Water Requirements of Newly Established Cool Season Turfgrass Species as Influenced by Mowing Height and Nitrogen.

Water use restrictions are continuing to have an impact on the way turf is managed today and will be managed in the future.  The objective of this research was to evaluate the irrigation requirements of ten newly established cool-season turfgrass species maintained under two different mowing height and nitrogen fertility regimes.  The site was treated with glyphosate to eliminate existing plant material, scalped to remove foliage, leveled, and graded to provide adequate surface drainage.  All plots were seeded with a blend of 3 cultivars for all turfgrass species (Kentucky bluegrass, perennial ryegrass, velvet bentgrass, creeping bentgrass, colonial bentgrass, strong creeping red fescue, chewings fescue, slender creeping red fescue, tall fescue) except for annual bluegrass which was sodded.  Plots were mowed at 1.6 and 5.1 cm three times and one time per week respectively.  Nitrogen was applied at either 49 kg/ha/yr or 195 kg/ha/yr.  Water moisture stress was assessed visually as well with a TDR moisture probe at a 3.8 cm depth for a 45-day period in 2009.  Irrigation was applied based on predetermined water replacement values through a hand-held hose with a flow and batch meter attachment.  The average irrigation inputs for each species ranged from 29.24 L per 13 m² (annual bluegrass) to 13.06 L per 13 m² (tall fescue) for the duration of the trial (45 days).  Significant irrigation input differences were observed between mowing height treatments but not among nitrogen fertility treatments.  By establishing irrigation input quantities turf managers will have the ability to select turfgrasses and to ensure the plants are receiving adequate moisture during the initial year of establishment to maintain sufficient vigor to provide satisfactory playing conditions.