THE GRASSES OF ILLINOIS 



By EDNA MOSHER* 



INTRODUCTION 



According to the earlier botanists who studied the flora of Illinois, 

 about- two hundred species of plants were found on the original prairie 

 and more than half of these were grasses. The grasses were probably 

 the most characteristic plants of the prairie, the shorter and less con- 

 spicuous species forming a dense sod; the taller species usually 

 forming large clumps from three to six feet tall, which were visible 

 for a considerable distance. The original prairie is fast disappearing 

 from the state of Illinois, and with it many of the species of grasses 

 once included in its flora. The majority of the species which were 

 abundant there are still found within the state, altho some of them 

 are extremely rare. A number of the species have not been collected 

 in Illinois in recent years and may not occur in the state at the present 

 time. The grasses, however, still remain a prominent feature of the 

 landscape, as anyone who has seen our great cornfields will testify. 

 From an economic standpoint they are the most important plants of 

 Illinois today, as the cultivated grasses called grains form a large per- 

 centage of the crops of the state. In addition there are the cultivated 

 grasses of our pastures and meadows, many of which are introduced 

 species, and all of which add to the wealth of the state. There are also 

 many species of grasses that are weeds in lawns and cultivated fields, 

 but the extent of their damage never has been, and probably never will 

 be, correctly estimated. 



The known species of grasses of the state have been listed by a 

 number of authors, but the only paper devoted entirely to them was 

 published by I. A. Lapham in 1857. Since then the number of species 

 known to the state has increased nearly fifty percent. Some of these 

 have been included in lists published since that time, but there are 

 forty-three species which have not been listed before as occurring in 

 the state. Some of these species have been introduced from Europe 

 and Asia. Altogether two hundred and four species, representing 

 sixty-three genera, have been listed in this publication. . 



'This work was begun as a secoiul minor under the direction of Professor 

 William Trelease of the Department of Botany while the writer was working for 

 the degree of doctor of philosofjhy in the University of Illinois. Professor Tre- 

 lease urged the completion and publication of the work and has given every aid 

 and encouragement during its progress. Mrs. Agnes Chase has also given valuable 

 assistance, especially as regards questions of synonpny. 



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