116 



TABLE 33 



WEIGHT OF WATER ABSORBED BY WEEDS DURING THE GROWTH PERIOD RELATED 



TO WEIGHT OF DRY MATTER HARVESTED, AKRON, COLO., 1911-17. 



AFTER SHANTZ AND PIEMEISEL (27) 



Year 



Plants 



1911 

 1913 

 1914 

 1915 

 1916 

 1917 



1911 

 19U 



1911 



1913 

 1916 



1913 

 1913 

 1914 

 1914 

 1912 



1913 

 1916 



1913 

 1913 



1911 

 1912 



1914 

 1913 



Pigweed ( Amaranthus retroflexus ) 



Tumbleweed ( Amaranthus graecizans ) 



Russian thistle ( Salsola pestif er ) 



Lambs quarters ( Ghenopodium album ) 



Purslane ( Portulaca oleracea ) 

 Cocklebur ( Xanthium communeT 

 Nightshade ( Solaniim trif lorum ) 

 Buffalo Bur ( Solanum rostratum ) 

 Gumweed ( Grindelia squarrosa ) 



Sunflower, annual ( Helianthus annuus ) 



Sunflower, narrow leaved 

 ( Helianthus petiolaris ) 



Mountain sage ( Artemisia frigida ) 



Verbena ( Verbena bracteosa ) 

 Fetid marigold TBoebera papposa ) 



1913 Buffalo grass (Bulbilis dactyloides ) 



1914 

 1915 

 1916 

 1917 



1914 

 1916 

 1913 

 1913 

 1914 



Grama grass ( Bouteloua gracilis ) 



Glammyweed ( Polanisia trachysperma ) 

 Iva ( Iva xanthif olia ) 

 Western ragweed ( Ambrosia elatior ) 

 Western wheat grass ( Agropyron smithii ) 

 Franseria (Franseria tenuif olia") 



Water consumed 

 per pound of dry 

 matter harvested 



Pounds 



356 

 320 

 306 

 229 

 340 

 307 



275 

 272 



336 



801 

 666 



292 

 432 

 506 

 557 

 468 



705 

 579 



570 



774 



765 

 474 



730 



881 



308 



389 

 312 

 336 

 290 



502 



652 



948 

 1076 

 1176 



