INSECT DEPREDATIONS FN NORTH AMERICAN FORESTS. 75 



officer should be furnished with instructions for the Location of beetle- 

 infested trees, and with equipment and directions for taking the 

 necessary action whenever the condition- demand or warrant it. 



In private forests. — Private forests should receive the same atten- 

 tion as public forests, but this is often far more difficult on account 

 of intervening forests, where the owners either can not or will not 

 give the matter the required attention. While it may be advisable 

 to have some laws to govern the treatment of timber infested with a 

 dangerous pest, when the owner refuses to take any action such a 

 law should apply only to the more extreme cases or as a last resort 

 on authoritative advice. It is probable that in most cases legislation 

 will not be necessary, and more ultimate good will result without 

 than with strict laws, especially when it can be made clear to the 

 owner that his personal interests demand that he take the proper 

 action and that, when necessary, his neighbors will render assistance, 

 as is done in the case of a forest' fire. 



Inaccessible areas. — There are yet large inaccessible areas in the 

 East and West where it is not practicable or possible at present to con- 

 trol the depredations by these beetles and which must therefore be 

 left to the same natural adjustment that has been going on in all for- 

 ests from their beginning. While under such natural control much 

 of the older matured timber will be lost it will usually be replaced 

 by young growth, either of the same species of trees or of a different 

 species, so that under normal conditions the forest will be perpetu- 

 ated : but tinder exceptional conditions and combinations of detri- 

 mental influences, such as secondary insect enemies, fire, drought, etc. 

 extensive areas may be completely denuded, never to be refore>ted 

 under natural conditions. Therefore it will evidently not be very 

 long before it will pay to adopt insect-control policies even in the 

 areas that are inaccessible for profitable lumbering. 



Examples ok Successful Control ok Babkbeetles. 



AVe have a sufficient number of examples of successful control of 

 depredations by the destructive barkbeetles to demonstrate the prac- 

 ticability of the advice based on the results of recent entomological 

 investigations. 



Control of the eastern 8pruc( beetle. — The control of an alarming 

 outbreak of the eastern spruce beetle (Dendroetanus piceaperda 

 Ilopk.) in northeastern Maine in L900 and L901 was effected by the 

 concentration of regular logging operations into the areas of infested 

 timber and placing the logs in Lakes and streams and driving them 

 to the mills on the Androscoggin River. Thus, with little or no addi- 

 tional expense, there was a saving to one firm, according to its esti- 

 mates, of more than S100.000. 



