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UNITED STATES DEPARTMENT OF AGRICULTURE 



BULLETIN No. 461 



ii^ „._... „ ........ *j 



Contribution from the Bureau of Plant Industry 

 WM. A. TAYLOR, Chief 



iwrtut. 



Washington, D. C. 



January 19, 1917 



THE IDENTIFICATION OF GRASSES BY THEIR 

 VEGETATIVE CHARACTERS. 



By Lyman Cakrier, 

 Agronomist in Pasture Investigations, Forage-Crop Investigations. 



CONTENTS. 



Page. 



Introduction 1 



What is meant by the term "grass" 2 



Characteristics of grasses before the blooming 



stage 2 



How to use the key in identifying grasses 4 



Analytical key to grass seedlings 6 



Page. 

 Detailed descriptions of forty-eight seedling 



' grasses 9 



Identification of small-grain seedlings 26 



Analytical key to small-grain seedlings 27 



Detailed descriptions of eight small-grain 



seedlings 27 



INTRODUCTION. 



It is often desirable to identify grasses by their vegetative char- 

 acters. The usual botanical classifications based on the structure of 

 the flowering parts are not useful for this purpose. Any mention 

 of the leaves which may be included in botanical descriptions is 

 usually for the purpose of confirming an identification. In lawns 

 and pastures the best grasses are seldom allowed to reach the flower- 

 ing stage, and some grasses change so materially in appearance as 

 they reach maturity that it is difficult to see a resemblance to the 

 young plants in those that have headed. 



There have been previous attempts to work out keys for identi- 

 fying young grasses, especially those of McAlpine, 1 of Ward, 2 and 

 of Percival. 3 Stebler and Schroter 4 have described and illustrated 

 fully the vegetative characters of the most common hay and pasture 



1 McAlpine, A. N. How to know grasses by the leaves. In Standard Cyclopedia of 

 Modern Agriculture, v. 6, p. 153. 1890. 



2 Ward, H. M. Grasses. 190 p., illus. Cambridge, 1901. 



3 Percival, John. Agricultural botany. 798 p., illus. London, 1900. 



4 Stebler, F. G., and Schroter, Carl. The best forage plants. 3 v. in 1, illus., pi. 

 London, 1889. 



61167°— Bull. 461—17 1 



