41 



ern, or "Clover Leaf," Railway, north of Charleston. The south- 

 ern border began just beyond the area of numerous side tracks and ex- 

 tended north of the first east and west cross-road for a distance of 

 about one mile, to the place where the right-of-way is much narrowed 

 and fenced off for cultivation. This is a strip of land through the level 

 black soil area, which was originally composed of dry and wet prairie. 

 The higher portions have a lighter colored soil, and the lower parts 

 have the black and often wet soil which characterized the original 

 swamp or wet prairie. The railway embankment and the side drain- 

 age ditches have favored the perpetuation of patches or strips of these 

 wet habitats ; the excavations for the road-bed, on the other hand, have 

 accelerated drainage of the higher grounds. The soil taken from these 

 cuts and heaped up on the sides of the tracks reinforces the surface 

 relief noticeably in a region which is so nearly level. Through the 

 depressions fillings have been made in building the railway embank- 

 ment, and as a result the drainage has been interfered with in some 

 places. 



The disturbances brought about by railway construction and main- 

 tenance have greatly modified the original conditions, so that the 

 prairie vegetation persists usually only in very irregular areas, some- 

 times reaching a maximum length equal to the combined distance be- 

 tween three or four consecutive telegraph poles — these poles are gen- 

 erally about 200 feet apart. In breadth the area is usually less than 

 the space between the ditch bordering and parallel to the road-bed or 

 embankment and the adjacent fence which bounds the right-of-way, or 

 about 40 feet. This entire right-of-way is about 100 feet wide. In 

 addition to these changes in the physical conditions, a large number of 

 weeds not native to the prairie have been introduced, opportunities for 

 this introduction being favorable, as railways traverse the entire area. 

 In general, attention was devoted solely to the areas or colonies of 

 prairie vegetation and their associated invertebrate animals, the areas 

 of non-prairie vegetation being ignored, not as unworthy of study, but 

 because the vanishing prairie colonies required all the time available. 



I. Colony of Szvamp Grasses (Spartina mid Blymus) , Station I, a 



This colony of slough grass (Spartina tnichauxiana) and wild rye 

 (Blymus) is located a short distance north of the "Clover Leaf" switch 

 tracks and just south of the telegraph pole marked "Toledo 318 miles 

 and St. Louis 133 miles." The length of this colony was about 40 

 paces. 



During August, 19 10, it was dry, but probably in the spring and 

 early summer, rains make this area a habitat for swamp grasses. 



