90 



<^\'y 



^\y^ 



i^ 



^^/A 



::^ 



^^ 



@ Tank I 



n (+ule) 



Pump 



Native 



meadow 



Instrument shelter 



Tank 3 



(native meadow ) 



Ram gage 



^\i/^ 



v\l/^ 



^^l/'^ 



Swamp 



©Tank 2 \ ^ 



(native meadow) ^ 



I — 



^ Anemometer 



Evaporation 

 pan 



SCALE OF FEET 



Al^ 



20 



FIGUEE 10.-- Plan of Parma station, San Luis Valley, Colo. 



Consximptive use data for 1936 are available only for the 

 period June to November, inclusive. Comparison of the October 

 and November consumptive use with loss from a Weather Bureau 

 evaporation pan indicates that all water lost by the tanks during 

 this period was chargeable to evaporation rather than transpira- 

 tion by plant growth. It is apparent that in the high altitudes 

 of San Luis Valley the growing season for native vegetation ends 

 late in September, and transpiration by plant growth is not a 

 factor in ground-water discharge beyond that time. 



