Crop Coefficients for Tall Fescue and Hybrid Bermudagrass in the Transition Zone. Issue 1 (1st July 2019)

• Record Type: Journal Article
• Authors: Pinnix, Garland D.; Miller, Grady L.
• Is Part Of: Crop, forage & turfgrass management. Volume 5:Issue 1(2019)
• Page Start: 1
• Page End: 7
• Publication Date: 2019-07-01
• Subjects: Crop science -- Periodicals; Agronomy -- Periodicals; Forage -- Periodicals; Turf management -- Periodicals; Agronomy; Crop science; Forage; Turf management; Periodicals; Electronic journals; 633
• DOI: 10.2134/cftm2019.02.0013
• Languages: English
• ISSNs: 2374-3832

Abstract

Abstract : Core Ideas: The use of historical and current weather data is an economical alternative for scheduling landscape irrigation. Standard suggested crop coefficients of 0.8 (cool‐season) and 0.6 (warm‐season) will often result in overwatering in the transition zone. When using historical weather data to schedule landscape irrigation, locally‐derived crop coefficients should be used to increase efficiency. Accurate turfgrass crop coefficients are critical when scheduling irrigation based on reference evapotranspiration (ET o ). Currently, locally derived turfgrass crop coefficients are lacking in the transition zone. The objective of this field study was to derive crop coefficients ( K c ) for 'Triple Threat' tall fescue ( Festuca arundinacea Schreb.) and 'Tifway' hybrid bermudagrass [ Cynodon dactylon (L.) Pers. × Cynodon transvaalensis Burtt‐Davy] managed in the transition zone. Direct measurements of actual evapotranspiration (ET a ) were made through the weighing of lysimeters planted with tall fescue and hybrid bermudagrass. Data were collected from May through October of 2017 and 2018 from nonstressed turfgrass. Turfgrass crop coefficients were computed by the quotient of ET a and ET o, calculated from the ASCE‐Standardized reference evapotranspiration equation using meteorological data collected from an on‐site weather station. Tall fescue and hybrid bermudagrass K c varied by month ( P < 0.0001). Means for tall fescue and hybrid bermudagrass K c ranged from 0.69 to 0.85 (± 0.16 SD) and 0.44 to 0.59 (± 0.10 SD), respectively. Tall fescue K c exceeded hybrid bermudagrass every month as the result of higher ET a . The use of locally‐derived turfgrass crop coefficients can assist turfgrass managers in the transition zone to better meet turfgrass water demands.