6 
preyed upon the elm as to render the advisability of its further 
use as a shade tree in this city extremely doubtful. 
Trees that are regularly and seriously attacked by insects 
difficult to control should not be planted. There are other 
species, among which are some of our most popular trees, that 
require careful and at times expensive treatment if their vigor 
and beauty are to be preserved. Villages and towns not provided 
with spraying apparatus might well abandon these trees and use 
for their principal plantings species less subject to insect attack. 
The tussock moth and a few other caterpillars will, unfor- 
tunately, devour almost any kind of foliage and must receive 
special treatment. Caterpillars that make large webs may be 
easily located and removed by clipping off the branch containing 
the web before the insects are mature. The practice of burning 
them out is usually attended with more or less injury to the tree. 
The eggs of certain caterpillars are deposited in clusters on the 
twigs of trees and may be easily collected and destroyed. The 
tussock moth deposits its eggs on the empty cocoon from which 
ithasemerged. These frothy egg-masses are usually conspicuous 
on the trunks and larger branches of trees during autumn and 
winter, and may either be killed in place by moistening them with 
creosote oil or removed with scrapers and burned. Cocoons 
without egg-masses probably contain parasites and should be 
left undisturbed. In many cities, school children have been 
successfully enlisted in destroying these and other egg-masses. 
Shade trees are often disfigured and at times seriously damaged 
by various appliances and mixtures intended to prevent cater- 
pillars from crawling up their stems. Such methods of destruc- 
tion are rarely effective and their general use should be dis- 
couraged. 
Leaf-eating insects are easily controlled by spraying with 
some poison, like lead arsenate; sucking insects must be covered 
with soap solution or other substance that will interfere with 
their breathing apparatus; while borers must be reached in their 
tunnels with a knife or wire, or some poisonous gas like carbon 
bisulfid. 
W. A. MurrILi. 
