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Managing root zone moisture is critical to both the health and performance of sand‐based golf course putting greens. Ensuring adequate water for root uptake while preserving firm, dry surfaces is an ever‐present challenge. Time domain reflectometry (TDR) is an accepted technology for obtaining objective, nondestructive measurements of volumetric water content (VWC). However, portable TDR meters have limited ability to describe VWC near the surface, the region that ultimately defines putting green quality. The objective of this research was to expand the measurement capabilities of an existing TDR meter to estimate VWC in the uppermost 1.2 and 2.5 cm of sand‐based putting greens. Spacer‐blocks were constructed to effectively reduce the measurement depth of the Field Scout TDR300 (Spectrum Technologies Inc.). Samples from creeping bentgrass (Agrostis stolonifera L.) and ultradwarf bermudagrass [Cynodon dactylon (L.) Pers. × C. transvaalensis Burtt Davy] putting greens were removed, saturated, and dried for various intervals so that measurements with the modified TDR300 could be correlated to gravimetrically determined ground‐truth VWC. At both 1.2 and 2.5 cm, highly significant (p <.0001) quadratic prediction models were produced, with R2 values of 0.93 and 0.96, respectively. The use of spacer‐blocks expanded the capabilities of the TDR300, providing additional VWC data near the surface, thus creating a more comprehensive depiction of putting green moisture. The methods developed in this research have implications beyond turfgrass and may provide valuable information for studying seedling germination, disease development, or other situations where shallow, non‐destructive VWC measurements are beneficial. Core ideas: Measurement capabilities of portable time domain reflectometry (TDR) meters can be expanded by using spacer‐blocks.Modified TDR meters can estimate volumetric water content (VWC) at new, shallower depths of 1.2 and 2.5 cm.Quadratic prediction models provide good estimates of VWC across a range of conditions.Linear models tend to overestimate VWC at the lower end of observed values.Surface VWC measurements have potential use beyond golf course putting greens. [ABSTRACT FROM AUTHOR]

Homeowners with automated sprinkler systems water lawns frequently and may be unaware of the volume of water applied in their irrigation programs. Rain sensors (RS) and soil moisture sensors (SMS) may reduce watering by permitting scheduled irrigation to occur relative to recent rainfall or current soil moisture status and are available as add‐on technologies for residential sprinkler systems. As RS and SMS may positively impact irrigation scheduling, incorporating them into existing sprinkler systems may reduce water use and provide a return on investment (ROI), without compromising turfgrass quality. The objectives of this research were to determine the water savings of add‐on RS and SMS, estimate their ROI, and evaluate their impact on bermudagrass [Cynodon dactylon (L.) Pers.] lawn quality over three summers in Northwest Arkansas. An irrigation schedule without a sensor (control) was programmed to apply 0.5 inches of water twice a week for 17 wk. Water usage and turfgrass quality under the control were compared with two RS and two SMS, following the same program. During the 3‐yr study, RS and SMS reduced annual water use by an average of 22.1 and 66.2%, respectively. All treatments exhibited similar turfgrass quality and remained above the minimum level of acceptable quality. Under these experimental conditions, the average ROI for RS and SMS was estimated to be $87 and $200, respectively, within the first year of installation. Regional best management practices for watering bermudagrass lawns should include the incorporation of RS and SMS to reduce irrigation, maintain turfgrass quality, and save money. Core Ideas: Irrigation sensors may reduce water use without compromising turfgrass quality.When properly calibrated, soil moisture sensors can reduce water use by 66%.Rain sensors can reduce water use by 22% in a humid transition‐zone environment.Irrigation sensors may provide a return on investment of up to $200 within 1 yr. [ABSTRACT FROM AUTHOR]

Herbicide control options for bermudagrass [Cynodon dactylon (L.) Pers or C. dactylon x C. transvaalensis Burtt-Davy] include non-selective herbicides such as glyphosate (N-[phosphonomethyl] glycine), as well as selective graminicides such as fenoxaprop (Fenoxaprop-P-ethy) and fluazifop (Fluazifop-P-butyl). Regardless of the herbicide used, effective bermudagrass control can only be achieved with repeated applications. Fraise mowing has been recently introduced into the turfgrass industry and these machines can remove thatch and growing points down to a depth of 5.0 cm. Our hypothesis was that if a high percentage of the growing points of a bermudagrass stand were physically removed with fraise mowing, the remaining growing points would be more easily controlled with various herbicides. Six trials were conducted over two seasons to determine if fraise mowing and herbicides could be used in combination to improve bermudagrass control. Treatments included various combinations and timings of glyphosate (2.74 kg a.i. ha-1) and fluazifop (0.42 kg a.i. ha-1), applied to plots that were fraise mowed to a depth of 3.75 cm or not fraise mowed. Fraise mowing alone physically removed a significant amount of the bermudagrass growing points and provided partial bermudagrass control. A combination of fraise mowing and herbicide generally improved bermudagrass control over the herbicides alone. Herbicides applied after fraise mowing generally provided better bermudagrass control in comparison to applying herbicides prior to fraise mowing. Aggressive fraise mowing appears to be a tool that can improve bermudagrass control and could shorten the overall time window needed to remove existing bermudagrass from a site. [ABSTRACT FROM AUTHOR]

There is limited information regarding specific irrigation volumes required for establishing turfgrasses from seed, potentially leading many to overwater during establishment. The objectives of the following studies were to evaluate the impacts of irrigation volume and genetic drought resistance on the establishment of seeded tall fescue (Schedonorus arundinaceus Schreb.) and bermudagrass (Cynodon dactylon L.) cultivars in the transition zone. Two separate studies were conducted at the Milo J. Shult Agricultural Research and Extension Center in Fayetteville, AR. Tall fescue cultivars Penn RK4, a drought‐resistant cultivar, and Rebel Exeda were seeded and irrigated daily at 50, 75, 100, or 125% reference evapotranspiration (ETo) for 28 days in replicate trials. A second study evaluated seeded bermudagrass cultivars Princess 77, a drought‐resistant cultivar, and Sahara II, using the same irrigation regime for 28 days, in replicate trials. Daily irrigation replacing 50% ETo exhibited slower establishment compared to 100% ETo by an average of 11 and 2 days for tall fescue and bermudagrass, respectively. Irrigating at 75 and 100% ETo exhibited similar establishment for tall fescue and in 1 of 2 years for bermudagrass. In both studies, establishment rates did not differ when irrigating ≥100% ETo. Cultivars with known genetic drought resistance at maturity did not exhibit enhanced establishment rates under reduced irrigation regimes. These findings suggest daily irrigation replacing 100% ETo is favorable for establishing seeded cultivars of tall fescue and bermudagrass in the transition zone, and is a practical strategy for water‐conservation efforts. Core Ideas: Daily irrigation replacing 100% reference evapotranspiration should be used to establish turfgrass from seed.Using evapotranspiration‐based irrigation is a tool for conserving water during turf establishment.Genetic drought resistance among cultivars is not exhibited during establishment. [ABSTRACT FROM AUTHOR]

Determining daily light integral (DLI) requirements for turfgrass systems has been an effective method to quantify photosynthetically active radiation (PAR) necessary to maintain quality turfgrass in a research setting. However, there has been little research estimating DLI requirements of popular turfgrass cultivars of zoysiagrass [Zoysia matrella (L.) Merr. and Z. japonica Steud.], hybrid bermudagrass [Cynodon dactylon (L.) Pers. × C. transvaalensis Burtt Davy], and common bermudagrass [C. dactylon (L.) Pers.] used for teeing grounds and fairways on golf courses. The objective of this research was to (a) determine minimum DLI requirements of two zoysiagrasses, 'Cavalier' (Z. japonica) and 'Meyer' (Z. matrella), and two bermudagrasses, common bermudagrass (cultivar unknown) and 'Astro‐DLM' hybrid bermudagrass; and (b) investigate methodology in rapidly estimating DLI requirements in situ at area golf courses for the same cultivars. Cultivars were evaluated under 22, 40, 60, and 90% shade in a field research setting over two seasons from August through October 2016 and May through October 2017. Turfgrass quality continued to decline over the 2‐yr trial, emphasizing importance of multi‐year evaluations encompassing cumulative effects of shade on turfgrass. Estimated minimum DLI requirements for turf quality of Astro‐DLM hybrid bermudagrass, common bermudagrass, Cavalier zoysiagrass, and Meyer zoysiagrass were 20.4, 25.9, 15.0, and 21.1 mol m−2 d−1, respectively. In situ evaluations at golf course sites accurately estimated DLI requirements for three of four cultivars in comparison to those obtained in field research setting. Established minimum DLI requirements determined for cultivars in this study provide a baseline for site specific turfgrass selection. [ABSTRACT FROM AUTHOR]

Identifying and reporting color differences is important in turfgrass experimentation. Finding ways to improve color differentiation may be desirable. Research was conducted to determine if color‐distance modeling (∆E*ab) improves differentiation of color in images of hybrid bermudagrass [Cynodon dactylon (L.) Pers. × Cynodon transvaalensis Burtt‐Davy]. Colors differ perceptibly if ∆E*ab >1.0; magnitude of difference increases as ∆E*ab increases. Hue angle (θ) and dark green color index (DGCI) of untreated shoots; shoots treated with petroleum hydrocarbons; and turf treated with N, herbicides, or a growth regulator were determined by digital image analysis. Hue and DGCI means were separated using orthogonal contrasts; ∆E*ab was computed for each contrast. Delta E*ab was a good predictor of color difference magnitude. Association between p‐values for contrasts of θ or DGCI and ∆E*ab were strong; smaller p‐values corresponded to larger ∆E*ab. When log10p‐values for θ contrasts for 'Tifway' turf treated with N, herbicides, and a growth regulator were regressed on ∆E*ab, r2 =.9657 (y = − 0.602 − 0.9512x); for DGCI, r2 =.8743 (y = − 1.6097 − 0.8743x). Computing ∆E*ab helped avoid making false conclusions. Neither θ nor DGCI differed for Tifway treated with mesotrione or glyphosate (p =.2049,.6195) but ∆E*ab was 3.8 due to differences in saturation (p =.0137) and brightness (p =.0067). Computing ∆E*ab improved differentiation of turfgrass color by enhancing the accuracy of difference detection. Improving the ability to differentiate colors and avoidance of making false conclusions has advanced reporting of turfgrass color data. [ABSTRACT FROM AUTHOR]

Plant tissue desiccation and low-temperature exposure are two common causes of winter injury to ultradwarf bermudagrass [Cynodon dactylon (L.) Pers. × Cynodon transvaalensis Burtt Davy] putting greens. Unlike low-temperature exposure, winter damage caused by tissue desiccation can occur regardless of temperature and may beworsened by soil hydrophobicity. Wetting agents are commonly applied to actively growing ultradwarf bermudagrass putting greens to remedy the negative effects of soil hydrophobicity. Less is known about the effect of wetting agent applications to dormant ultradwarf bermudagrass putting greens. This research aimed to quantify the effects of a late-fall wetting agent application on winter injury and the soil volumetric water content of a sand-based ultradwarf bermudagrass putting green. Single applications of three wetting agents at two rates were made in early December of 2015, 2016, and 2017 to a 'TifEagle' ultradwarf bermudagrass putting green and were compared with an untreated control. Spring green-up and soil volumetric water content were monitored from March toMay of each season. Water drop penetration time tests were conducted twice each season to quantify reductions in hydrophobicity compared with the untreated control. On multiple dates, wetting agent treatments had significantly more green turfgrass coverage than the untreated control. In general, wetting agents reduced water drop penetration times in the top 2 cm of the soil profile. This research suggests that late-fall or winter applications of a wetting agent can reduce injury and enhance spring recovery of sand-based ultradwarf bermudagrass putting greens. [ABSTRACT FROM AUTHOR]

Shade from athletic stadium structures can be a significant deterrent to turfgrass performance. The objective of this study was to determine the daily light requirements of an overseeded or non‐overseeded bermudagrass (Cynodon spp.) turf maintained to simulate an athletic field. An experiment was established in 2013 on a mature bermudagrass [Cynodon dactylon (L.) Pers. cv. Riviera] turf that was either overseeded with perennial ryegrass (Lolium perenne L.) or non‐overseeded. Plots were re‐seeded with ryegrass each fall, but ryegrass was allowed to transition without chemical removal. Shade structures were installed to create four light level treatments including a full‐sun control (0% shade) and 30%, 60%, or 90% light‐reducing shade cloth. Quantum light sensors were mounted under each shade treatment and photosynthetic photon flux density (PPFD) was continuously measured and a daily light integral (DLI) calculated (mol PPFD m–2 d–1). The 2‐yr, average DLI values for shade treatments were 40.8 (0% shade), 26.2 (30% shade), 14.8 (60% shade) and 3.3 (90% shade) mol PPFD m–2 d–1. A range of growth and performance data were collected, including turfgrass coverage, clipping yields and leaf elongation rates. Overseeded and non‐overseeded bermudagrass failed to persist when 90% shade (DLI = 3.0 mol m–2 d–1) was imposed. Non‐overseeded bermudagrass required a higher DLI (26 mol m–2 d–1) to persist compared to overseeded bermudagrass (DLI = 21.8 mol m–2 d–1), primarily due to the enhanced shade tolerance of perennial ryegrass. However, the long‐term effects of shade began to decrease the quality of the overseeded turf by the end of the second year of the study. These data provide sports field managers with threshold light requirements for both overseeded and non‐overseeded bermudagrass turf. [ABSTRACT FROM AUTHOR]

Shade from athletic stadium structures can be a significant detriment to turfgrass performance. The objective of this study was to determine the effects of shade on rooting and playing surface stability, measured as traction, on overseeded or non‐overseeded bermudagrass (Cynodon spp.) turf. An experiment was established in 2013 on a mature bermudagrass [Cynodon dactylon (L.) Pers. cv. Riviera] turf that was either overseeded with perennial ryegrass (Lolium perenne L.) or non‐overseeded. Shade structures were installed to create four light level treatments, including 0%, 30%, 60%, or 90% light‐reducing shade cloth. The light treatments resulted in average daily light integrals (DLI) of 40.8, 26.2, 14.8, and 3.3 mol m–2 d–1, respectively. Data were collected on rooting characteristics, species composition, and two forms of traction measurements. Moderate levels of shading (30%) caused a significant decline in rooting characteristics in non‐overseeded turf, while rooting of overseeded turf was not significantly affected until a 60% light reduction. Rotational resistance and peak horizontal force, measurements of athlete traction, were affected by increasing shade in both overseeded and non‐overseeded turf, but the association between traction and a minimum DLI was not conclusive. The persistence of bermudagrass in overseeded turf was significantly reduced at all shade levels studied. This study clearly demonstrates that rooting, bermudagrass persistence and traction of overseeded and non‐overseeded bermudagrass athletic fields are negatively affected by even modest levels of shade. [ABSTRACT FROM AUTHOR]

Bermudagrass (Cynodon spp.) is a warm season turfgrass that spreads by stolons and rhizomes. The present study aimed to increase knowledge on development of stolons and rhizomes in fertile ('LaPaloma' and 'Yukon') and sterile ('Patriot' and 'Tifway') cultivars of bermudagrass. A plot trial was established in May 2013 in Legnaro, northeastern Italy. Fertile cultivars were seeded while sterile cultivars were established by vegetative plugs. Turf samples were collected from autumn 2013 until summer 2015 on March, July, and October. Total length of stolons and rhizomes was measured and total dry weight was determined. The concentration of starch in stolons and rhizomes in October was also determined. The stolon and rhizome density per unit area, the rhizome specific weight, and the rhizome/stolon length and weight ratios were calculated. Sterile cultivars had higher stolon and rhizome density compared to fertile cultivars for both length. In all cultivars, the production of stolons was favoured over that of rhizomes and rhizomes began to develop more in the second season after establishment. Cultivars did not differ significantly in starch content, indicating no relationship between stolon and rhizome density and carbohydrate reserve accumulations. Abbreviations: LD: length density per unit area; WD: weight density per unit area; SW: specific weight; LR: rhizome-to-stolon length ratio; WR: rhizome-to-stolon weight ratio; TS: total starch per unit area [ABSTRACT FROM AUTHOR]

Early-spring flowering bulbs can increase biodiversity while adding color to lawns and other grassy areas. However, few studies have investigated whether bulbs can flower and persist in warm-season lawns or provide feeding habitat for pollinating insects. Thirty early-spring flowering bulbs, including species of Anemone, Chionodoxa, Crocus, Eranthis, Hyacinthus, Ipheion, Iris, Leucojum, Muscari, and Narcissus, were established in bermudagrass (Cynodon dactylon L. Pers) and buffalograss [Buchloe dactyloides (Nutt.) J.T. Columbus] lawns in late autumn 2015 in Fayetteville AR. Bulbs were assessed over three growing seasons for flowering characteristics, persistence, and their ability to attract pollinating insects. A growing degree day model was also developed to predict peak flowering times in our region. Numerous bulb entries produced abundant flowers in bermudagrass and buffalograss lawns in the first year after planting, but persistence and flower production were reduced in both the second and third years of the trial. Five bulbs persisted for multiple years in both turfgrass species and continued to produce flowers, including Crocus flavus Weston 'Golden Yellow' (crocus), Leucojum aestivum L. (spring snowflake), Narcissus (daffodil) 'Baby Moon', Narcissus 'Rip Van Winkle', and Narcissus 'Tete-a-Tete'. Several bulbs, primarily crocuses and Muscari spp. (grape hyacinth), were also observed to attract pollinating insects, principally honey bees (Apis mellifera). These results demonstrate that some early-spring bulbs can persist in competitive warm-season turfgrasses, while providing pollinator forage, but species and cultivar selection is critical for long-term success. [ABSTRACT FROM AUTHOR]

Climatic changes and the need to reduce water consumption for irrigation have led to expanded use of warm-season turf species in transitional zones. Turf managers are often hesitant to use warm-season species because they undergo dormancy for a long period during the winter. Although this issue might be addressed by mixing cool- with warm-season species, there is a lack of information on the performance and dynamics of species succession in such turfgrass mixtures. A 2-yr investigation was conducted in Legnaro, Italy, and Fayetteville, AR, to test the turf quality and species succession in mixtures of various cultivars of bermudagrass (BG) [Cynodon dactylon (L.) Pers.] with Kentucky bluegrass (KBG) (Poa pratensis L.). Bermudagrass cultivars, Yukon and Veracruz, were seeded in June 2011 at 5 g m-2 and KBG cultivars Brooklawn, Mystere, and Nublue Plus were overseeded in September 2011 at 30 g m-2. Across both studies, the frequency of BG in the mixture was generally higher for Yukon and ranged from 40 to 95%. However, the mixtures with Veracruz had superior turf quality in Legnaro from October 2012 to March 2013. The species succession was influenced by BG cultivars, whereas KBG cultivar had little effect on the rate of plant composition change. On the basis of these results, the choice of BG cultivar appears critical for establishing functional KBG and BG mixtures in transitional zones. [ABSTRACT FROM AUTHOR]

In the transition zone, a primary concern in managing warm-season turfgrasses is turf survival under low temperatures. The objectives of this study were to determine the effects of three N fertilization schedules on stolon carbohydrates and crude protein (CP) reserves of four bermudagrasses [Cynodon dactylon (L.) Pers.] and a seashore paspalum (Paspalum vaginatum Sw.). A field trial was performed at the agricultural experimental farm of Padova University (northeastern Italy). Bermudagrass cultivars Princess-77, Riviera, SWI 1014, and Yukon and seashore paspalum 'Sea Spray' were compared under three N fertilization schedules: (i) 6.7 g N m-2 on 15 May, 15 June, and 15 August, (ii) 5 g N m-2 on 15 May, 15 June, 15 August, and 15 October, and (iii) 4 g N m-2 on 15 May, 15 June, 15 August, 15 September, and 15 October. Turf samples measuring 20 by 20 by 4 (depth) cm were collected monthly from September to April 2009 to 2010 and 2010 to 2011. The stolons were separated from the remainder of the samples and starch, water-soluble carbohydrates (WSC), and CP were determined on a dry matter basis. The bermudagrass cultivar Riviera was characterized by high stolon density and showed highest carbohydrates (starch and WSC) content along with Yukon. Late-season applications of N had limited influence on carbohydrates content but increased the concentrations of CP from November through April. [ABSTRACT FROM AUTHOR]

A primary concern in managing warm-season turfgrasses within the transition zone is the lengthy dormant period, during which these swards lack green color. The objectives of this study were to determine the effects of three N fertilization schedules on spring green-up and fall color retention of bermudagrass [Cynodon dactylon (L.) Pers.] and seashore paspalum (Paspalum vaginatum Sw.). A field trial was performed at the agricultural experimental farm of Padova University (northeastern Italy). Bermudagrass cultivars Princess-77, Riviera, SWI 1014, and Yukon and seashore paspalum 'Sea Spray' were compared under three N fertilization schedules: (i) 6.7 g N m-2 on 15 May, 15 June, and 15 August, (ii) 5 g N m-2 on 15 May, 15 June, 15 August, and 15 October, and (iii) 4 g N m-2 on 15 May, 15 June, 15 August, 15 September, and 15 October. Spring green-up was estimated weekly as a percent green turfgrass coverage from 15 March to 15 June of 2010 and 2011. Fall color retention was visually rated from September to November of 2010 and 2011. Sea Spray seashore paspalum had later spring green-up and better fall color than the bermudagrass cultivars, which differed widely in terms of spring green-up and fall color retention. Fall-applied N enhanced green-up of all the grasses tested and extended fall color retention of bermudagrass cultivars. This study revealed that protracting applications of N fertilizer until late season may improve quality performance of warm-season grasses without increasing annual N applied. [ABSTRACT FROM AUTHOR]

It is common for turf managers to overseed bermudagrass [Cynodon spp. (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 multijlorum L.), intermediate ryegrass (L. perenne × L. multijlorum), meadow fescue (Festuca pratensis Huds.), perennial ryegrass (L. perenne L.), and tetraploid perennial ryegrass (L.perenne L. 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 afi:er 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. [ABSTRACT FROM AUTHOR]

Data are lacking in the quantification of N loss mechanisms associated with foliar fertilizer applications that are common to golf course and putting green turfgrass management. This study was conducted to measure ammonia (NH3) volatilization after application of foliar N (as urea) to creeping bentgrass [Agrostis stolonifera L. var. palustris (Huds.) Farw. cv. Penn Al] and hybrid bermudagrass [Cynodon dactylon (L.) Pers. × C. transvaalensis Burtt Davy cv. Tifeagle] putting greens in Fayetteville, AR. Urea was spray-applied monthly, May through September, at rates of 0.5 and 1.25 g N m-2. Ammonia (NH3) volatilization, over a 24 h period, was measured via boric acid trapping within closed, static diffusion chambers. Month of year and N rate significantly affected the amount of N volatilized from the turfgrass canopy. Measured NH3 volatilization was consistently low each year for both species, with average annual NH3 volatilization of 0.35% and 2.55% from creeping bentgrass and hybrid bermudagrass, respectively. A trapping efficiency study was conducted and revealed that 35 to 50% of evolved NH3-N was directly absorbed by plant tissue enclosed within the chambers. While it was determined that the NH3 trapping methodology used here could not account for all of the NH3 volatilized, data from this study does support the conclusion that foliar N (as urea) applications to putting green turf can be made to actively growing plant tissue throughout the season without concern for substantial N loss via NH3 volatilization. [ABSTRACT FROM AUTHOR]

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 (Cynodon spp. Rich.) and zoysiagrass (Zoysia spp. 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 wore 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. [ABSTRACT FROM AUTHOR]

Foliar fertilization often comprises a significant portion of the total annual N applied to putting greens. This study was initiated to evaluate the efficiency of this practice under field conditions. 15N-labeled urea was used to quantify seasonal uptake of foliar-applied N by creeping bentgrass (Agrostis stolonifera var. L. palustris (Huds.) Farw. 'Penn Al') and hybrid bermudagrass (Cynodon dactylon (L.) Pers. x C. transvaalensis Burtt Davy 'Tifeagle') managed as putting greens. Urea was spray-applied monthly, May through September, at rates of 0.5 and 1.25 g N m-2. Both species absorbed urea rapidly, with 24 to 67% of the fertilizer N entering the foliage within 1 h following treatment; peak foliar absorption was generally observed at 4 h after treatment. Percentage of foliar uptake was significantly reduced at higher application rates for both species. In addition, absorption of urea-N by foliage of both species was affected by month of application and year. When averaged across all sampling times and N rates, foliar absorption percentages were similar between the two species, ranging from 36 to 69% for creeping bentgrass and 38 to 62% for bermudagrass. Overall, foliar absorption efficiency was variable and there were no consistent seasonal trends associated with these differences. [ABSTRACT FROM AUTHOR]

Bermudagrass (Cynodon spp.) and zoysiagrass [Zoysia spp. (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. [ABSTRACT FROM AUTHOR]

Lie is the position in which a golf ball comes to rest following a stroke. Although the lie of a golf ball is an important factor affecting the play of the next stroke, there have been few attempts to measure this characteristic or determine how management practices, turfgrass species, or cultivars affect ball lie. The objective of this study was to develop and demonstrate a new technique using digital image analysis for measuring ball lie in various turfgrasses. The technique uses a stage that positions a digital camera at the top of a mowed turfgrass canopy and collects an image of a golf ball positioned at the same focal length in each frame. The image was then subjected to digital image analysis to determine the percentage of the golf ball that was visible above the canopy. The new technique was calibrated by positioning a golf ball at a defined height above the soil and also compared with another published technique, called Lie-N-Eye, for accuracy and ease of use. The image analysis technique could distinguish changes in ball height within a turfgrass canopy. In addition, collecting data with the technique was easier and faster compared with the Lie-N-Eye, the only other method of ball lie analysis available. However, the two devices produced data that were highly correlated. Two cultivar trials of bermudagrass (Cynodon spp.) and zoysiagrass (Zoysia spp.) were evaluated using the technique, and significant differences among cultivars in both species were demonstrated. [ABSTRACT FROM AUTHOR]

Most pollinating insects require a season-long succession of floral resources to fulfill life-cycle requirements. Incorporating forbs into turfgrass sites may create a season-long sequence of flowers to support foraging pollinators. However, persistence of forbs in warm-season turfgrasses such as bermudagrass (Cynodon spp.) may be affected by the competitive nature of the turfgrass and routine management practices such as mowing. A 2-year study was conducted to evaluate seven forbs (Bellis perennis L., Lotus corniculatus L., Prunella vulgaris L., Trifolium fragiferum L. 'Fresa', Trifolium repens L. 'Durana' and 'Resolute', Trifolium subterraneum L.) for persistence and ability to produce floral resources for pollinating insects in a low maintenance bermudagrass lawn. Plugs of each species were incorporated into 'Riviera' bermudagrass in Apr. 2016. Vegetative cover, flower production, flowering period and pollinator foraging were assessed. Prunella vulgaris bloomed July through August and achieved 100% cover (0% bermudagrass) by 2017. Trifolium repens achieved a more balanced competitive density with the bermudagrass and produced flowers from June through August in both years. Trifolium fragiferum persisted over two growing seasons but only bloomed in 2017. Bellis perennis, Lotus corniculatus and Trifolium subterraneum did not persist. Pollinators were observed foraging on all persistent, flowering forbs, including Trifolium repens, Prunella vulgaris, and Trifolium fragiferum. Trifolium repens and Prunella vulgaris produced the most flowers and attracted the most pollinators. [ABSTRACT FROM AUTHOR]

Traffic resistance of turfgrasses is an essential indicator of urban recreational and sports turf quality (TQ). In our study, four turfgrass species were investigated for their wear resistance. A self-made traffic simulator was used to determine the wear resistance of the study turf area in a 2-year field trial (2019–20). The experimental plots were established using a randomized block design with three replicates. The morphological characteristics, soil physical properties, and physiological indices of the grasses were analyzed. Using the acquired quantitative data, we set the turf cover index (TCI), the turf quality index (TQI), and the shoot density index (SDI) as the wear tolerance index, and assessed the correlations among these morphological characteristics, soil physical properties, physiological indices, and wear tolerance. ‘Lanyin III’ zoysiagrass and ‘Tifgreen’ hybrid bermudagrass provided relatively greater wear tolerance, followed by ‘Qingdao’ zoysiagrass and common bermudagrass after 12 weeks of traffic exposure in 2019 and 2020. Traffic changes the soil physical properties and affects the physiological metabolism of turfgrasses. Leaf morphology characteristics and the mechanical strength of these grasses were related significantly to TCI, TQI, and SDI, and most physiological responses and soil properties correlated significantly with TCI and TQI. Our findings of the correlations among physiological responses, soil properties, leaf morphology, and wear tolerance will allow grass breeders to evaluate their breeding procedures more efficiently. [ABSTRACT FROM AUTHOR]