Crop Coefficients for: Wheat Temperature Limits for Growing Degree Day Estimation Upper Limit = 77.0 F Lower Limit = 40.0 F Coefficient and GDD accumulation at the beginning of each growth stage for various maturity groups: STAGE KC Emergence 0.10 0.0 0.0 0.0 Vis. Crown 0.50 115.0 115.0 115.0 Leaf Elong 0.90 230.0 230.0 230.0 Jointing 1.03 518.0 518.0 518.0 Boot 1.10 673.0 673.0 673.0 Heading 1.10 792.3 817.0 836.7 Flowering 1.10 872.7 914.0 947.0 Grain Fill 1.10 1068.3 1150.0 1215.4 Stiff Doug 1.00 1282.9 1409.0 1509.9 Ripening 0.50 1497.5 1668.0 1804.4 Mature 0.10 1640.0 1840.0 2000.0