Table 1.

Parameters for crop ET, precipitation, and irrigation from KanSched2 Irrigation Program, soil type, and corn yield at six site-years: Scandia, 2012, 2013; Topeka, 2012, 2013; Hutchinson, 2013; and Tribune, 2013.

Environment	High ET (>508 mm)				Medium ET (from 432 to 488 mm)				Low ET (<432 mm)
Site-year	Tribune, 2013		Topeka, 2012		Hutchinson, 2013		Scandia, 2012		Scandia, 2013		Topeka, 2013
Soil series†	Ulysses silt loam		Eudora silt loam to sandy loam		Nalim loam		Crete silt loam		Crete silt loam		Eudora silt loam to sandy loam
SWH capacity‡ (mm)	2824		777		937		1059		1059		777
Planting date	6-May		17-April		14-May		22-May		30-April		30-April
Irrigation regime (%ET)	100	50	100	50	100	50	100	50	100	50	100	50
Crop ET§ (mm)	760	579	559	447	488	422	483	483	401	386	417	356
Seasonal Vapor Pressure Deficit (Pa)∗	1261		1375		973		1325		972		924
Precipitation (mm)	404	404	165	165	615	615	203	203	224	224	358	358
Irrigation (mm)	414	193	305	173	102	51	254	127	140	67	229	58
Grain Yield# (Mg ha-1)	13.8	10.4	10.9	9.2	9.7	10.5	12.4	7.8	11.5	10.7	14.2	10.3

Sites were grouped by similar ET values relative to each other, and classified as high, medium, and low. †From USDA-NRCS Web Soil Survey (http://websoilsurvey.nrcs.usda.gov/app/). ‡Estimated from National Engineering Handbook Part 652, Chapter 2: http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_031591.pdf^§Estimated by KanSched for the full irrigation scenario at each location based on reference ET modified by crop coefficients appropriate to vegetative growth, reproductive stage, and senescence growth stages. The ET estimation is across all hybrid by seeding rate treatments within an irrigation regime and does not reflect the ET for individual hybrid by seeding rate treatments. ^∗Vapor pressure deficit (VPD) = ((100 - RH)/100)^∗saturated vapor pressure (SVP), SVP (Pascals) = 610.7^∗10^{7.5 T/(237.3+T)}, Temperature (T). ^#Grain yield is an average of hybrid by seeding rate treatments within an irrigation regime.