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Turfgrasses are essential landscape plants with social, environmental, and aesthetic services for urban ecosystems. However, more is needed to know how to establish them so that they can benefit from their ecosystem services in urban environments. This research examined some quality and morphological and physiological factors for the establishment and social and environmental service assessment of three warm-season turfgrasses, including Kikuyu grass (Pennisetum clandestinum), bermuda grass (Cynodon dactylon), and buffalo grass (Buchloe dactyloides), compared to the cool-season grass of tall fescue (Festuca arundinacea Schreb.). The experiment was split-plot in time, based on a randomized complete block design with eight replications. The main plot was the season with four levels, and the subplot was the four turfgrass species types. The results indicated that seasons and turfgrass types and their interaction significantly impacted most measured variables (p ≤ 0.01). Some quality measurements like turf density, color, texture, coverage, and quality after clipping and establishment confirmed the superiority of Buchloe dactyloides over the other species. Also, kikuyu grass showed higher turfgrass density, more potential for weed control, and higher coverage and growth rate but also showed invasiveness features. Tall fescue had the lowest visual aesthetic compared with the other turfgrass species. Warm-season turfgrasses adaptable to the ecology of the region should be used compared to tall fescue to achieve better turfgrass quality and social and ecosystem services for the sustainable development of arid urban environments. [ABSTRACT FROM AUTHOR]

Turfgrasses are essential landscape plants with social, environmental, and aesthetic services for urban ecosystems. However, more is needed to know how to establish them so that they can benefit from their ecosystem services in urban environments. This research examined some quality and morphological and physiological factors for the establishment and social and environmental service assessment of three warm-season turfgrasses, including Kikuyu grass (Pennisetum clandestinum), bermuda grass (Cynodon dactylon), and buffalo grass (Buchloe dactyloides), compared to the cool-season grass of tall fescue (Festuca arundinacea Schreb.). The experiment was split-plot in time, based on a randomized complete block design with eight replications. The main plot was the season with four levels, and the subplot was the four turfgrass species types. The results indicated that seasons and turfgrass types and their interaction significantly impacted most measured variables (p ≤ 0.01). Some quality measurements like turf density, color, texture, coverage, and quality after clipping and establishment confirmed the superiority of Buchloe dactyloides over the other species. Also, kikuyu grass showed higher turfgrass density, more potential for weed control, and higher coverage and growth rate but also showed invasiveness features. Tall fescue had the lowest visual aesthetic compared with the other turfgrass species. Warm-season turfgrasses adaptable to the ecology of the region should be used compared to tall fescue to achieve better turfgrass quality and social and ecosystem services for the sustainable development of arid urban environments.

Creeping bentgrass (Agrostis stolonifera) experiences quality decline during summer in the United States transition zone and warmer regions. Various bioproducts have been used to improve creeping bentgrass performance and to mitigate effects of summer stress in the United States transition zone. This 2-year study was carried out to examine if foliar application of seaweed extract (SWE; Ascophyllum nodosum)-based biostimulant Utilize VR could enhance creeping bentgrass nitrate reductase (NaR) activity, and root viability under heat and drought stress conditions. The Utilize® was sprayed biweekly on creeping bentgrass foliage at 0, 29, 58, 87, and 116 mL.m-2, with application volume of 815 L.ha-2. Two weeks after first application, plants were exposed to heat (35/25 °C, day/night) and drought stress (40% to 50% evapotranspiration replacement) conditions for 42 days in an environment-controlled growth chamber. In general, the abiotic stress caused turf quality reduction. Foliar application of UtilizeVR at 58, 87, and 116 mL.m-2 increased turf quality, leaf color ratings, leaf chlorophyll, carotenoid content, and net photosynthetic rate (Pn). UtilizeVR at 58, 87, and 116 mL.m-2 increased NaR activity by 26.5%, 16.3%, and 16.3%, respectively, when compared with the control. UtilizeVR at 58, 87, and 116 mL.m-2 increased root biomass, root length, surface area (SA), and root volume when compared with the control. UtilizeVR at 58 and 87 mL.m-2 improved root viability by 16.3% and 30.9%, respectively, when compared with the control. Our data indicate that the SWE-based biostimulant UtilizeVR improves nitrogen (N) metabolism and root viability. UtilizeVR treatment at 58 mL.m-2 biweekly can be considered an effective approach for improving creeping bentgrass performance during summer stress. [ABSTRACT FROM AUTHOR]

Abstract Background Incorporation of legume species into native North American pastures is considered an effective method to increase native pasture productivity and improve the nutritive value of forage. This study evaluated the effects of inclusion of purple prairie clover (PPC, Dalea purpurea Vent.), a native legume forage, with native cool-season grasses on the in vitro fermentation and in situ digestibility of mixed forages. Methods Whole plant PPC and mixtures of cool-season grasses were harvested when the PPC reached the vegetative (VEG), full flower (FL) and seedpod (SP) stages, and were combined in ratios (DM basis) of 0:100, 25:75, 50:50, 75:25 and 100:0 at each maturity. In vitro ruminal incubations using these mixtures were conducted for 48 h to determine gas production (GP), in vitro DM disappearance (IVDMD), total volatile fatty acids (VFA) and ammonia-N production. Mixtures of forages harvested when the PPC reached the FL stage and 50:50 mixture of forages harvested at VEG, FL and SP stages were incubated in the rumen of three heifers for 0, 2, 6, 12, 24, 48, 72 and 96 h to determine in situ degradabilities of DM, neutral detergent fibre (aNDF) and crude protein (CP). Results Contents of aNDF and ADF increased (P VEG > SP (P FL > SP (P

Tober Germplasm Virginia wildrye (Elymus virginicus L. [Poaceae]) is a selected class of natural germplasm released for conservation uses that include livestock forage, wildlife habitat, riparian plantings, and erosion control from wind and water. It fills the need for a selected, named release of Virginia wildrye for the indicated area of adaptation. It is a genetically diverse selection originating from 78 native seed collections from 37 counties in Minnesota and the Dakotas. Virginia wildrye provides added diversity, including shade tolerance and vigorous early establishment, to perennial herbaceous seed mixes. Its shorter life span fits in well with mixes that contain slowerestablishing warm-season species. An excellent seed producer that consistently produces seed when allowed to mature in its northern environment, Tober Germplasm Virginia wildrye is best adapted to the Northern Great Plains and Central Region of the US. Based on all field trial data, this release is expected to perform well wherever Virginia wildrye is recommended, particularly in North Dakota, South Dakota, and Minnesota. [ABSTRACT FROM AUTHOR]

Various climate adaptation strategies are being studied for the agricultural sector to address the effects of climate change. Global warming is predicted to have a significant influence on cool‐season grass production in Japan in terms of decreasing grass dry matter yield. The authors have studied adaptation strategies to maintain grass dry matter yield using orchardgrass, a cool‐season grass. However, it may be difficult to adapt to future climate conditions using management methods such as fertilizer application or changing grassland renovation cycles using only one grass species. In this study, a model was constructed formulating the relationship between temperature and yields of the main cool‐season grasses in Japan, and the effects of global warming on grass productivity were predicted. Two models were constructed, and the optimal one was selected using Akaike's information criterion. The selected model was then validated using correlations with observation data. We also compared areas suitable for cultivation at current and higher temperatures, which were produced as maps using the selected model. Bahiagrass, which is a warm‐season grass, was suitable for cultivation in coastal areas in southern Kanto under increased temperature condition. It may be useful, therefore, to convert to heat‐resistant grasses, such as orchardgrass or tall fescue, as temperatures rise. [ABSTRACT FROM AUTHOR]

Many cool-season grasses form permanent, mutualistic symbioses with asexual Epichloë endophytes. These fungal symbionts often perform a protective role within the association as many strains produce secondary metabolites that deter certain mammalian and invertebrate herbivores. Although initially a serious issue for agriculture, due to mammalian toxins that manifested in major animal health issues, selected strains that provide abiotic stress protection to plants with minimal ill effects to livestock are now commercialized and routinely used to enhance pasture performance in many farming systems. These fungal endophytes and their grass hosts have coevolved over millions of years, and it is now generally accepted that most taxonomic groupings of Epichloë are confined to forming compatible associations (i.e., symptomless associations) with related grass genera within a tribe. The most desired compounds associated with Epichloë festucae var. lolii, an endophyte species associated with perennial ryegrass, are peramine and epoxy-janthitrems. No other major secondary metabolites with invertebrate bioactivity have been identified within this association. However, other agriculturally beneficial compounds, such as lolines, have been discovered in related endophyte species that form associations with fescue grasses. A rationale therefore existed to develop novel grass-endophyte associations between loline-producing endophytes originally isolated from tall fescue with elite cultivars of perennial ryegrass to achieve a wider spectrum of insect bioactivity. A suitable loline-producing endophyte strain of Epichloë sp. FaTG-3 was selected and inoculated into perennial ryegrass. We hypothesed that endophyte transmission frequency, endophyte mycelial biomass and endophyte-derived alkaloid production would differ between the original tall fescue host and the artificial association. Consistent with our hypothesis, our data strongly suggest that plant species significantly affected the plant-endophyte association. This effect became more apparent for transmission frequency and endophyte biomass as the plants matured. Overall, the viable endophyte infection frequency was greater in the tall fescue host than in perennial ryegrass, at all sampling dates. Additionally, temperature was found to be a significant factor affecting endophyte transmission frequency, endophyte mycelial biomass and alkaloid production. Implications for the development of novel grass-endophyte associations are discussed.

The present study describes the spontaneous and experimental poisoning of goats by Festuca argentina in Argentine Patagonia. In April 2017, eight seven-month-old Creole male goats were accidentally introduced into a paddock that contained F. argentina. After four days, two of the goats were found dead and four out of the six remaining goats were clinically affected. Two of the latter had to be later euthanized in extremis. The main clinical signs were progressive nervous signs, starting with moderate muscle tremors, wide-based stance and ataxia. Postmortem examination was performed on the two euthanized goats. Epidermal fragments of F. argentina were found in the rumen samples from the necropsied goats and the fecal samples from the four affected goats. For the experimental poisoning, fresh sheaths of F. argentina collected from the paddock were offered to two goats at 10 g/kg body weight for 3 days. After 24–36 h, both animals exhibited severe muscle tremors, reluctance to move, tetanic convulsions, and opisthotonus. In both the spontaneously and experimentally poisoned goats, gross lesions were similar and consisted of dehydration, petechial hemorrhages in the epicardium and congestion. The main microscopic findings consisted of degeneration and loss of Purkinje cells and torpedoes in the granular layer of the cerebellum. The F. argentina sheaths collected from the pasture were found to contain tremorgenic indole-diterpene alkaloids. Taken together, the results of the present study suggest that the tremorgenic syndrome observed in the spontaneously poisoned goats was due to poisoning by F. argentina. • Festuca argentina causes spontaneous and experimental poisoning in goats. • Poisoning by Festuca argentina in goats is characterized by a tremorgenic syndrome. • Tremorgenic indole diterpenes are present in poisonous Festuca argentina. [ABSTRACT FROM AUTHOR]

Many cool-season grasses form permanent, mutualistic symbioses with asexual Epichloë endophytes. These fungal symbionts often perform a protective role within the association as many strains produce secondary metabolites that deter certain mammalian and invertebrate herbivores. Although initially a serious issue for agriculture, due to mammalian toxins that manifested in major animal health issues, selected strains that provide abiotic stress protection to plants with minimal ill effects to livestock are now commercialized and routinely used to enhance pasture performance in many farming systems. These fungal endophytes and their grass hosts have coevolved over millions of years, and it is now generally accepted that most taxonomic groupings of Epichloë are confined to forming compatible associations (i.e., symptomless associations) with related grass genera within a tribe. The most desired compounds associated with Epichloë festucae var. lolii , an endophyte species associated with perennial ryegrass, are peramine and epoxy-janthitrems. No other major secondary metabolites with invertebrate bioactivity have been identified within this association. However, other agriculturally beneficial compounds, such as lolines, have been discovered in related endophyte species that form associations with fescue grasses. A rationale therefore existed to develop novel grass-endophyte associations between loline-producing endophytes originally isolated from tall fescue with elite cultivars of perennial ryegrass to achieve a wider spectrum of insect bioactivity. A suitable loline-producing endophyte strain of Epichloë sp. FaTG-3 was selected and inoculated into perennial ryegrass. We hypothesed that endophyte transmission frequency, endophyte mycelial biomass and endophyte-derived alkaloid production would differ between the original tall fescue host and the artificial association. Consistent with our hypothesis, our data strongly suggest that plant species significantly affected the plant-endophyte association. This effect became more apparent for transmission frequency and endophyte biomass as the plants matured. Overall, the viable endophyte infection frequency was greater in the tall fescue host than in perennial ryegrass, at all sampling dates. Additionally, temperature was found to be a significant factor affecting endophyte transmission frequency, endophyte mycelial biomass and alkaloid production. Implications for the development of novel grass-endophyte associations are discussed. [ABSTRACT FROM AUTHOR]

Background: Incorporation of legume species into native North American pastures is considered an effective method to increase native pasture productivity and improve the nutritive value of forage. This study evaluated the effects of inclusion of purple prairie clover (PPC, Dalea purpurea Vent.), a native legume forage, with native cool-season grasses on the in vitro fermentation and in situ digestibility of mixed forages. Methods: Whole plant PPC and mixtures of cool-season grasses were harvested when the PPC reached the vegetative (VEG), full flower (FL) and seedpod (SP) stages, and were combined in ratios (DM basis) of 0:100, 25:75, 50:50, 75:25 and 100:0 at each maturity. In vitro ruminal incubations using these mixtures were conducted for 48 h to determine gas production (GP), in vitro DM disappearance (IVDMD), total volatile fatty acids (VFA) and ammonia-N production. Mixtures of forages harvested when the PPC reached the FL stage and 50:50 mixture of forages harvested at VEG, FL and SP stages were incubated in the rumen of three heifers for 0, 2, 6, 12, 24, 48, 72 and 96 h to determine in situ degradabilities of DM, neutral detergent fibre (aNDF) and crude protein (CP). Results: Contents of aNDF and ADF increased (P < 0.01), while CP decreased (P < 0.001) as PPC matured. Concentrations of extractable condensed tannins in PPC ranked as FL > VEG > SP (P < 0.05). Regardless of PPC proportions in the mixture, GP decreased (P < 0.05) with increasing PPC maturity. Increasing PPC proportions linearly increased (P < 0.001) GP, IVDMD and total VFA at VEG, but linearly decreased (P < 0.001) them at SP. Irrespective of PPC maturity, ammonia-N production linearly increased (P < 0.01) with increasing proportions of PPC and the concentration was higher (P < 0.05) at VEG than at FL and SP stages. Increasing proportion of PPC at either maturity linearly increased (P < 0.001) molar percentage of acetate (A) and branched-chain VFA, but linearly decreased (P < 0.001) molar percentage of propionate (P), resulting in a linearly increase (P < 0.001) in the A:P ratio. Increasing FL PPC in the mixture linearly and quadratically (P < 0.01) increased a (soluble fraction), but linearly and quadratically decreased (P < 0.01) b (potentially degradable fraction) for DM and aNDF, resulting in linear (P < 0.05) and quadratic (P < 0.01) increases in DM and aNDF maximum potential degradabilities (a + b). Effective degradabilities of DM and aNDF were also linearly and quadratically increased (P < 0.05), and CP was quadratically increased (P < 0.05) with increasing FL PPC, with the greatest effective degradability being observed with ratios between 50:50 and 75:25. Ruminal maximum potential degradabilities of DM and aNDF decreased (P < 0.001) as the forage matured. Effective degradability of DM ranked as VEG > FL > SP (P < 0.001), whereas the effective degradability of aNDF was similar between VEG and FL and both were greater (P < 0.01) than SP. Conclusions: Inclusion of vegetative PPC in a mixed forage diet resulted in the greatest digestibility and incorporation of PPC before seedpod stage with native grasses had a positive effect on ruminal fermentation. Effects of PPC on ruminal digestion depend on both the stage of maturity and its proportion in mixed legume-grass pastures. Pastures containing 50% of PPC in full flower stage would likely provide the greatest quality diet to grazing ruminants subject to potential animal selectivity. [ABSTRACT FROM AUTHOR]

Epichloë is a genus of filamentous fungal endophytes that has co-evolved with cool-season grasses with which they form long-term, symbiotic associations. The most agriculturally important associations for pasture persistence for grazing livestock are those between asexual vertically transmitted Epichloë strains and the pasture species, perennial ryegrass, and tall fescue. The fungus confers additional traits to their host grasses including invertebrate pest deterrence and drought tolerance. Selected strains of these mutualistic endophytes have been developed into highly efficacious biocontrol products and are widely utilized within the Americas, Australia, and New Zealand for pasture persistence. Less publicized is the antagonism Epichloë endophytes display towards multiple species of saprophytic and pathogenic microbes. This opinion piece will review the current literature on antimicrobial properties exhibited by this genus of endophyte and discuss the reasons why this trait has historically remained a research curiosity rather than a trait of commercial significance.

Aims: The Rio de la Plata grasslands are one of the largest areas of temperate humid and sub-humid grasslands of the world. A substantial fraction of these natural grasslands are preserved in Uruguay, occupying more than 60% of the country. So far, Uruguayan grasslands have been indirectly classified using only geomorphological and edaphic criteria. An adequate description of vegetation heterogeneity is a prerequisite to study ecosystem function and to design management and conservation strategies for this region. To this end, we present a classification of the natural grassland communities of Uruguay based on a wide and comprehensive set of phytosociological relevés. Study area: Uruguay. Methods: Three hundred eight grassland relevés were utilized for classification and ordination multivariate analyses. Agglomerative clustering based on the flexible Beta linkage method and Sørensen distance measure were employed to identify relevé groups. Indicator species analysis was also performed to identify diagnostic species. We used Non-metric multidimensional scaling to determine the main floristic gradients. Results: Five communities and 14 sub-communities were identified. Two of the communities were restricted to the "Basaltic" region of central and northern Uruguay, while the other three were distributed through the Eastern Hills, North Eastern Sedimentary Basin and the South Central regions. Three of the communities correspond to densely-vegetated grasslands associated with medium and deep soils. The remaining two communities correspond to sparsely-vegetated grasslands on shallow soils. The main floristic gradient separated sparsely-vegetated grasslands from densely-vegetated ones, and was related to soil and topographical characteristics. The second floristic gradient separated grasslands by their different geological substrates. Conclusions: In this study, we present the first attempt to conduct a vegetation classification of Uruguayan grasslands based on floristic composition. Vegetation typologies, like the one we propose, can be used as a framework to extrapolate point information on grassland management and vulnerability. [ABSTRACT FROM AUTHOR]

Grasslands enrolled in the Conservation Reserve Program (CRP) serve as one of the potential national herbaceous resources for use as a dedicated bioenergy feedstock. The goal of this project was to assess the yield potential and suitability of CRP grassland as a bioenergy feedstock source across the USA in regions with significant CRP land resources. In addition to that goal, one major objective of this project was to assess vegetation composition changes that also occurred on these different CRP grasslands over time with different harvest and fertilization management strategies. Three levels of nitrogen fertilization (0, 56, and 112 kg ha) and two harvest timings [peak standing crop (PSC) or end of growing season (EGS)] were evaluated for effects on biomass production and resulting species composition changes. Three sites in regions containing concentrated tracts of CRP grassland and representing variable climatic parameters were analyzed for vegetation composition trends over the course of six growing seasons (2008-2013). Specifically, a mixture of warm-season perennial grasses was evaluated in Kansas (KS), while a cool-season mixture was evaluated in Missouri (MO). North Dakota (ND) contained a mixture of both warm- and cool-season grasses. At the MO and KS sites, nitrogen fertilization significantly altered the grass and legume composition over time by lowering the legume percentage in the stand. In KS and ND, the two sites with warm-season grasses, harvesting in mid-summer at PSC, greatly reduced warm-season grass composition over time in favor of annual cool-season grass invaders or perennial cool-season grasses. Any shift to less desirable or less productive species limits the ability of these lands to provide a sustainable or reliable feedstock for bioenergy production. [ABSTRACT FROM AUTHOR]

The impact of horse preference and grass morphology on grazing muzzle effectiveness has not been investigated. The objective of this study was to determine the effectiveness of grazing muzzle use at reducing forage intake when horses grazed grasses with different morphology and preferences. The study was conducted in 2012 and 2013. Four horses were grazed in 2012, and three horses were grazed in 2013. Four species of perennial cool-season grasses were grazed in 2012 including Kentucky bluegrass (Poa pratensis L.), meadow fescue (Schedonorus pratensis Huds.), perennial ryegrass (Lolium perenne L.), and reed canarygrass (Phalaris arundinacea L.). In 2013, only Kentucky bluegrass and reed canarygrass were grazed because of winter kill of other species. Horses were allowed to graze a small pasture seeded with an individual species for 4 hours each day in June and August of 2012 and August and September of 2013. Horses grazed the same grass species for two consecutive days, one day with a muzzle and one day without. Before and after each grazing, a strip was mechanically harvested to determine initial and residual herbage mass. The difference was used to estimate forage intake. The effectiveness of a grazing muzzle was not affected by forage species (P ≥ .05). Use of a grazing muzzle decreased the amount of forage consumed by an average of 30% compared with not using a grazing muzzle (P < .0001). Results will aid horse owners and professionals in estimating forage intake of muzzled horses on pasture. [ABSTRACT FROM AUTHOR]

In northeast Mississippi, a native, cool-season grass component is needed for restoring and reclaiming grasslands and for providing quality forage for livestock. A field trial was established in Starkville, Mississippi, during fall 2010 to evaluate 18 entries of cool-season, perennial grasses (all Poaceae): 8 Elymus species including a Mississippi ecotype of southeastern wildrye (Elymus glabriflorus (Vasey ex L.H. Dewey) Scribn. & C.R. Ball), orchardgrass (Dactylis glomerata L), tall fescue (Schedonorus arundinaceus (Schreb.) Dumort., nom. cons.), timothy (Phleum pratense L), and wheatgrass (Thinopyrum intermedium (Host) Barkworth & D.R. Dewey) cultivars. The nonnative entries, specifically the orchardgrass and tall fescue cultivars, outperformed the native entries in height, dry matter yield, and ground cover ratings. Forage quality analysis, which included neutral detergent fiber, acid detergent fiber, and crude protein, however, indicated statistical similarities between Elymus species and domesticated, nonnative cultivars. Results from these experiments express the potential for improving agronomic characteristics in native germplasm for intensively managed grazing systems. [ABSTRACT FROM AUTHOR]

• Crabgrass and bermudagrass were lower in digestible energy, but higher in protein. • Crabgrass and bermudagrass were lower in non-structural carbohydrates. • Diurnal variation was more pronounced in cool-season grasses. Warm-season grasses have been suggested as alternative low non-structural carbohydrate (NSC) pasture forages. The purpose of this study was to evaluate nutrient composition and diurnal changes in soluble carbohydrates for the warm-season annual 'Quick-N-Big' crabgrass [CRB; Digitaria sanguinalis (L.) Scop.] and the warm-season perennial 'Wrangler' bermudagrass [BER; Cynodon dactylon (L.) Pers] in comparison to mixed cool-season grass [CSG; 'Inavale' orchardgrass (Dactylis glomerata [L.]), 'Tower' tall fescue (Lolium arundinaceum [Schreb.] Darbysh.), and 'Argyle' Kentucky bluegrass (Poa pratensis [L.])]. Samples were collected at 4-hour intervals over 3 d when each forage reached the boot stage of maturity. Digestible energy was greatest for CSG (2.29 ± 0.34 Mcal/kg) and lowest for BER (2.13 ± 0.34 Mcal/kg), while crude protein was lowest for CSG (16.1 ± 0.29%) and neutral detergent fiber was greatest for BER (60.0 ± 0.41; P ≤.0008). Non-structural carbohydrates were greater for CSG (17.6% ± 0.26%) compared to BER (10.6% ± 0.26%) or CRB (10.9% ± 0.26%; P <.0001). Overall, NSC was greatest in the afternoon and evening (14.5–14.9 ± 0.60%) and lowest in the early morning (11.2–11.4 ± 0.60%; P ≤.04), but diurnal variation was most pronounced in CSG versus either Warm-season grasses. Results of this study provide needed data on nutritional composition of CRB and BER and demonstrate that these grasses may serve as pasture forages for horses where NSC intake is of concern. Results also support recommendations for restricting grazing to early morning to limit NSC consumption, particularly in CSG pastures. [ABSTRACT FROM AUTHOR]

An assessment of genetic improvement in turf-type perennial ryegrass was performed at a network of six locations. A comparison was made of the turf performances of five natural populations, five forage-type cultivars used for turf seeding until the 1980s and 31 turf-type cultivars released from 1974 to 2004. Populations and cultivars were also compared in two spaced-plant experiments and in two seed-yield trials. Trait regressions on registration year of turf-type cultivars showed that breeding had been highly successful in improving the turf aesthetic merit (from +8·8 to +12·5% per decade according to seasons), wear tolerance (+5·4% per decade) and crown-rust resistance (+8·9% per decade) and in lessening the turf height increase rate (−0·43 mm day−1 per decade). Turf winter greenness had been marginally improved, whereas summer greenness and seed yield had not been significantly changed. A multivariate analysis provided evidence that turf density and fineness played a major role in the visual assessment of turf aesthetic merit and that wear tolerance was closely associated with turf density. Conflicting trait associations may have precluded improvements in turf ground-cover 3 months after sowing, turf winter greenness and turf persistency. [ABSTRACT FROM AUTHOR]

Prairies used for bioenergy production have potential to generate marketable products while enhancing environmental quality, but little is known about how prairie species composition and nutrient management affect the suitability of prairie biomass for bioenergy production. We determined how functional-group identity and nitrogen fertilization affected feedstock characteristics and estimated bioenergy yields of prairie plants, and compared those prairie characteristics to that of corn stover. We tested our objectives with a field experiment that was set up as a 5 × 2 incomplete factorial design with C3 grasses, C4 grasses, legumes, and multi-functional-group mixtures grown with and without nitrogen fertilizer; a fertilized corn treatment was also included. We determined cell wall, hemicellulose, cellulose, and ash concentrations; ethanol conversion ratios; gross caloric ratios; aboveground biomass production; ethanol yields; and energy yields for all treatments. Prairie functional-group identity affected the biomass feedstock characteristics, whereas nitrogen fertilization did not. Functional group and fertilization had a strong effect on aboveground biomass production, which was the major predictor of ethanol and energy yields. C4 grasses, especially when fertilized, had among the most favorable bioenergy characteristics with high estimated ethanol conversion ratios and nongrain biomass production, relatively high gross caloric ratios, and low ash concentrations. The bioenergy characteristics of corn stover, from an annual C4 grass, were similar to those of the biomass of perennial C4 grasses. Both functional-group composition and nitrogen fertility management were found to be important in optimizing bioenergy production from prairies. [ABSTRACT FROM AUTHOR]

Texas bluegrass ( Poa arachnifera Torr.) is a highly rhizomatous, dioecious, sexual, perennial, cool-season grass native to southern Kansas, Oklahoma, western Arkansas and most of Texas. This native species is of particular interest for development into an improved cool-season forage plant because of its heat tolerance and persistence under the extreme environmental conditions of the southern Great Plains. The objectives of this experiment were to determine water-soluble, non-structural carbohydrate and crude protein concentrations, forage dry matter yield, and in situ organic matter and crude protein disappearance from Texas bluegrass as affected by germplasm, maturity and time of harvest (morning and afternoon) at Woodward, Oklahoma. Crude protein concentrations ranged from 9 to 12% across seasons and did not differ between a morning and afternoon harvest. Dry matter yield ranged from 2130 to 5580 kg ha−1 over all harvest dates. Water-soluble, non-structural carbohydrate concentration was greater in the afternoon compared to morning harvests and ranged from 11 to 26%. Based on estimates from in situ digestion, the ratio of ruminally degradable crude protein to ruminally degraded organic matter in Texas bluegrass, it may compensate for the ruminally degraded nitrogen deficiency associated with dormant warm-season grasses during the winter. The forage nutritive value parameters estimated in this study indicate that Texas bluegrass has potential as an improved cool-season pasture grass. [ABSTRACT FROM AUTHOR]

Abstract: Prairies are a potential bioenergy feedstock that could benefit the environment while providing biomass for bioenergy. Increased diversity and nitrogen fertilization are two methods of increasing prairie productivity. Diversity may enhance complementarity of resource use within prairies, whereas the application of nitrogen fertilizer may cause priority effects whereby species with early phenologies or high responsiveness to fertilization are stimulated. We tested the effects of functional-group identity and nitrogen fertilization on resource capture and growth of prairie plants. To determine whether functionally-diverse mixtures of prairie plants exhibited complementarity and/or priority effects, we measured light interception, canopy duration, and aboveground biomass production of C3 grasses, C4 grasses, legumes, and multi-functional group mixtures grown without fertilization and with 150 kg ha−1 spring-applied nitrogen fertilizer. Under the conditions of our experiment, nitrogen consistently stimulated C3 grasses, whereas it stimulated C4 grasses only in the middle and late parts of the growing season and had no effect on legumes. In functionally-diverse mixtures, priority effects of C3 grasses in fertilized mixtures reduced overall resource capture and growth by suppressing growth of the more productive C4 grasses in the middle and late parts of the growing season. Complementarity occurred in unfertilized mixtures in which C3 and C4 grasses were dominant at different parts of the growing season. Prairies receiving more modest nutrient inputs than those used in this study or nutrient inputs later in the growing season may maximize the production of multiple ecosystem services by producing large amount of biomass while still capturing resources throughout the whole growing season. [Copyright &y& Elsevier]

Almost 30,000 ha (74,100 ac) of grassland were created in south-central Pennsylvania through the USDA Conservation Reserve Enhancement Program (CREP) from 2000 to 2004. To assess the use of these fields by grassland and other birds and to develop region-specific management guidelines, we conducted transect counts of singing birds in 103 CREP fields during 2002 to 2004 and measured within-field vegetation and landscape characteristics. Thirty-two bird species were found on fields during the breeding season. Red-winged blackbirds (Agelaius phoeniceus) were most numerous, followed by three shrub-scrub species. Grassland obligate species were rare and were most abundant on larger fields with a lower density of vegetation and a predominance of cool-season grasses. Abundances of shrub-scrub species were highest on smaller fields with a higher density of vegetation and a higher proportion of warm-season grasses. Avian use of CREP fields in Pennsylvania differs from Midwestern Conservation Reserve Program fields in a number of important ways. Shrub-scrub species were more common, which may be due to the small mean field size and the more forested landscape. In addition, grassland obligates were found in greater densities on fields of cool-season grasses than in fields of warm-season or mixed grasses. Targeted enrollment and management of large fields or those adjoining other grasslands for grassland birds and small fields or those adjoining woodlands for shrub-scrub species may be the best approach to maximize the benefits of CREP for a range of bird species. [ABSTRACT FROM AUTHOR]

There are potential agronomic and environmental benefits from incorporating warm-season (C4) grasses into temperate pasture systems, usually dominated by cool-season (C3) grasses, but there is a lack of information on how frequency and height of defoliation affects C4 grasses. Three greenhouse experiments were conducted under (i) spring, (ii) summer and (iii) spring + summer clipping regimes. In each experiment, the effects of clipping frequency (weekly and monthly) and clipping height (clipped to 5 and 10 cm) were determined on above- and below-ground net primary production (ANPP and BNPP) and total and seasonal dry matter (DM) yield for Andropogon gerardii Vitman (big bluestem, C4 grass) and Bromus inermis Leyss (smooth brome, C3 grass). Six replicates per treatment were used. In all experiments, ANPP and BNPP of smooth brome was greater than that of big bluestem although during late summer months big bluestem had higher DM yields of herbage than smooth brome. There were different effects of frequency and height of clipping for both species on two similar measurements: total annual DM yield and ANPP, indicating that the ability to generalize about the effects of defoliation from ecological and agronomic grassland standpoints is questionable. Clipping effects on ANPP and BNPP were different for summer-clipped pots than for spring, and spring + summer-clipped pots, indicating that management could be tailored to meet specific agronomic or conservation goals. [ABSTRACT FROM AUTHOR]

The animal waste treatment facility of Azabu University utilizes cultivation beds where liquid animal waste is purified by filtration through soil and vegetation. The beds are presently covered with zoysiagrass ( Zoysia japonica Steud.), which thrives in warm weather. However, the purification activities of this grass decrease during winter dormancy. To improve purification activity between autumn and early spring, we introduced redtop ( Agrostis alba L.), which thrives in cool conditions, into an experimental bed and compared the purification efficiency with that of zoysiagrass. Drainage purified through the bed of redtop showed significantly lower values of turbidity, chemical oxygen demand, total phosphorus and ammonium-nitrogen concentrations, and significantly higher nitrate-nitrogen concentrations than that through zoysiagrass during the late vegetative stage when redtop had the highest biomass. This suggested vigorous nitrification activity of rhizosphere under aerobic conditions afforded by redtop. The high purification efficiency of redtop appeared to be associated with better essential salts absorption and improved physicochemical properties of soil supporting its growth. The results showed that the purification efficiency of redtop is higher than that of zoysiagrass under seasonal low temperatures. [ABSTRACT FROM AUTHOR]

Crop composition at harvest affects the ensiling process and the resulting silage quality. The objectives of this study were to determine: (i) the effect of annual N-fertilizer application (0, 60, 120 and 180 kg N ha−1) and developmental stage (stem elongation, early heading, late heading and early flowering) on the ensiling properties and silage quality of the spring regrowth of timothy ( Phleum pratense L.) at two sites for 1 or 2 years, and (ii) the relationship between ensiling properties of the forage and the quality of the resulting silage. Laboratory silos with wilted forage at approximately 350 g dry matter (DM) kg−1 of fresh matter were prepared at each harvest and opened 150 d later for silage analysis. Higher rates of N-fertilizer application decreased the concentration of water-soluble carbohydrates (WSC), increased the buffering capacity (BC) and nitrate concentration, and decreased the ratio of WSC:BC, primarily in the early stages of development. The ensiling properties of timothy were, therefore, less favourable when high rates of N fertilizer were applied. Silage pH generally increased with increasing rates of N-fertilizer application; this increase was particularly evident at the first three developmental stages at one site in 1 year. Non-protein N (NPN) and soluble N concentrations of the silages increased with increased rates of N-fertilizer application at the first three developmental stages but decreased at early flowering. Ammonia-N concentration in the silages increased by 0·85, 0·56 and 0·67 when rates of N-fertilizer application were 60, 120 and 180 kg ha−1, respectively, compared with that when no N fertilizer was applied. Significant correlations between the composition of the forage ensiled and silage quality variables were found at sites in individual years but, when all data were combined, WSC concentration and BC, and their ratio in the forages, were not correlated with pH, and soluble-N and ammonia-N concentrations of the silages, and were weakly correlated with NPN and free amino acid-N concentrations of the silages. Silage quality was reduced by increased N-fertilizer application, primarily at the early developmental stages, and this can be attributed to a reduction in WSC concentration and an increase in BC of the forage. Water-soluble carbohydrate concentration, BC, and their ratio, however, were poor predictors of silage quality. [ABSTRACT FROM AUTHOR]

Epichloë is a genus of filamentous fungal endophytes that has co-evolved with cool-season grasses with which they form long-term, symbiotic associations. The most agriculturally important associations for pasture persistence for grazing livestock are those between asexual vertically transmitted Epichloë strains and the pasture species, perennial ryegrass, and tall fescue. The fungus confers additional traits to their host grasses including invertebrate pest deterrence and drought tolerance. Selected strains of these mutualistic endophytes have been developed into highly efficacious biocontrol products and are widely utilized within the Americas, Australia, and New Zealand for pasture persistence. Less publicized is the antagonism Epichloë endophytes display towards multiple species of saprophytic and pathogenic microbes. This opinion piece will review the current literature on antimicrobial properties exhibited by this genus of endophyte and discuss the reasons why this trait has historically remained a research curiosity rather than a trait of commercial significance. [ABSTRACT FROM AUTHOR]

Global biodiversity is threatened by invasive plant species. Without a thorough understanding of effective management strategies, minimizing their impacts while improving native species diversity will be challenging. Burning in fire-prone landscapes has been successful for managing invasive species and increasing native biodiversity, but it is unclear how specific fire regimes improve restoration practices in novel ecosystems where invasive plants have a similar growth phenology to native plants. We investigated fire as a restoration practice in the Northern Great Plains to decrease the cover of Kentucky bluegrass Poa pratensis (bluegrass), a perennial cool-season invasive grass phenologically similar to dominant native cool-season grasses, by 1) evaluating season of burn (early-growing season, late-growing season, and dormant season) in a field experiment to test differences in plant community composition and 2) manipulating fine fuels (3000-5000 kg ha -1 ) in an experimental approach to determine the effects of fire on plant survivability of selected native grasses and bluegrass. Bluegrass cover decreased 27% on all field burned plots the first year post-fire. Three years post-fire, late-growing season and dormant season treatments had 35% less bluegrass, whereas the early-growing season treatment was not significantly different from the control. Overall, fire altered the native plant community, with native plants more associated with burned plots. However, native plant community changes were only evident three years post-fire in late-growing season and dormant season burn treatments. In the experimental approach, native grasses and bluegrass experienced high rates of mortality (40-50%) at fuel loads above 4000 kg ha -1 and heat dosages above 30,000 °C·sec, features commonly associated with early-growing season burns. Therefore, early-growing season burns meant to reduce bluegrass may also impact native plants dominant in the region. Invasive species management is complicated in novel ecosystems when invasive plants have similar growth phenologies to native species. Control efforts should consider how different management strategies impact invasive and native plants alike. We found that late-growing season and dormant season burns, along with higher fuel loads, decreased bluegrass cover. Determining mechanisms of control in fire-prone landscapes is a crucial step to improving invasive plant control and increasing native biodiversity., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Forage grass production is an important component of profitable dairying along the Pacific Northwest coast. Neutral detergent fiber digestibility (NDFD) is increasingly being used in ration formulation and forage benchmarking. However, data on differences in NDFD between and within cool-season grass species is limited. Therefore, the objective of this study was to determine if NDFD differs between and within species. In experiment 1, 15 cool-season grass varieties were replicated 3 times each in 6 m2 randomized field plots. Included were 5 varieties each of perennial ryegrass (Lolium perenne), orchardgrass (Dactylis glomerata), and tall fescue (Lolium arundinaceum). In experiment 2, three diploid and three tetraploid cool-season ryegrass varieties (Lolium perenne) were replicated 3 times each in 6 m2 randomized field plots. Plots were mechanically harvested six times at approximately 28 d intervals beginning in March. Forty eight-hour in vitro neutral detergent fiber (NDF) digestibility was determined using 0.3 g of sample in F57 bags in a DaisyII Incubator (Ankom Technology, Fairport, NY). In experiment 1, yield (2124±79 kg DM/ha/cutting) was similar across species. Neutral detergent fiber was less for ryegrass compared to orchardgrass (47.1 vs 48.5±0.4%; P < 0.01), but similar to both of these grasses was tall fescue (48.0%). Neutral detergent fiber digestibility was greater for ryegrass compared to orchardgrass and tall fescue (80.4 vs 77.5±0.6% of NDF; P < 0.01). Digestible NDF did not differ and was 37.4±0.3% of DM or 799±32 kg/ha/cutting. Neutral detergent fiber increased (linear; P < 0.01) and NDFD decreased (quadratic, cubic; P < 0.05) as the growing season progressed. In experiment 2, yield (2220±110 kg DM/ha/cutting), NDF (47.2±0.5%), NDFD (80.7±0.5%), and digestible NDF (38±0.4% of DM and 851±47 kg DM/ha/cutting) were similar for diploid and tetraploid ryegrasses. These results indicate species, when managed intensively, has little effect on yield and digestibility. [ABSTRACT FROM AUTHOR]

Simulated rainfall and runoff were used to compare the effectivenessof 6 m and 3 m wide filter strips of switchgrass (Panicum virgatum) and cool- season filter strips consisting of bromegrass (Bromus inermis), timothy (Phleum pratense) and fescue (Festuca spp.) in reducing sediment, nitrogen and phosphorus in surface runoff from adjacent crop fields. The 6 m and 3 m wide strips represented 20:1 and 40:1 area ratios, respectively. Twelve plots, six each, in the switchgrass and cool- season grass strips, were laid out on Coland soil, having an average slope of 3%. Plots received simulated rainfall of 5.1 cm hr-1intensity and simulated runoff containing known quantities of sediment and nutrients. Three runon samples, each integrated over 15 minutes, and nine runoff samples, each integrated over five minutes, were collected from each plot and analyzed for sediment, total-N, NO-3-N, total-P and PO-4P.The 6 m wide filter strips removed 77% while the 3 m removed 66% of the incoming sediment from surface runoff. The 6 m filter strips removed 46% of total-N, 42% of NO-3-N, 52% of total-P, and 43% of PO-4-P; and the 3 m filter strips removed 28% of total-N, 25% of NO-3-N, 37% oftotal-P and 34% of PO-4-P. Differences between6 m and 3 m filter strips were significant (P < 0.05) for sediment and nutrient removal. Switchgrass filter strips removed significantly more total-N, NO-3-N, total-P and PO-4-P than cool-season grass filter strips (P < 0.05). [ABSTRACT FROM AUTHOR]