544° 
fore they were plowed. Both of these sources of information have their 
limitations. The railway rights-of-way have been subjected to grading, 
artificial drainage, annual cutting, and burning, and many have been culti- 
vated at times. As a result the original associations have been fre- 
quently greatly modified or entirely destroyed. Natural competition is 
interfered with, and the observed composition of the associations and 
habitat-range of individual species may not correspond to original con- 
ditions. It is also of interest in this connection to call attention to the 
fact that patches of natural prairie plants on these rights-of-way may 
not always be relics of the original prairie but the result of secondary 
successions culminating in the original prairie plants. 
This fact is clearly illustrated in many places along the Indianapolis 
branch of the Illinois Central Railway. This right-of-way was originally 
50 feet wide. In 1897 it was made 80 feet wide by enclosing 15 feet of 
farm land on each side. The diagram, Figure 6, represents the suc- 
cession of associations that has occurred on a strip of this abandoned 
farm land near my father’s farm one mile west of Wheeler in Jasper 
county. 
Andropogon furcatus. 
Solidago nemorali Poa pratensis 
Juneus tenuis 
Phleun pratensis Agrostis alba 
Farm weeds 
’ 
Fic. 6. Diagram showing secondary successions on a railway right-of- 
way formerly under cultivation near Wheeler, Illinois. 
At the time of widening the right-of-way the land on one side of 
the tract was a timothy pasture, on the other side it was under culti- 
vation. In some places Andropogon furcatus occurs now in almost pure 
stand and might well be considered original prairie if its history were 
unknown. This reversion to the natural prairie plants may be seen 
anywhere along this right-of-way where a sufficient number of relic 
prairie plants existed on the old right-of-way. Another instance of this, 
on the Baltimore and Ohio Railway in Clay county, is illustrated in 
Plate LXX. The area now covered with Andropogon furcatus was 
formerly forested. The greater part of the 90 miles of this right-of-way 
