Development of the Vegetation of New York State 183 
off into the air to permit more than a dry land or xerophytic 
vegetation or at any rate a more tolerant vegetation than the 
associated species of the climax forest." 
I take it that this condition of the moisture relation ac- 
counts quite as much for the success of Polytrichum, bracken 
fern, blueberry patches, raspberry thicket and the forest- 
weed species of aspen, fire cherry and white birch as the fac- 
tor of soil acidity or the earlier seeding by these species 
rather than maple, beech, yellow birch, hemlock and white 
pine. 
Tn all these cases the practice of afforestation by planting 
will have to take account of this essentially more arid condi- 
tion of the land than prevails in the natural habitat of some 
or most of the species which it is sought to plant. The nat- 
ural sequence of vegetation upon such lands or in any case 
leading to climax forest may prove to be a most useful sug- 
gestion to the forester. 
There grows out of all this also the obvious suggestion that 
a lot of questions have arisen which can be solved only by 
scientifically conducted investigations. 
Conclusion. 
It will have become obvious to anyone who has read any 
considerable portion of this bulletin that it represents the 
method of the teacher rather than the output of an investi- 
gator. ‘The bulletin will in fact have accomplished its pur- 
pose if it proves effective in leading the reader to take a cer- 
tain viewpoint from which to regard the vegetation of his 
State and particularly if it should stimulate further and 
more detailed studies of it and, in a measure at least, point 
out where these fields of investigation lie and what may be 
expected as the outcome of them. 
As to the viewpoint, it is simply to keep in mind the whole 
forward movement — the dynamics — of the plant life of the 
1In this connection, see Pearson, G. A. The Role of Aspen in the 
Reforestation of Mountain Burns in Arizona and New Mexico. The 
Plant World, 17:1914, pp. 249-260. 
