studies that turfgrass evapotranspiration rates increase with increasing N fertilization, a relationship often attributed to changes in leaf elongation rate and/or the amount of transpiring leaf area exposed to the atmosphere between mowings ( Ebdon et al
Benjamin Wherley and Thomas R. Sinclair
M.J. Hattendorf and J.R. Davenport
Cranberry (Vaccinium macrocarpon Ait.) evapotranspiration (ET) has not been documented. Micrometeorological techniques based on canopy temperature minus air temperature were used to estimate ET on `Stevens' and `Crowley' cranberry at Long Beach (lat. ≈46°20′N, long. 124°W) and Grayland (lat. ≈46°47′N, long. 124°W), Wash., in 1991 and 1992, respectively. Cranberry ET was 55% of Priestley–Taylor reference ET and ranged from <0.5 to >4 mm·d–1. The Priestley–Taylor reference ET was a very good predictor of cranberry ET (r 2 = 0.795). Running 7-day cumulative ET ranged from 7 to 17 mm·week–1.
Lee F. Johnson, Michael Cahn, Frank Martin, Forrest Melton, Sharon Benzen, Barry Farrara and Kirk Post
crop canopy, and exerts a direct influence on energy exchange at the land surface that drives the evapotranspiration process ( Allen et al., 1998 ). As such, estimates of Fc can provide a basis for Kc and crop ET (ETc) monitored in vegetables ( Bryla et
Eric W. Kerschen, Caleb Garten, Kimberly A. Williams and Melanie M. Derby
water vapor emission from foliage) and evaporation (conversion of water to vapor at the surface of root medium), the combination of which is evapotranspiration. Many low-light plant species can grow indoors under existing lighting conditions ( DelPrince
George C.J. Fernandez and Belinda Love
Twenty-five commercially available turfgrass cultivars were evaluated for cumulative evapotranspiration (ETcum) attributes under progressive water stress for 0 to 21 and 0 to 24 days using the gravimetric mass balance method in two greenhouse studies. At the end of the water-stress treatment, the cultivars were scored visually for their green appearance on a 0 (no green) to 10 (100% green) scale. The Gompertz nonlinear model gave a best fit to ETcum vs. days adjusted for pan evaporation variation in the greenhouse compared with monomolecular and logistic nonlinear regression models. Two ETcum attributes—maximum evapotranspiration rates (ETmax) and inflection time (ti) (the time when the change in ET becomes zero)—were estimated for each cultivar using the Gompertz model. Based on final ETcum, ETmax, ti, and greenness score, `Bristol', `Challenger', and `Wabash' Kentucky bluegrass (Poa pratensis L.); `Shademaster' creeping fescue (Festuca rubra L.); `FRT-30149' fine fescue (F. rubra L.); and `Aurora' hard fescue (F. ovina var. duriuscula L. Koch.) were identified as low water-use cultivars.
Richard C. Beeson Jr.
). Early work by Burger et al. (1987 ) and Regan (1997) calculated crop coefficients (Kc) to relate woody plant actual ET A to Penman-Montieth-based reference evapotranspiration. However, these Kcs were based on a fixed value of container surface area
Giovanni Piccinni, Jonghan Ko, Thomas Marek and Daniel I. Leskovar
further developed by the other researchers ( Allen et al., 1998 ; Burman et al., 1980a , 1980b ; Doorenbos and Pruitt, 1977 ). K C is the ratio of the evapotranspiration of the crop (ET C ) to a reference crop (ET O ) ( Allen et al., 1998 ). ET O may
Richard C. Beeson Jr. and Jianjun Chen
estimating ET A of container-grown woody ornamental plants as a basis for precision irrigation. Based on the relationships of ET A , potential evapotranspiration (ET O ), and projected canopy area (PCA) of a given species, a water need index (WNI) or plant
Jeff B. Million, Thomas H. Yeager and Joseph P. Albano
not included in the overall analysis of irrigation and runoff during the two experiments. Irrigation, evapotranspiration, and plant capture factor. Plants were irrigated predawn (usually at 0500 hr ) with either a fixed rate of 1 cm·d −1 of water (1
Harold McCutchan and K.A. Shackel
Abbreviations: ET, evapotranspiration; ψ, water potential; VPD, vapor pressure deficit. 1 UC Cooperative Extension, 733 County Center III Court, Modesto, CA 95355. This work supported in part by a grant from the California Prune Board. The cost of