Insect Losses —- Timber and Forest Products 
Losses of standing timber from attacks by insects are estimated 
at about 950 million cubic feet annuelly. In terms of sawtinber, 
losses are estimated at about l.5 billion board feet. These 
losses reflect the sporadic outbreaks of bark beetles, some 
defoliators, and the less striking endemic losses due to the 
white-pine weevil, wood borers, and other forest insects. In 
monetary terms the loss of standing timber due to insects is 
roughly estimated at about $5 million annually. 
In addition to direct losses of standing timber, there are other 
serious losses as yet unmeasured. Insect attacks lead to reduced 
growth, lowered quality of timber, and destruction of forest ree 
production. Many outbreaks of defoliators may cause little direct 
mortality of trees but reduce their growth rate to a point where 
little wood is produced. Deformities caused by the white-pine 
weevil and increased cull due to damage by boring insects are re- 
flected in lower commercial values of the timber crop. A large 
number of aphids, scales, and other sucking insects feed and in- 
jure trees by removing the plant juices. They cause damage by 
killing trees, reducing wood production, introducing disease 
organisms, or making them susceptible to secondary pests. Un- 
fortunately, little is know of the extent of losses caused by 
these insects, Attack by weevils, evcking insects, and defoliators 
often results in inadequate stocking or complets destruction of 
future growing stocks. Seed and cone insects sometimes destroy 
practically all of a seed crop. The effect of insect injury on 
forest reproduction is not well known. 
Heavy losses of forest products also result from insect attacks. 
From the time a tree is felled until it is finally used in struc- 
tures, equipment, or furniture products, insects take their toll. 
Damage by termites, for example, requires large amounts of lumber 
for repairs and partial replacement. Control costs alone are 
estimated at $75.5 million annually. Many millions of dollars 
are spant in treatments to prevent termite damage. Ambrosia 
beetles and other wood borers attack green logs and lumber, causing 
losses during processing, storage, and usee Pulp logs are subject 
to attack, and heavy losses occur in storage. Powder post beetles 
attack stored lumber, furniture, and other wood products. It is 
estimated from the best information available that approximately 
$10.5 million is lost annually in processing of lumber in manu- 
factured articles and in pulp storage. 
Expenditures for the control of forest insects have averaged 
about $2.6 million annually over the last 10 years. About 75 
percent of these funds have been provided by the Federal Govern- 
ment and the remainder by States and private agencies. 
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