● July–September 2003 13(3) 500 RESEARCH REPORTS niella occidentalis (Perg.) (Thysanoptera: Thripidae) on ornamentals. Bul. Intl. Org. Biol. Control/West Palearctic Reg. Sect. (IOBC/WPRS) 16:78–81. Gillespie, D.R. and R.S. Vernon. 1990. Trap catch of western flower thrips (Thy- sanoptera: Thripidae) as affected by color and height of sticky traps in mature green- house cucumber crops. J. Econ. Entomol. 83:971–975. Heinz, K.M., M.P. Parrella, and J.P. New- man. 1992. Time-efficient use of yellow sticky traps in monitoring insect popula- tions. J. Econ. Entomol. 85:2263–2269. Hsu, C. and W. Quarles. 1995. Greenhouse IPM for western flower thrips. The IPM Practitioner 17(4):1–11. Lublinkhof, J. and D.E. Foster. 1977. Development and reproductive capacity of Frankliniella occidentalis (Thysanoptera: Thripidae) reared at three temperatures. J. Kan. Entomol. Soc. 50:313–316. MacDonald, O.C. 1993. Susceptibility of western flower thrips, Frankliniella oc- cidentalis (Pergande) to fumigation with methyl bromide. Ann. Appl. Biol. 123: 531–537. Nyrop, J.P., M.R. Binns, and W. van der Werf. 1999. Sampling for IPM de- cision making: Where should we invest time and resources? Phytopathology 89: 1104–1111. Parrella, M.P. 1992. Set pest thresholds with yellow sticky cards. GrowerTalks 56(7):93. Pearsall, I.A. and J.H. Meyers. 2001. Spatial and temporal patterns of dispersal of west- ern flower thrips (Thysanoptera: Thripidae) in Nectarine orchards in British Columbia. J. Econ. Entomol. 94:831–843. Robb, K.L., J. Newman, J.K. Virzi, and M.P. Parrella. 1995. Insecticide resistance in western flower thrips, p. 341-346. In: B. L. Parker, M. Skinner, and T. Lewis (eds.). Thrips biology and management. Plenum Press, New York. Sadof, C.S., and D.C. Sclar. 2002. Public tolerance to defoliation and flower distor- tion in a public horticulture garden. J. Econ. Entomol. 95:348–353. SAS Institute. 2002. SAS System for Windows, version 8.1. SAS Institute, Cary, N.C. Shipp, J. L., and N. Zariffa. 1990. De- veloping a sampling program for western flower thrips on greenhouse peppers. Bull. International Organization for Biological Control/West Palearctic Regional Section (IOBC/WPRS) 8(5):194–197. Shipp, J.L. and N. Zariffa. 1991. Spatial pat- terns of and sampling methods for western flower thrips (Thysanoptera: Thripidae) on greenhouse sweet pepper. Can. Entomol. 123:989–1000. Sites, R.W. and W.S. Chambers. 1990. Initiation of vernal activity of Franklini- ella occidentalis and Thrips tabaci on the Texas south plains. S.W. Entomol. 15(3): 339–343. Wawrzynski, R.P., M.E. Ascerno, and M.J. McDonough. 2001. A survey of biological control users in Midwest greenhouse opera- tions. Amer. Entomol. 47(4):228–234. Evaluation of Five Methods for Estimating Class A Pan Evaporation in a Humid Climate Suat Irmak 1 and Dorota Z. Haman 2 ADDITIONAL INDEX WORDS. irrigation scheduling SUMMARY. Evaporation pans continue to be used extensively throughout the world to measure free-surface water evaporation (E pan ) and to estimate evapotranspiration for irrigation scheduling and water management for agronomic and horticultural crops. E pan is also being used extensively to estimate evaporation rates from lakes, wetlands, rivers, reservoirs, and other water bodies for management of wildlife and ecological habitat. A reliable method is needed to estimate missing daily E pan data. Determination of a reliable method for the estima- tion of E pan would also be useful in modeling of crop growth, and hydrological and ecological systems. Five methods [Penman (Penman, 1948), Kohler-Nordenson-Fox (KNF) (Kohler et al., 1955), Christiansen (Christiansen, 1968), Priestley-Taylor (PT) (Priestley and Taylor, 1972), and Linacre (Linacre, 1977)] for estimating E pan were compared with the historical (23-year) measured daily values to determine the suc- cess of accurate and consistent E pan estimations under humid climatic conditions in Florida. The root mean square error (RMSE) was used as the criteria to judge the accuracy and reliability of a given method. An RMSE value of <0.5 mm·d –1 (0.02 inches/d) between the measured and estimated E pan was considered as an acceptable error for daily estimations. The standard deviation (SD) values, and percent error (%E) between the estimated and measured values were Florida Agricultural Experiment Station journal series R-07895. 1 Department of Agricultural and Biological Engi- neering, University of Florida, 234 Frazier Rogers Hall, P.O. Box 110570, Gainesville, FL 32611. To whom reprint requests should be addressed; e-mail sirmak@mail.ifas.ufl.edu. 2 Department of Agricultural and Biological Engi- neering, University of Florida, Rogers Hall, P.O. Box 110570, Gainesville, FL 32611.