90 BOARD OF AGRICULTURE. [Pub. Doc. 



bounded by Scituate, Brockton, Hudson, Lowell, and Sea- 

 brook, N. H. An isolated colony also occurs at Kittery, 

 Me. As the female moths fly vigorously, this insect spreads 

 much more rapidly than. the gypsy moth, and it seems prob- 

 able that within a short term of years it may occur through- 

 out the entire State of Massachusetts. 



It is fortunate that the insect is exposed in conspicuous 

 webs throughout the winter, thus making its destruction 

 easy. For the work of cutting off the webs the common 

 form of pruning shears attached to a pole is the most con- 

 venient implement. The webs so collected should be care- 

 fully burned at once. Where this work is thoroughly done, 

 there will be no damage by the brown-tail moth the suc- 

 ceeding year. It is remarkable how quickly and at what 

 small expense these webs may be collected and destroyed by 

 trained men, suitably equipped. In the winter of 1899 the 

 employees of the gypsy moth committee gathered and de- 

 stroyed over 900,000 webs, at a total cost of $9,700. 



This work of web destruction is the cheapest and most ef- 

 fective method of disposing of the pest ; but if it is neglected 

 until after the caterpillars leave the web in the spring, the 

 infested trees should be thoroughly sprayed with arsenate 

 of lead. It is also necessary sometimes to spray, to protect 

 the trees from the fall brood. This spraying should be done 

 in September, as soon as the small webs are noticed. In 

 the case of pear and other fruit trees this late treatment will 

 result in the poisoning of fruit approaching maturity. How- 

 ever, it is but a choice between two evils, since, if the tree 

 is defoliated, the fruit will fall before it is ripe. On shade 

 trees there is no valid objection to the fall spraying. 



Turning to our native insects, an important periodic pest 

 of shade trees is the tussock moth ( Orgyia leucostigma, S. 

 and A.). This insect is well known in Boston, Providence 

 and elsewhere, from its severe injuries to elms in certain 

 years. While primarily an elm insect, when numerous it 

 attacks in force the linden, horse chestnut, silver maple, pear 

 and other trees. Its damage is contemporaneous with that 

 of the elm-beetle, and, as it is double-brooded, at least in 

 our river valleys and along the seaboard, it is a shade-tree 



