The recommended N rates for St. Augustinegrass (Stenotaphrum secundatum [Walt.] Kuntze.) vary in Florida. This research, conducted in Fort Lauderdale, Citra, and Jay, FL, (2006–2008), aimed to determine the minimum N rate necessary for acceptable St. Augustinegrass and to determine the influence of N and irrigation rate on NO3–N leaching. Urea was applied in Fort Lauderdale, Citra, and Jay at 98, 196, 294, and 588; 49, 196, 343, and 490; and 49, 98, 196, and 294 kg N ha−1 yr−1, respectively, based on best management practices. Irrigation was 2.5 mm d–1 and 13.0 mm three times weekly in Fort Lauderdale; 13 mm twice weekly and 26 mm wk–1 in Citra and Jay. In Fort Lauderdale and Jay, lower than recommended N rates mostly produced acceptable turfgrass. Applications of 196 kg N ha−1 (Fort Lauderdale) and 98 kg N ha−1 (Jay) were the lowest rates producing acceptable turf. In Citra, 65% more N was required for acceptable turf than the recommended minimum . Leaching from all N rates was similar, except when N rates exceeded recommendations or when turfgrass exhibited herbicide stress. The high irrigation rate doubled NO3–N leaching compared to the low rate in Fort Lauderdale; irrigation frequency had no influence on leaching in Citra or Jay. The predicted minimum N rate for acceptable turf in Fort Lauderdale was <98 kg N ha−1 yr−1 (lower than in Citra; more than in Jay). In stressed turf, additional N conferred little benefit to quality and increased leaching.

In Florida, state agencies are concerned about St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] for being a possible high water user and excess (N) applications in home lawns. Th is has resulted in a desire by some municipalities to substitute St. Augustinegrass with bahiagrass (Paspalum notatum Flügge). Consequently, the aim of this study was to determine the eff ect of diff erent N fertilizer rates on water use and turf quality of bahiagrass and St. Augustinegrass commonly used in residential yards. Th e experiment was a split-plot randomized complete block design repeated over two trials. Whole plots arranged in blocks consisted of either bahiagrass cultivar 'Pensacola' or St. Augustinegrass cultivar 'Floratam'. Subplots consisted of two N rates (98 and 294 N kg ha −1 yr −1 ). Water use rates, was infl uenced by grass type and by N rates with bahiagrass having higher water use rates (WURs) than St. Augustinegrass in one of the two trails. Th e high N rate increased turfgrass WURs but only in Trial 1. In both trials clipping yields (CY) were greater for bahiagrass than St. Augustinegrass. Furthermore, the higher N rate produced greater CY than the lower N rate. All treatments produced acceptable turfgrass quality when averaged for each trial though, not for ever cycle. Bahiagrass generally produced superior quality ratings than St. Augustinegrass. In addition, the higher N rate always produced higher quality scores than the lower N rate.

Seashore paspalum (Paspalum vaginatum Swartz) is a warm-season perennial turfgrass commonly used for golf courses that are grown in saline environments or using saline water for irrigation. However, seashore paspalum is also grown in non-saline conditions due to its low fertilizer and water requirements (2). In Barbados, on a newly constructed golf course, seashore paspalum ‘Sea Isle Supreme’ sprigs were imported from Georgia (United States) and were planted over 2006 and 2007 on greens, tees, fairways, and rough. Golf greens were constructed following the United States Golf Association Green Section (Far Hills, NJ) putting green guidelines. Tees and fairways were constructed using native soil. Two years after the grow-in, the putting greens began to exhibit irregular chlorotic patches, followed by gradual thinning and decline of turfgrass stand density in those areas. Additionally, turfgrass roots sampled from those symptomatic patches appeared to be abbreviated compared to non-symptomatic areas of the greens. A survey was conducted in May 2013 to determine if plant-parasitic nematodes were present coinciding with the observed symptoms, which were similar to those described in a previous report (3). Consequently, two samples were collected from each green with a total of four greens sampled. Each sample consisted of 20 soil cores (15 cm depth × 1.2 cm in diameter) from either areas of the greens showing symptoms or from non-symptomatic areas. Nematodes were extracted from 100 cm3 soil samples using a modified centrifugal-sugar flotation technique (4). No plant parasitic nematodes were present in any of the samples from the non-symptomatic areas. Three genera of plant parasitic nematodes were found in all the samples from the symptomatic areas: Helicotylenchus. Mesocriconema, and Pratylenchus. Nematode populations of these genera averaged 30, 60, and 200 nematodes per 100 cm3, respectively. Populations of the genera Helicotylenchus and Mesocriconema were below the action threshold levels for seashore paspalum used by the University of Florida Nematode Assay Laboratory (1). Currently, no threshold exists for Pratylenchus for seashore paspalum. Conversely, the genera Helicotylenchus. Mesocriconema, and Pratylenchus were found associated with the irregular chlorotic patches but not with the non-symptomatic areas. To our knowledge, this is the first report of plant parasitic nematodes associated with seashore paspalum maintained as putting greens in Barbados. References: (1) W. T. Crow. Nematode management for golf courses in Florida. EDIS. Accessed 31 July 2013 from: http://edis.ifas.ufl.edu/in124 , 2001. (2) R. R. Duncan and R. N. Carrow. Seashore Paspalum: The Environmental Turfgrass. John Wiley & Sons, Inc., Hoboken, New Jersey, 2000. (3) A. C. Hixson and W. T. Crow. Plant Dis. 88:680, 2004. (4) W. R. Jenkins. Plant Dis. Rep. 48:692, 1964.

Current best management practices (BMPs) regarding the application of nitrogen (N) to bahiagrass (Paspalum notatum Flügge) in southern Florida are 98 to 196 kg ha−1 yr−1. This range has not been tested to determine if the range adequately produces quality bahiagrass without adversely contributing to nonpoint source additions of N to ground water. The objectives of this research were to determine the N necessary to support acceptable bahiagrass quality by measuring associated color, growth, and nitrate‐N (NO3–N) leaching. Research was conducted from October 2006 to October 2008 in Fort Lauderdale, FL. Nitrogen was applied in 60‐d cycles at rates of 49, 98, 196, or 294 kg ha−1 yr−1 under two irrigation regimes (2.5 mm d−1 and 13 mm three times weekly). Bahiagrass quality and color was acceptable under each N rate during each cycle and regression indicated application of N to bahiagrass was not necessary to produce acceptable turfgrass. Nitrate‐N leaching was unaffected by N rates during each cycle except during Cycle 3 of 2008 when the 196 and 294 kg ha−1 yr−1 led to 93 and 94% greater leaching, respectively, than the 49 kg ha−1 yr−1. The high‐irrigation regime increased NO3–N leaching by as much as eightfold but was not consistent among cycles. If current N recommendations were revised downward (∼49 kg ha−1 yr−1), bahiagrass quality would remain acceptable and the risk of NO3–N leaching would be reduced.