ECONOMIC ENTOMOLOGY. 81 



The Bag Worm (Thyridopteryx ephemerceformis) was at one 

 time very destructive to our park trees, and is still, I am told, in 

 some sections of the country. These can be readily removed with 

 tools in the winter season, and the trees can also be sprayed for 

 their destruction when in foliage. For Tent Caterpillars and 

 others that feed in masses, as Vanessa, Datana, etc., the most 

 effectual method is to remove the mass as soon as they are 

 discovered. If they are very young, a single twig or even a leaf, 

 will be all that it is necessary to take off ; but if left till nearly 

 full grown, they can be taken out by hand, or if on an unimpor- 

 tant branch, this may be cut away with the attached mass. 



For scale insects, many of the emulsions so well known can be 

 applied, and if a pliable steel brush is used in addition, the work 

 can be made very complete, save on the smaller twigs, which can 

 be sprayed with the emulsion as the best means of reaching the 

 insects without destroying the smaller branches. 



For Plant Lice (Aphides) one of the most effectual means is to 

 break up the colonies with a stiff spray of water, for most of 

 them have a gummy secretion that prevents the emulsion from 

 acting upon them, but let the hose be played upon them for a 

 moment, and they are in condition to receive the destructive 

 agent. 



For the Pine Chermes (Chermes pinicorticis) and the Maple 

 Pulviuaria {Pulvinaria inyiumerabilis) ^ I have for a long time been 

 using the spray, and it is the most effectual means of cleauing a 

 tree of these pests. With this spray one can knock down 

 quantities of larvae from the branches, and most eft'ectual work 

 could be done with a steam engine with the proper hose attach- 

 ments in killing great quantities of insects besides keeping many 

 of them in subjection. I would condemn the practice of boring- 

 holes into trees, with the idea that the preparation inserted is 

 going to spread over the whole tree and thereby destroy all kinds 

 of insects ; that is a physical impossibility. We who have charge 

 of plantations of trees are constantly beset by venders of 

 remedies of all kinds that will kill everything but the trees. My 

 advice is, do not waste time and money trying everything that is 

 offered, but consult a physician who is making this a life work — 

 and you have a number of the very best of these in your own 

 state — and his conservative opinion, born of hard practical 

 experience, will be the best advice to follow. 

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