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The pine Ghermes {Ghermespinicorticis) is another insect that is giving 

 us a great deal of trouble, but we can subdue it most effectually with 

 a stilf spray. The tree is then treated with the kerosene emulsion, and 

 also those insects collected or washed down around the base of the tree. 

 This has to be done at least three times a year. For the past seven 

 years I have been using the stiff spray for different work, and it is one 

 of the best means I know of for cleaning maples of Pulvinaria. Three 

 years ago Pulvinaria innumerahilis was very abundant on a great 

 number of trees in our parks, and I treated them with the hose and 

 emulsion until I had them in fair subjection. The Chermes and Pulvi- 

 naria were at one time taken off with corn brooms, but the spray is 

 much more effectual, and gets in among the small twigs without break- 

 ing them. 



Scale insects are treated with washes and taken off with steel brushes, 

 and are also sprayed with an emulsion, which covers the smaller 

 branches. Eriosoma rileyi is common on our young elms, and these are 

 treated with the kerosene and carbolic emulsion. 



The larvae ot the larger silk producers are collected and destroyed, 

 as well as the cocoons. Datanas are collected by hand, as they are 

 assembled in masses, and destroyed. The web- worm, always abundant 

 in our parks, is collected either by taking down the twigs or, if the tree 

 is a valuable one, by twisting them out and crushing the larvse. 



Alypia oetomaculata is abundant where Ampelopsis is grown. These 

 are effectually destroyed with the London purple solution. 



The catalpa trees have been affected by a species of Cecidomyia, which 

 causes the ends of the branches to turn black and break off". These 

 are collected every year and destroyed before the larvne leave the twigs. 

 Leaf-skeletonizers are always abundant on many of our trees, and the 

 Platanus and Liquidambar species have suffered most. These insects 

 are cut off as soon as they can be seen working and destroyed. If left 

 for any length of time they make the tree very unsightly. 



Aphis species are treated with the kerosene emulsion after the colo- 

 nies have been broken up with the stiff" spray. I have found it impossible 

 to get an emulsion to act upon many of the plant-lice on account of the 

 secretion; but let me play the hose on them a short time and they are 

 disintegrated and demoralized, and many are killed outright by the 

 shock ; then a fine spray of emulsion will reach them more effectually 

 than otherwise. The more I have occasion to use a force of water the 

 more I see the benefits that will accrue from it, especially in economic 

 entomological work, for larva? of many kinds can be knocked down by 

 it, and my men have brought me birds that they have knocked out of 

 a tree and captured. 



Other insects that are working on the foliage and in the stems of our 

 plants we have in great numbers, but enough has been said to give an 

 idea of some of the work we try to accomplish. Could we have suf- 

 ficient force to do the work at the proper time there seems to be no 



