167 
Notes Upon THE DISTRIBUTION OF FoREST TREES IN 
INDIANA. 
STANLEY COULTER. 
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 the 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, that 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 than probable that some have escaped 
detection, but in the 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 those 
lying in the 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 
