66 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 17 
line had been pushed 15 to 20 miles west of the river. It is believed 
that westward spread was materially hindered by the greater prevalence 
of westerly winds in this area than farther east and the less favorable 
physical characters, a smaller proportion of woodland and more open 
country, for the development of large infestations, thus making control 
work relatively easy. The winds of the Hudson and Champlain valleys 
are, as shown by figures available, less favorable to westward spread 
than those of the Connecticut Valley, due mostly to the sharper north 
and south valleys in eastern New York and western New England. 
The physical features of the Hudson Valley at least are fully as favorable 
to control work as are those of the Connecticut Valley. The latter is 
not true of the Champlain Valley, though the lake and the adjacent 
higher mountains result in a considerably greater proportion of north 
and south winds and thus materially lessen the hazard of western drift. 
Referring once more to the extension of the quarantined area in 
western Massachusetts, it will be noted that it was much more rapid on 
the eastern slopes of the Berkshires than in the Connecticut Valley or 
east of it. There was apparently a more rapid spread up the hills 
caused in part by the warm winds of spring ascending sunny slopes. 
A similar development may be expected if the Gipsy Moth is allowed to 
establish itself on the eastern slopes of the Catskill and Adirondack 
mountains. Nothing but intense close work from now on can prevent 
this. 
We are confronted by cold realities. It is well known that wind- 
spread is roughly proportional to the amount of infestation. Conse¬ 
quently, in spite of the favorable factors outlined above, it is essential 
that the infestation immediately east of the barrier zone for a distance 
of at least 40 miles in northern New England and 25 miles in the southern 
portion be kept down to a practicable minimum. We are looking to the 
Federal Government as the one agency which should take care of this 
phase of the problem and that early the coming spring. It is admitted 
that New York State has an immediate and compelling interest in pre¬ 
venting the further invasion of her territory by this pest and yet the 
work means similar protection to a very large proportion of the United 
States and the Federal Government therefore is deeply concerned in the 
matter. The maintenance of an exterminative fight over such an ex¬ 
tended front, in a thickly settled prosperous area such as the Hudson 
Valley, is more than one state should attempt and probably more than it 
can be induced to assume for a long series of years without very material 
assistance from some other agency. 
