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Residential lawns are highly managed ecosystems that occur in urbanized landscapes across the United States. Because they are ubiquitous, lawns are good systems in which to study the potential homogenizing effects of urban land use and management together with the continental-scale effects of climate on ecosystem structure and functioning. We hypothesized that similar homeowner preferences and management in residential areas across the United States would lead to low plant species diversity in lawns and relatively homogeneous vegetation across broad geographical regions. We also hypothesized that lawn plant species richness would increase with regional temperature and precipitation due to the presence of spontaneous, weedy vegetation, but would decrease with household income and fertilizer use. To test these predictions, we compared plant species composition and richness in residential lawns in seven U.S. metropolitan regions. We also compared species composition in lawns with understory vegetation in minimally-managed reference areas in each city. As expected, the composition of cultivated turfgrasses was more similar among lawns than among reference areas, but this pattern also held among spontaneous species. Plant species richness and diversity varied more among lawns than among reference areas, and more diverse lawns occurred in metropolitan areas with higher precipitation. Native forb diversity increased with precipitation and decreased with income, driving overall lawn diversity trends with these predictors as well. Our results showed that both management and regional climate shaped lawn species composition, but the overall homogeneity of species regardless of regional context strongly suggested that management was a more important driver. [ABSTRACT FROM AUTHOR]

• Residential lawns have higher predatory activity as compared to the sod farms. • Predation on Spodoptera frugiperda larvae was higher in residential lawns than sod farms. • Clay models resembling S. frugiperda larvae captured diverse impression types. • Camera recording showed ants as active predators in both turfgrass systems. The occurrence and abundance of predatory fauna in turfgrass systems have been reported; however, the activity of predators has rarely been described. The fall armyworm Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae) is a major pest of turfgrass in the United States for which arthropod predation is not considered a key pest management option, but the role of predation on S. frugiperda has not been assessed in turfgrass systems, which are managed at varying intensities. Thus, the objective of this study was to determine (1) the incidence and (2) the severity of predation in less intensively managed residential lawns and intensively managed sod farms. The percentage of predation on live S. frugiperda sentinel larvae and the percentage of predation and its severity on clay models were significantly greater in the residential lawns than in the sod farms. Among the seven impression types recorded on clay models, paired marks were the most abundant. Four new impression types, deep cut marks, stacked surface marks, scooped marks, and U-shaped marks, were observed on clay models in both turfgrass systems. Formicids were documented at significantly greater densities than were other predatory groups, such as carabids. Thus, the results show the need for enhanced predatory activity in sod farms by developing integrated pest management strategies and adopting measures to conserve natural enemies. [ABSTRACT FROM AUTHOR]

Highlights: [•] We spatially project water usage under two strategies of (sub)urban growth. [•] We examine the relationship between water use and land cover using household-scale data. [•] We find that lawn area is a significant predictor of annual water use. [•] We project that under the Smart Growth scenario a 5% reduction in additional water use can be achieved. [•] We find that urban design may be an alternative solution for towns seeking to reduce water use. [Copyright &y& Elsevier]

Abstract: Turfgrass irrigation policies have been implemented in various regions of the U.S. to reduce domestic water consumption. Mandatory restrictions are often enforced by issuing citations to violators with the intent to promote compliance and deter violations. This study provides a detailed investigation of past water restrictions and compliance, and attempts to determine which factors are related to high rates of water usage within communities of Tampa, FL. The adjusted rainfall rate had the most significant relationship with water usage in the communities under study. Water usage increased in each examined community after it transitioned to more stringent water usage restrictions, with cited restriction violators increasing usage to a greater extent than their uncited counterparts. This increase may primarily be attributed to conflicts between the local water consumption policy and binding homeowner association rules. When the once-a-week usage restriction was in place, the area faced drought conditions. Therefore, homeowners irrigated more to meet the water needs of their lawns despite the restrictions imposed on them by their local government. [Copyright &y& Elsevier]

Soil analyses were conducted on home lawns across diverse ecoregions of the U.S. to determine the soil organic carbon (SOC) sink capacity of turfgrass soils. Establishment of lawns sequestered SOC over time. Due to variations in ecoregions, sequestration rates varied among sites from 0.9 Mg carbon (C) ha year to 5.4 Mg C ha year. Potential SOC sink capacity also varied among sites ranging from 20.8 ± 1.0-96.3 ± 6.0 Mg C ha. Average sequestration rate and sink capacity for all sites sampled were 2.8 ± 0.3 Mg C ha year and 45.8 ± 3.5 Mg C ha, respectively. Additionally, the hidden carbon costs (HCC) due to lawn mowing (189.7 kg Ce (carbon equivalent) ha year) and fertilizer use (63.6 kg Ce ha year) for all sites totaled 254.3 kg Ce ha year. Considering home lawn SOC sink capacity and HCC, mean home lawn sequestration was completely negated 184 years post establishment. The potential SOC sink capacity of home lawns in the U.S. was estimated at 496.3 Tg C, with HCC of between 2,504.1 Gg Ce year under low management regimes and 7551.4 Gg Ce year under high management. This leads to a carbon-positive system for between 66 and 199 years in U.S. home lawns. More efficient and reduction of C-intensive maintenance practices could increase the overall sequestration longevity of home lawns and improve their climate change mitigation potential. [ABSTRACT FROM AUTHOR]

This research was conducted to facilitate utilization of the widely accepted United States Golf Association (USGA) recommendations for physical properties of root zone mixtures when designing a putting green using geotextile atop Airfield Systems' AirDrain in place of the standard gravel drainage layer. Water storages in greens that utilized geotextile atop AirDrain as the drainage structure were compared with water storage in standard USGA-design greens constructed with gravel drainage. Three root zone mixture treatments were combined with four geotextile-atop-AirDrain drainage treatments and three gravel drainage treatments to cover a range of possible combinations of materials for construction of a putting green. Each root zone drainage treatment was replicated three times in small test greens. After irrigation that produced drainage, water tensions at the bottom of the root zones of greens constructed with geotextile atop AirDrain were, on average, 56 mm water less than those in test greens constructed with gravel. As a consequence of the differences in tensions, about 12 mm (~1/2 inch) more water was stored in root zones of test greens constructed with geotextile atop AirD-rain compared to those constructed with gravel. If the USGA recommendations for a root zone mixture were to be used for an Airfield System's designed putting green, it would appear that the tension at which the air-filled porosity and capillary porosity were determined should be lowered by approximately 50 mm water. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) sequestration and the impact of carbon (C) cycling in urban soils are themes of increasing interest. A model was developed to investigate the potential of C sequestration in home lawns. The model contrasted gross C sequestered versus the hidden C costs (HCC) associated with typical lawn maintenance practices. The potential of SOC sequestration for U.S. home lawns was determined from SOC sequestration rates of turfgrass and grasslands. Net SOC sequestration in lawn soils was estimated using a simple mass balance model derived from typical homeowner lawn maintenance practices. The average SOC sequestration rate for U.S. lawns was 46.0 to 127.1 g C/m²/year. Additional C sequestration can result from biomass gains attributable to fertilizer and irrigation management. Hidden C costs are the amount of energy expended by typical lawn management practices in grams of carbon equivalents (CE)/m²/ year and include practices including mowing, irrigating, fertilizing, and using pesticides. The net SOC sequestration rate was assessed by subtracting the HCC from gross SOC sequestration rate. Lawn maintenance practices ranged from low to high management. Low management with minimal input (MI) included mowing only, a net SOC sequestration rate of 25.4 to 114.2 g C/m²/year. The rate of SOC sequestration for do-it-yourself (DIY) management by homeowners was 80.6 to 183.0 g C/m²/year. High management, based on university and industry-standard best management recommendation practices (BMPs), had a net SOC sequestration rate of 51.7 to 204.3 g C/m²/year. Lawns can be a net sink for atmospheric CO22 under all three evaluated levels of management practices with a national technical potential ranging from 25.4 to 204.3 g C/m²/year. [ABSTRACT FROM AUTHOR]

Turf-grass lawns are ubiquitous in the United States. However direct measurements of land-atmosphere fluxes using the eddy-covariance method above lawn ecosystems are challenging due to the typically small dimensions of lawns and the heterogeneity of land use in an urbanised landscape. Given their typically small patch sizes, there is the potential that CO fluxes measured above turf-grass lawns may be influenced by nearby CO sources such as passing traffic. In this study, we report on two years of eddy-covariance flux measurements above a 1.5 ha turf-grass lawn in which we assess the contribution of nearby traffic emissions to the measured CO flux. We use winter data when the vegetation was dormant to develop an empirical estimate of the traffic effect on the measured CO fluxes, based on a parametrised version of a three-dimensional Lagrangian footprint model and continuous traffic count data. The CO budget of the ecosystem was adjusted by 135gCm in 2007 and by 134gCm in 2008 to determine the natural flux, even though the road crossed the footprint only at its far edge. We show that bottom-up flux estimates based on CO emission factors of the passing vehicles, combined with the crosswind-integrated footprint at the distance of the road, agreed very well with the empirical estimate of the traffic contribution that we derived from the eddy-covariance measurements. The approach we developed may be useful for other sites where investigators plan to make eddy-covariance measurements on small patches within heterogeneous landscapes where there are significant contrasts in flux rates. However, we caution that the modelling approach is empirical and will need to be adapted individually to each site. [ABSTRACT FROM AUTHOR]

Information about the topic discussed at the 2004 annual meeting of the Ecological Society of America in the U.S. It mentions that the focus of the symposium was in reviewing and discussing contemporary understandings of urban soils with particularly on how studying urban soils can contribute to the development and testing of ecological theory. Moreover, the study of urban soil ecology and its relevance to general theory and applied knowledge was also discussed.

Buffalograss [Buchloe dactyloides (Nutt.) Engelm.] is a warm-season grass for low-maintenance lawns. The objective of our study was to assess the genetic variation in 10 accessions of buffalograss obtained from the Chinese Academy of Agricultural Sciences by random amplified polymorphic DNA (RAPD) markers. Fourteen of the 60 primers screened generated 72 highly repeatable polymorphic bands. A dendrogram constructed on the basis of the unweighted pair group method arithmetic average clustering algorithm revealed that nine of 10 accessions formed two distinct clusters. Genetic similarity coefficients calculated from the RAPD data ranged from 0.30 to 0.89 with the lowest value of 0.30 measured between No. 4 and No. 7 from Japan and the United States, respectively. The highest value of 0.89 was measured between No. 6 and No. 8 from the United States and Mexico, respectively. The cophenetic correlation coefficient (r) was 0.92, indicative of a very good fit between the data matrix and the resulting cluster analysis. Principal coordinate analysis (PCO) clearly grouped nine accessions on the two axes with a single accession from the United States that did not cluster with others. The PCO clustering pattern corresponded well with the dendrogram. No. 7 from the United States did not cluster with any other accessions either in the dendrogram or on the basis of the PCO. [ABSTRACT FROM AUTHOR]

Pesticide runoff loads from grass surfaces were estimated for 29 chemicals commonly applied to U.S. lawns and golf courses. Data on pesticide properties and typical application rates and schedules were developed and summarized as input parameters for the TurfPQ runoff model. Weather data for each of 9 U.S. cities were generated by the USCLIMATE model and modified by the addition of growing season irrigation. Simulation runs were made for each chemical, grass surface (lawns, greens, fairways), and city, and the results were summarized as mean annual and 1-in-10 year annual maximum daily pesticide loads. These loads varied greatly with pesticide, grass surface, and city, ranging from 0 to 875 g/ha for mean loads and 0 to 818 g/ha for 1-in-10 year daily loads. Mean annual loads averaged over the 29 chemicals and 3 grass surfaces were found to be closely related to growing season precipitation. Variations among the nine cities were well-captured by three general climate categories: Humid, characterized by abundant precipitation and warm temperatures, represented by Atlanta and Houston; temperate, with moderate precipitation and temperature, as with Albany, Columbus, Madison, and Olympia; and dry, with sparse precipitation, represented by Bismarck, Fresno, and Roswell. Mean annual pesticide runoff was 37, 9, and 2 g/ha in the humid, temperate, and dry regions, respectively. [ABSTRACT FROM AUTHOR]

The spatial variation of productivity across farm fields can be classified by delineating site-specific management zones. Since productivity is influenced by soil characteristics, the spatial pattern of productivity could be caused by a corresponding variation in certain soil properties. Determining the source of variation in productivity can help achieve more effective site-specific management. The objectives of this study were (i) to characterize the spatial variability of soil physical properties across irrigated corn (Zea Mays L.) production fields and (ii) to determine if soil physical properties could explain the variability in productivity between site-specific management zones. The study was conducted over three study sites in northeastern Colorado. The soil properties measured were bulk density, cone index, surface soil color, organic C, texture, sorptivity, and surface water content. A multi-response permutation procedure was used to test for significant differences among soil properties between management zones. Box plots of soil physical properties were created for each management zone within each study site to determine if trends in soil physical properties corresponded to the productivity potential of the management zones. Overall, this study showed that soil physical properties exhibited significant spatial variability across production fields. The trends observed for the measured soil physical properties corresponded to the productivity potential of the management zones. Utilizing site-specific management zones could help manage the in-field variability of yield-limiting soil physical properties. [ABSTRACT FROM AUTHOR]

The article focuses on the outcome of the investigation on lawns, one of the most pervasive and high-input habitat classifications found in suburban residential ecosystem in the U.S. It was estimated that lawn measures between 10 to 16 million hectares in the U.S. and that about 70% of lawns receive fertilisation. In a related matter, it was hypothesized that socio-economic character, yard position and initial condition of the cover were the most influential determinants. The study found that average lawn cover for all yards was 44.6% and that there is a big need to build lawns in front yards. The study has implications for the expanding suburban land use in the urbanised areas of the U.S.

Attempts to investigate the developing definition of curtilage, the area around the home to which the activity of home life extends, and the questions it raises. Graphic evolution of the Fourth Amendment house of privacy in the U.S.; Importance of the curtilage boundary in the war on drugs; Preparedness of the society in recognizing lawn privacy as reasonable.

St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] is utilized in Louisiana and other Southern states for home lawns, and to a lesser extent for commercial lawns. Under moderate management, it provides an adequate stand of turf but when maintained at a higher level it will provide a denser, greener, and better quality stand of turf. There is limited information on the nutrient content of St. Augustinegrass. The objective of this study was to evaluate the responses of both Palmetto and Raleigh St. Augustinegrass under high (H) and low (L) combinations of the following factors: 2 mowing heights (5.0 and 7.5 cm); 2 nitrogen (N) levels (227 and 454 g N 93 m−2 month−1; and 2 potassium (K) levels (227 and 454 g K 93 m−2 month−1). The treatment combinations were (mowing, N, and K), HHH, HHL, HLH, HLL, LHH, LHL, LLH, and LLL. Plots received a micronutrient fertilizer in 06 and 08 and were irrigated as needed. Color, density, texture, uniformity, and quality were determined monthly (04–10). Plant tissue samples were collected and analyzed for macronutrient and micronutrient contents. There were treatment differences for both macronutrients and micronutrients for both cultivars under all treatments. [ABSTRACT FROM AUTHOR]

The presence of clopyralid, a selective broadleaf herbicide, in compost near Spokane, Washington in 2000 was attributed to grass clippings collected from area lawns and subsequently used as compost feedstock. A field study was conducted in 2001 to evaluate the effects of herbicide formulation and mowing practice on the clopyralid content of grass clippings. The objective was to develop guidelines that would limit the concentration of clopyralid in clippings, thereby reducing the amount of clopyralid entering the compost production stream. Clopyralid was applied to turfgrass as either a sprayable (S) or granular (G) formulation. Grass clippings were either collected in a bagging lawn mower and removed from the plots or returned into the plant canopy using a mulching mower designed to finely chop and disperse the leaf blades. Clippings were sampled for a period of ten weeks after application, and again in the summer of 2002, and analyzed for clopyralid content. Mowing treatment had no significant effect on clopyralid content of grass clippings. The S formulation resulted in higher concentration than the G at 4 hours after treatment (193 mg kg[sup-1] and 53 mg kg[sup-1], respectively). At 10 weeks after treatment (WAT), clopyralid concentration averaged 0.9 mg kg[sup-1], and cumulative recovery of clopyralid in grass clippings was 35% and 29% of the amount applied for the S and G formulations, respectively. By 56 and 98 WAT, clopyralid concentration in clippings was 0.06 and 0.02 mg kg[sup-1], respectively. Based on these results, and depending on feedstock dilution and composting conditions, a waiting period of up to one year after application of clopyralid could be necessary for treated grass clippings to be safely used as compost feedstock. [ABSTRACT FROM AUTHOR]

ABSTRACT: Home lawns account for a large portion of the pervious segments of urbanized watersheds. Soil movement and compaction during building construction processes alter soil physical properties, and thus, change hydrologic characteristics of the area. This research quantified the infiltration rates of 15 home lawns in central Pennsylvania and correlated the infiltration rates with selected turf and soil characteristics. Average infiltration rates ranged from 0.4 to 10. 0 cm/hr (0.16 to 3.94 in/hr). Correlations with grass tiller density, soil bulk density, and percentages of sand, silt, and clay were not significant. Excavation procedures and lawn establishment methods appear to affect infiltration of home lawns more than any other factors. [ABSTRACT FROM AUTHOR]

(1) A native Montana grassland was exposed to three-monthly median SO2 concentrations (52, 131, and 228 ,μg m-3) and to nitrogen, sulphur, and nitrogen plus sulphur fertilization. Leaf area of live, dead, and litter production was measured throughout the growing season. (2) SO2 exposures significantly increased leaf area in the 52 μg m-3 SO2 treatment but not in the 134 and 228 μg m-3 treatments. (3) Average number of leaves per plant paralleled live leaf area responses to SO2, emphasizing the balance between fertilization and toxicity rather than SO2-enhanced cell division. (4) With nitrogen fertilization growth increased as the level of SO2 increased, indicating that N fertilization can ameliorate the effects of SO2 pollution. Both rate and time of senescence for nitrogen-fertilized plants exposed to 228 μg m-3 SO2 compared with those exposed to 73 or 134 μg m-3 SO2, but only rate of senescence increased compared with the control. (5) The rate of senescence was more rapid with nitrogen fertilization without SO2 compared with the control. (6) No interaction between soil sulphate and SO2 concentration was observed, even though SO4-fertilizer applications were high. [ABSTRACT FROM AUTHOR]

Focuses on the observational study of the arthropods living in the lawns in State College conducted by graduate student Loren B. Byrne with professors Mary Ann Bruns and Ke Chung Kim in Pennsylvania. Difference between the number of mites in the high-maintenance lawn and control areas; Abundance of ants in the unmown reference areas; Effect of chemical applications and mowing in lawns on many insects.

Suggests that the land at one's front yard can play a role in conservation education. Estimated total area taken up by lawns in the United States; Volume of synthetic fertilizers used in U.S. lawns; Use of chemical pesticides in lawns; Ways of maintaining a biodiversified lawn.