Oct. 15, 1914 



Water Requirement of Plants 



13 



BARLEY 



Barley is the most uniform in water requirement of the small-grain 

 crops which the writers have tested. The four varieties grown at Akron 

 in 1 91 2 showed only slight differences in their water requirement. The 

 results obtained, based upon the production of dry matter, were as follows : 



Variety of barley Water requirement 



Beardless 403 ±8 



Beldi 4i6±4 



White Hull-less 439 ±1 



Hannchen 443 ±3 



These same varieties were also tested at Akron in 191 1 and were 

 found to be in practical agreement as regards their relative water require- 

 ment. The mean value of the water requirement was 27 per cent 

 higher in 191 1 than in 1912. 



The results obtained with barley when the water requirement is 

 based on grain production are less uniform than when the total dry mat- 

 ter is employed. Reference to Table VII will show that this is often 

 due to a single pot which for some reason fails to set grain as abundantly 

 as the rest of the series. The Beldi, a dwarf variety, showed the highest 

 efficiency in the use of water in grain production. The White Hull-less 

 (PI. Ill, fig. 2) has a water requirement slightly above the other 

 varieties, even when a correction is made for the naked character of 

 the grain. 



Table VII. — Water requirement of different varieties of barley at Akron, Colo., in IQ12 



