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By P.Kandasamy BTE – 06 -014
K= empirical seasonal consumptive use coefficient for the growing season
F= sum of the monthly consumptive use (f) for the growing season
k = empirical consumptive use crop co efficient for the month
f = t x p/100 t = mean monthly temperaturep = monthly daylight hours expressed
as per cent of daylight hours of the year.
CROP M O N T H S
JAN FEB MAR APR MAY JUNE
JULY
AUG SEP OCT NOV DEC
Rice 0.85 1 1.15 1.3 1.25 1.1 0.9
Maize 0.5 0.6 0.7 0.8 0.8 0.6 0.5
Wheat 0.5 0.7 0.75 0.7
Sugar cane
0.75 0.8 0.85 0.85 0.9 0.95 1 1 0.95 0.9 0.85 0.75
Cotton 0.5 0.6 0.75 0.9 0.85 0.75 0.55 0.5 0.5
Vegetables
0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.8 0.7 0.6 0.55 0.5
Citrus 0.5 0.55 0.55 0.6 0.6 0.65 0.7 0.7 0.65 0.6 0.55 0.55
Months Mean monthly temperature, oF (t)
Monthly crop co-efficient (k) from table
Percent day light hrs (p) from table
Monthly consumptive use (inches) k.t.p/100
Jan 77.36 0.5 8.11 3.13
Feb 81.9 0.55 7.4 3.33
Mar 82.67 0.6 8.44 4.18
Apr 88.2 0.65 8.43 4.83
May 90.7 0.7 8.81 5.59
June 89.46 0.75 8.57 5.75
July 88.38 0.8 8.84 6.25
Aug 86.315 0.8 8.74 6.03
Sep 87.215 0.7 8.26 5.04
Oct 84.92 0.6 8.29 4.22
Nov 80.51 0.55 7.89 3.49
Dec 81.41 0.5 8.08 3.28
U= 55.12 inches = 140cm
http://books.google.co.in/books?id=yANwmTjf588C&pg=PA103&lpg=PA103&dq=blaney+criddle+method&source=bl&ots=64j68csYbW&sig=cDIpxuNIWiWntQAqFRbkauXo-YE&hl=en&ei=YvXISZnmIsOGkQWkm4XmAg&sa=X&oi=book_result&resnum=9&ct=result
www.nih.ernet.in/Method3.htm Irrigation theory & practice by A M Michael