1907.] PUBLIC DOCUMENT --No. 73. 143 



as more effective in suppressing the moth. A few fruit trees 

 well cared for will yield greater returns at slight expenditure 

 than many trees neglected. 



PRELIMINARY OPERATIONS. 



In the effort to destroy the gypsy moth in a wholesale manner, 

 certain preliminary operations are necessary. These opera- 

 tions in themselves may not involve the actual destruction of 

 the insect, but are required to prepare the way for economical 

 and effective work. If all the trees in the infested district 

 stood apart at suitable intervals, if there was no underbrush 

 in the woodlands or along roadsides, and if there were no hollow 

 and worthless apple trees in orchards, then the combat against 

 the moth would be comparatively an easy matter. But unfor- 

 tunately such ideal conditions can only be found in countries 

 where intensive forestry methods are practiced, and where 

 orchards receive the constant care which is their due. 



Our Massachusetts woodlands are commonly a mass of 

 crowded, choked growth, with ten trees, it may be, struggling 

 for existence where but one can properly reach maturity. Our 

 roadsides are too often but a tangle of brush and vines, - - pic- 

 turesque, it is true, but enormously expensive to clear of moths ; 

 while our orchards, planted generations ago, are as a rule but 

 an aggregation of neglected, unpruned, hollow and diseased 

 trees. These conditions call for much preliminary work before 

 the moth can be fought to advantage, and the principal opera- 

 tions of this class are described below. 



The tendency of nature is to attempt to grow many more 

 trees on a given area of ground than can possibly reach matur- 

 ity, leaving the harsh law of " the survival of the fittest " to 

 crowd and kill out the weaklings, until after the lapse of time 

 only the strongest species and most vigorous specimens survive. 

 A judicious thinning of such woodlands, even up to the time 

 when many of the trees are mature, is of direct benefit to the 

 remaining trees by enabling them to make more perfect growth 

 and reach larger size. 



In combating the gypsy moth in woodlands such thinning is 

 imperative. In the first place, it is impossible to spray to ad- 

 vantage until the trees have been so thinned as to permit the 



