Overseed Performance of Sea Isle 2000 Seashore Paspalum

Abstract

The new Seashore paspalum 'Sea Isle 2000' is being used as a greens surface in many tropical - semi tropical climates were saline water is available for irrigation. While it’s color retention in the fall in Tucson Arizona is good, it still enters full winter dormancy, and requires overseeding with a cool season grass for late fall, winter, and spring play. A two year test was conducted to evaluate the tolerance of Sea Isle 2000 to overseeding, and to evaluate overall turf performance of perennial ryegrass (PR), Poa trivialis (PT) and a mixture of the two when used for overseeding over Sea Isle 2000. PT alone was slow to establish as an overseed in year one, but not in year two. Turfgrass color, quality density and texture were acceptable throughout the test, noting that the 100% perennial ryegrass plot demonstrated a short-term loss of performance during the cold January of 2004. After the initial grow in period, absolute BRD was greatest when growing conditions were less than optimum in mid-winter, and again at the seasons end at the beginning of spring transition (May). This was true in both years. BRD was generally not different between the three overseeding regimes, either when turfs were double mowed prior to BRD measurements, or when a single rolling event was added on the day that BRD was assessed. The 100% PR overseed treatment showed the largest numerical increases in BRD from rolling. This was 6.5 inches in year one and 9.2 inches in year two. Yearly BRD averages of all overseeded surfaces for turfs that were double mowed in year one ranged from 91.5 to 92.4 inches, and in year two from 92.2 to 93.3 inches. Average yearly BRD values among all overseed turfs when rolling was included (including double mowing) in year one ranged from 95.8 to 98.2 inches and from 99.2 to 100.5 inches in year two. Maximum BRD values obtained were 107.8 and 114.3 inches in year one, and 100.0 and 111.1 inches in year two for the mowed only turfs, and mowed and rolled turfs, respectively.