SPRAYS AND SPRAYING 135 



acre over no spraying. At Cornell Experiment Sta- 

 tion ' one application of Bordeaux mixture, and three 

 of Bordeaux mixture and Paris green, increased the 

 yield 103 bushels per acre, while another" year six 

 sprayings increased the yield 48 bushels per acre. 

 At Vermont Experiment Station 3 two applications 

 have in general proved most profitable. The (N. Y. ) 

 Geneva Experiment Station recommend, as the re- 

 sult of their trials to the year 1904, that spraying com- 

 mence when the plants are 6 to 8 inches tall and 

 thorough applications to be made at intervals of ten to 

 fourteen days during the season, making five to seven 

 applications in all. 



Insecticides are materials used to destroy injurious 

 insects. Poison is spread on the leaves to destroy 

 leaf-eating insects, and materials that kill by contact 

 are used against insects that suck plant-juices. For 

 poisoning the first class there are on the market a 

 number of preparations, which may be grouped as 

 follows: 4 



1. Standard Remedies. Scheele's Green, Paris Green, 



London Purple, Hellebore. 



2. Commercial Substitutes. Paragrene, Green Arsen- 



oid, Green Arsenite, Pink Arsenoid, Laurel 

 Green, Arsenate of Lead, Disparene. 



3. Home-made Remedies. Arsenite of Lime, Arsenite 



of Soda, Arsenate of Lead, Arseuite of Lead. 



4. Proprietary Remedies. Bug Death, 6 Black Death, 6 



Hammond's Slug Shot, 5 Quick Death, Knobug, 



1 (N. Y.) Cornell Bui. 140, p. 402. (N. Y.) Cornell Bui. 196, p. 48. 



Vt Bui. 106. p. 230. * From (N. Y.) Geneva Bui. 243, p. 329. 



s For analysis, see (N. Y.) Geneva Bui. 190, p. 289. 



