167 



Notes Upon the Distribution of Forest Trees in 



Indiana. 



Stanley Coultek. 



It is recognized at the outset, that even in a restricted area, such as 

 that under consideration, much of uncertainty is given to any conclusions 

 drawn because of lack of exact data covering every part. The richness of 

 the tree flora in a given county as contrasted with that of adjoining coun- 

 ties, is usually to be explained by the presence of a skilled and persistent 

 worker. It is very certain that no county in tbe State is entirely destitute 

 of trees, in spite of the fact that not a single species may be reported as 

 occurring within its bounds in any published report. 



It frequently happens, also, tbat reports covering certain counties have 

 been based upon the work of untrained observers who have failed to dis- 

 criminate closely related species or who have made incorrect determina- 

 tions, in either case confusing the situation and necessitating a careful 

 revision of the data. While effort has been made to eliminate errors 

 arising from such causes it is more tban probable that some have escaped 

 detection, but in tbe main as regards the species discussed the data seem 

 accurate and complete. 



Of the one hundred twenty -six indigenous species mapped in connection 

 with this study, the larger part by far are probably of general distribution 

 throughout the State. Variation in the density of the stand and in the size 

 and form of individual trees are of course found, but the non-occurrence of 

 any one of the species of this group in any county, under favorable condi- 

 tions, would be more notable than its presence. 



A relatively small group is confined to the extreme northeastern 

 counties of Lake, Porter and Laporte. 



Quite a large group is restricted to the southern counties or tbose 

 lying in tbe first three tiers north of the Ohio River. A peculiar tree flora 

 within this group is that of Posey, Gibson and Knox counties, lying along 

 the lower stretches of the Wabash River. Some of the trees reported from 

 this subdivision no doubt are of wider range than indicated, since few 





