INSECT ENEMIES OF EASTERN FORESTS 9 
to be in contact with the ground, and the furniture manufacturer must 
treat his articles to avoid powder-post beetle attack. St. George 
(368), Hopkins (232, 233), Burke (74), and Snyder (389) have pub- 
lished articles on this subject. 
THE RELATION OF INSECTS TO SHADE AND ORNAMENTAL TREES 
The value of shade and ornamental trees in our home grounds, city 
streets, and parks ranks hardly less than that of the homes and build- 
ings themselves. They are so much an integral part of the whole 
property that their protection from insects is as essential as the protec- 
tion of the buildings from fire. Insect attacks have brought about the 
development of trained organizations and elaborate equipment for the 
care of trees. In some sections of the country, particularly the North- 
east and California, the organization of this protective service has 
been elaborately developed, ‘and it is rapidly expanding in other re- 
gions, particularly where large areas are given over to high-class 
residential development. 
THE EFFECT OF INSECTS ON SCENIC AND RECREATIONAL AREAS 
The rapid development in recent years of large areas of State or 
national forests and our national parks for recreational purposes, 
has made it necessary to consider insect outbreaks from a somewhat 
different standpoint than from where only commercial values of the 
forest crop are at stake. 
The importance of the forest cover in national parks, game pre- 
serves, and recreational areas cannot be estimated in monetary values. 
Here the esthetic and protective values far exceed that of the com- 
mercial timber. Although not so directly appreciated by the visitor, 
the forest is one of the greatest attractions in these areas, since much 
of the natural beauty of parks or camp sites is in reality dependent 
upon a green forest cover. ‘Trees are also important in giving protec- 
tion to the birds and other animals. 
The protection of trees on camp grounds from insects is becoming 
very important. These small areas are intensively used, the soil be- 
comes packed and heated by exposure to the sun, roots are exposed 
and injured, the trunks of the trees are damaged, and it is little wonder 
that the trees do not survive the attacks of bark beetles and borers. 
Recently outbreaks of the forest tent caterpillar in the Lake States 
and other places have been of particular importance from an unex- 
pected angle. As defoliation of the trees becomes complete, the cater- 
pillars migrate in great numbers, crawling over and inside buildings, 
getting into food, dropping onto sleeping people, and in general so 
irritating the sensitive temperament of summer tourists as to drive 
them from the locality, much to the regret of local tradesmen and 
resort owners. 
For these reasons the effects of insect outbreaks which mar the scenic 
beauty or destroy the protective value of the forest cover, or interfere 
with its use for recreation, are often more serious than injury to timber 
values. The National Park Service in recognizing this has made it 
