largest impact on GHG flux. Results indicate the impact and importance of turfgrass species selection on GHG flux and also provide more information on our overall understanding on carbon and nitrogen cycling in urban soils. Turfgrass systems can be either a source or a sink for greenhouse gases.Further research is required on the effects of turfgrass species, growth rate, and clipping management.Higher CO2and N2O fluxes occurred in C3turfgrasses compared with C4turfgrasses.Management factors specific to C3or C4turfgrasses had the largest impact on GHG flux.Growth rate and grass clipping management had negligible impact on GHG flux.

Less than 3 yr post‐establishment, tall fescue accumulated more soil C (i.e., labile soil C, total soil C, and soil organic matter) than Kentucky bluegrass.Returning grass clippings for 2 yr increased both soil C (i.e., labile soil C and total soil C) and N (i.e., total soil N) compared to collecting clippings over the same period.Labile soil C increased linearly over the 5 yr of the experiment. Little information is available about how grass species and management practices, such as grass clippings management, influence soil C and N accumulation, especially labile soil C. Thus, the objective of this field experiment was to determine the labile soil C, total soil C, soil organic matter (SOM), and total soil N accumulation of Kentucky bluegrass (Poa pratensisL.) and tall fescue [Schedonorus arundinaceus(Schreb.) Dumort. syn. Festuca arundinaceaSchreb. syn. Lolium arundinaceum(Schreb.) Darbysh.] cultivars with differing growth rates under different grass clippings management practices. Differences in labile and total soil C occurred between turfgrass species after less than 3 yr of growth post planting: labile soil C was 9.9% higher (851 vs. 774 mg C kg−1soil), total soil C was 4.2% higher (24.8 vs. 23.8 g C kg−1soil), and SOM was 8.0% higher (41.7 vs. 38.6 g SOM kg−1soil) for tall fescue than Kentucky bluegrass. After 2 yr of clippings management treatments, plots where grass clippings were returned had 3.3% more labile soil C (826 vs. 800 mg C kg−1soil), 3.3% more total soil C (24.7 vs. 23.9 g C kg−1soil), and 4.6% more total soil N (2.28 vs. 2.18 g N kg−1soil) than those where clippings were collected. However, grass clippings management did not affect SOM. The results of this study highlight the importance of turfgrass selection and grass clippings management on soil C and N accumulation.

Methiozolin is a new herbicide reported to control annual bluegrass in creeping bentgrass putting greens. However, the appropriate application timing and rate to maximize efficacy is still not clear. The [...]

It is common for turf managers to overseed bermudagrass [Cynodonspp. (L.) Rich.] in autumn with cool‐season turfgrasses to enhance playing conditions and to provide a green playing surface with desirable color. The objectives of this study were to determine the effect of pre‐plant cultivation technique and post‐establishment traffic on the establishment of five overseeding species into a sward of bermudagrass. Plots were assigned one of three pre‐plant cultivation treatments of aerification, verticutting, or an untreated control. Five cool‐season turfgrasses including annual ryegrass (Lolium multiflorumL.), intermediate ryegrass (L. perenne× L. multiflorum), meadow fescue (Festuca pratensisHuds.), perennial ryegrass (L. perenneL.), and tetraploid perennial ryegrass (L. perenneL. 2n= 4x = 28) were overseeded 24 Sept. 2007, 17 Oct. 2008, and 28 Sept. 2009. Traffic was applied for three consecutive weeks beginning 1, 2, or 4 wk after planting or left untrafficked. Aerification and verticutting applied before seeding improved establishment compared to the untreated control. Perennial ryegrass was consistently among the species with the highest coverage across cultivation methods and traffic timings, while meadow fescue consistently had the poorest coverage across cultivation methods and traffic timings. Traffic initiated 4 wk after planting was more detrimental than traffic initiated 1 or 2 wk after planting. Based on these results, turfgrass managers would have best overseeding establishment by using aerification or verticutting as a pre‐plant cultivation technique and perennial ryegrass as a species.

Divots created by a golf stroke are a natural occurrence on golf courses and the resistance of turf to divot injury is an important factor that should be considered when selecting a turfgrass. Therefore, the primary objective of this experiment was to quantify the divot resistance for various bermudagrass (Cynodonspp. Rich.) and zoysiagrass (Zoysiaspp. Willd.) cultivars in a field experiment, with a secondary objective to compare evaluation methods for quantifying divot resistance. This study was conducted in Fayetteville, AR. Divot type, severity, and volume as well as a Turfgrass Shear Tester were used to determine divot resistance. ‘Riviera’ bermudagrass had the largest volume per divot (70 cm3), while the smallest divots (<28 cm3) were observed with ‘Cavalier’, ‘Diamond’, and ‘Zorro’ zoysiagrass. More force was required to displace divots from Diamond zoysiagrass than from Riviera, ‘Patriot’, or ‘Princess 77’ bermduagrass. Zoysia matrella(L.) Merr. consistently demonstrated greater divot resistance than Cynodon dactylon(L.) Pers. The four methods for evaluating divot resistance provided similar findings for divot resistance for the cultivars and species tested. These results provide researchers methods for evaluating divot resistance and will allow golf course superintendents to better select cultivars and species that will improve playing conditions and reduce divot injury.

Bermudagrass (Cynodonspp.) and zoysiagrass [Zoysiaspp. (Willd.)] are two of the most commonly used turfgrass species in the southern United States. Shade from trees is common on golf courses and limits turfgrass growth. Additionally, turfgrasses used on golf courses and sports fields are often subjected to traffic. The objective of this study was to evaluate shade and traffic effects on bermudagrass and zoysiagrass. Two shade treatments were imposed, full sun or 49% shade, using a light reducing fabric. A Cady Traffic Simulator was used to implement traffic stress. The cultivars with the highest coverage in shade without traffic were ‘Cavalier’, ‘Diamond’, ‘El Toro’, ‘Meyer’, ‘Palisades’, and ‘Zorro’ zoysiagrass, as well as ‘Princess 77’ and ‘Riviera’ bermudagrass. ‘Patriot’, ‘Tifsport’, and ‘Tifway’ bermudagrass and ‘Zenith’ zoysiagrass typically had the lowest coverage. Patriot bermudagrass and Zenith zoysiagrass consistently had the lowest coverage in shaded trafficked plots. El Toro, Palisades, and Zorro zoysiagrass as well as Princess 77, Riviera, Tifsport, and Tifway bermudagrass had the highest coverage (>72%) when trafficked under full sun for 4 wk. Coverage in shaded plots was decreased more from traffic than full‐sun plots. Riviera and Tifway bermudagrass had the most coverage after 6 wk of traffic in full sun. These studies identified cultivars of bermudagrass and zoysiagrass that perform better under reduced light and traffic stress.

Covers, mulches, and erosion-control blankets are often used to establish turf. There are reports of various effects of seed cover technology on the germination and establishment of warm-season grasses. The objective of this study was to determine how diverse cover technologies influence the establishment of bermudagrass (Cynodon dactylon), buffalograss (Buchloe dactyloides), centipedegrass ( Eremochloa ophiuroides), seashore paspalum (Paspalum vaginatum), and zoysiagrass (Zoysia japonica) from seed. Plots were seeded in June 2007 or July 2008 with the various turfgrass species and covered with cover technologies, including Curlex, Deluxe, and Futerra products, jute, Poly Jute, polypropylene, straw, straw blanket, Thermal blanket, and the control. Establishment was reduced in straw- and polyethylene-covered plots due to decreased photosythentically active radiation penetration or excessive temperature build-up, respectively. Overall, Deluxe and Futerra products, jute, and Poly Jute allowed for the highest establishment of these seeded warm-season grasses. [ABSTRACT FROM AUTHOR]