64 The Spraying of Plants. 



a single injured apple. Other apple trees, only a few rods dis- 

 tant, which were not treated with the poisonous liquid, are 

 bearing fruit, one-fourth to one-half of which is 'wormy.'" 1 

 This is probably the first experiment made by an entomologist 

 for the control of the codlin-moth by the use of an arsenical 

 compound. Still, scientists were slow to recommend the use 

 of the poison. The year following, Cook said : "I have been 

 very successful in the use of Paris green, and others have, and 

 for myself I would not hesitate to use it, but some of our best 

 entomologists consider there is great danger in the use of this 

 poison, and I prefer not to be put on record as recommending 

 it for others' use. I used the poison on my own trees, and shall 

 not hesitate to do so again." 2 Woodward at the same time 

 said that the remedy was regularly used in western New York, 

 where "two men will spray one hundred trees in half a day, 

 . . . and I have yet to learn of a single instance where any one 

 has been injured by the use of the poison." 



Notices of this work appeared in most of the leading agri- 

 cultural papers. Yet comparatively little was heard of the use 

 of Paris green for the destruction of the codlin-moth during 

 the next few years. Orchardists seemed to hesitate in apply- 

 ing the poison for this insect, although it was quite freely used 

 for the canker-worm. But very few of the most progressive 

 men adopted the method, with apparently satisfactory results. 

 After the establishment of the experiment stations, in fulfill- 

 ment of the requirements of the Hatch bill of 1887, a new 

 impetus was given to the adoption of the arsenites. As differ- 

 ent experimenters published the results of their work, the value 

 of the practice became more generally known, and gradually an 

 ever-increasing number of growers accepted the assistance of 

 the arsenites in the production of perfect fruit. 



For several years after the discovery of the successful treat- 

 ment of the canker-worm, recommendations regarding the 

 destruction of other foliage-eating insects were more freely 

 made than adopted. In the report of the United States Depart- 

 ment of Agriculture for 1878, C. V. Riley recommended the 

 use of Paris green for the destruction of the following insects : 

 Chapin's apple-leaf sewer, the thick-thighed walking stick, the 

 imported elm-leaf beetle, the juniper web-worm, and the apple 



* Rept. Mich. Pom. Soc. 1880, 136. * Ibid. 1881, 130. 



