SOAP AS AN INSECTICIDE. 2/1 



their leaves, and at New Canaan several hickory trees were 

 bare the last of September. One of these is shown on Plate IX. 

 Elms, birches, sycamores, and hickories were attacked at Sims- 

 bury and it seemed to make very little difference what the kind 

 of tree. 



The young caterpillars spin a web around two or three leaves 

 and feed within the web, eating away the green portion of the 

 leaf, the frame-work remaining. As the larvae increase in size 

 the entire branch is included in the web and the entire substance 

 of the leaves is devoured, including veins. The fall web-worm 

 is an American species and occurs all over the eastern part of 

 the United States. It is not at all particular as to its food 

 plants, and Howard states that the records of the Division of 

 Entomology show about 120 species of forest, shade, ornamental 

 and fruit trees upon which it feeds.* There are said to be 

 two broods each year south of New York. The writer has 

 not followed out the life-history of the species, but the observa- 

 tions made during 1901 indicate that it was also double-brooded 

 in Connecticut. 



It is an easy matter to remove the nests when small, from 

 fruit trees, by cutting off the ends of the branches. Even this 

 will be unnecessary if the foliage is kept well poisoned until 

 late in the season. 



COMMON SOAP AS AN INSECTICIDE. 



It has long been known that soap-suds are useful in destroying 

 plant lice, and the housewife as well as the gardener and florist 

 has used them on plants with success. Our experience with 

 soap as an insecticide began in the greenhouse by using "Ivory" 

 soap, one-fourth pound dissolved in one gallon of water, and 

 applied to chrysanthemums to kill black lice, to Ageratum to 

 destroy Aleyrodes or white fly, to carnations to kill red spider, 

 and to cinerarias, Hibiscus and cigar plant (Cuphea) to kill 

 green lice. Whether the plants were dipped or whether the 

 suds were applied as a spray, they destroyed the insects, but 

 some of the plants were injured. 



The mixture was then diluted one-half, and on January I2th 

 all the carnation plants were sprayed to kill red spider, with 

 satisfactory results. Wherever the spray came in contact with 



* Farmers Bulletin, No. 99, p. 20, U. S. Department of Agriculture. 



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