BOOKS AND CURRENT LITERATURE 



The Water Requirement of Plants. — An interesting and impor- 

 tant study by Briggs and Shantz has lately appeared on the water 

 requirement of plants.^ The research is chiefly of an economic nature, 

 having for its ultimate object the scientific determination of the agricul- 

 tural plants best suited for use oh the Great Plains. The scene of the 

 research is laid at Akron, Colorado, and Amarillo, in the Panhandle of 

 Texas. The rainfall at these stations is relatively small and the evap- 

 oration relatively great, so that the results of such studies as the one in 

 question should be applicable also in a large measure to other semi-arid 

 regions. 



It will not be necessary for the purpose of this note to describe the 

 methods employed or give in detail the work of the investigators. Suf- 

 fice it to state that the methods are probably the most satisfactory yet 

 used where plants are handled on so large a scale. The forms employed 

 were mainly crop species, such as oats, wheat, corn, millet, sorghum, 

 alfalfa, and others, and, in addition, there were three introduced or 

 native plants. The latter were Amaranthus graecizans, A. retroflexus, 

 Artemesia frigida, and Salsola pestifer. Of the wild species, Artemesia 

 is perennial and native to Colorado, occurring in the dry hills. The 

 species of Amaranthus are introduced and, as weeds, have become 

 serious pests. It may be safe to assume that the introduced annuals 

 and the native perennial may be representative of the most successful 

 analogous native species, so far as the water requirement is concerned, 

 which may enable one to extend somewhat the results of the research. 



The line of experimentation followed was the exact determination, 

 under the conditions given, of the "water requirement" of the species 

 studied, which is defined by the authors as "the ratio of the weight of 

 water absorbed by a plant during its growth to the weight of dry matter 

 produced." The water requirement is an inconstant quality, even 

 for the same species. ■ Thus, from the extensive literature list given, 



' Briggs, L. J. and Shantz, H. L. The Water Requirement of Plants. I. In- 

 vestigations in the Great Plains in 1910 and 1911. Bull. 284, Bur. PI. Ind.; II. 

 A Review of the Literature. Bull. 285, Bur. PI. Ind.. 1913. 



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