ELM LEAF BEETLE AND WHITE-MARKED '-fUSSpCj^MtrTH, \ 17 



were secured and destroyed at a comparatively slight cost. The 

 defect in this method is that it is more* or less irregular in opera- 

 tion and is usually resorted to only after serious injury to the 

 trees has aroused public opinion. There is no doubt as to the 

 effectiveness of collecting egg masses and in not a few instances 

 it may prove the cheapest method of keeping this pest in 

 check. It would seem better for the welfare of the trees to 

 make some provision for the systematic collection of egg masses 

 from year to year from all the trees, even though the cost be some- 

 what greater. 



The collection of egg masses should be supplemented, if un- 

 cleaned trees are in the vicinity, by banding the trunks at the 

 time the caterpillars begin to crawl, with some material which 

 will prevent the ascent of straggling larvae. A very simple 

 method is to take a band of cotton batting some six or eight 

 inches wide, wrap it around the tree, tie a string about its middle 

 and then turn the upper edge down over the string. Tree tangle- 

 foot, a preparation made by the same company that manufac- 

 tures tanglefoot fly paper, has been used very extensively on 

 trees about Boston. It is very adhesive, remains sticky for a con- 

 siderable time and does not injure the bark of older trees at least. 



The tussock moth caterpillar succumbs readily to arsenical 

 poisons and where the trees are infested or are likely to be at- 

 tacked by more than one leaf feeder, as is true in the Hudson 

 valley, spraying is perhaps the best method of protecting the 

 trees. One of the best poisons for this purpose, particularly in 

 sections infested by the elm leaf beetle, is arsenate of lead, (15 

 per cent arsenic oxid), used at the rate of four pounds to fifty gal- 

 lons of water. 



