and, perhaps, effects of plant (growth environments. It is deemed ■, 

 best to compare seasonal rather than monthly coefficients. 



Seasonal coefficients have been determined for periods 

 when evapotranspiration measurements were made using data shown 

 in Table 5^ and are summarized here as follows: 



Seasonal Alfalfa Coefficients Determined 

 From Measured Periods Only 



Pan Coefficient Atmometer Coefficient 



1939 i960 



0.0125 0.0127 



0.0093 0.0093 



In order to take into account the possibility that the 

 sampling periods could be biased and not representative of groundl 

 cover conditions, and also to include estimated evaporation incre 

 ments following irrigations, estimates of evapotranspiration were 

 made for the irrigation periods. These estimates fill in the misii 

 records. Seasonal coefficients determined from these data are su- 

 marized as follows: 



Seasonal Alfalfa Coefficients, 

 Including Estimated Data 



Pan Coefficient Atmometer Coefficient 



The close similarity between the coefficients determine 

 from the measured periods as compared with the total seasonal 

 period of record, including estimated periods, indicates that the 



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