432 CONTROLLING INSECTS AND PLANT DISEASES 



15. Killing San Jose Scale. Dilute a part of the concentrated lime-sulfur 

 solution and use as a spray on San Jose scale or other scale insects in a winter 

 condition. Some weeks later, the sprayed plants should be examined to see 

 if any insects have survived. 



16. Self-boiled lime-sulfur should be made up in the laboratory, using 

 a large enough quantity to produce the heat necessary for the boiling. Label 

 the stock solution, indicating the strength, and save for future use. 



17. Make up a solution of the self-boiled lime-sulfur to use as a summer 

 spray, and apply it to peach trees or plum trees to prevent plum rot and to 

 kill any young scale insects present. 



18. Other Spray Materials. Make up preparations of each of the other 

 materials mentioned as insecticides and fungicides. If possible, use each of 

 these materials and note their effects. 



19. Spray Nozzles. If possible, make a collection of spray nozzles of 

 different types, and study the merits and demerits of each. ^ 



20. Spraying machines if used in the vicinity, should be visited and studied 

 with reference to their adaptation to the work expected of them. 



QUESTIONS 



1. How may good farm management aid in the control of insect enemies and 



plant diseases? 



2. Give an illustration of the value of planting at the proper time. 



3. Explain the value of rotation of crops in this regard. 



4. What is the influence of volunteer plants and weeds in the spread of 



insects and plant diseases? 



5 Why should we try to force a rapid growth where insect enemies are 

 present? 



6. Explain the importance of cleaning up after each crop. 



7. How does fall plowing help to control insects? 



8. Give an example of a trap crop and explain its use. 



9. Why is prevention more important than ''cure' in the control of plant 



diseases? 



10. For what type of insects are the arsenical poisons used? And for what are 



the contact insecticides used? 



11. Discuss one of the arsenical spray materials. 



12. Describe how to make, test and use concentrated lime-sulfur. 



13. Give directions for making self -boiled lime-sulfur solution. 



14. For what is it used? 



15 Tell how to make kerosene emulsion and give its uses. 



10- Give directions for making Bordeaux mixture. 



17. For what may combined spray materials be -used? Give several examples. 



18. Give the chief principles of spraying. 



References. United States Farmers' Bulletins: 127. Important Insec- 

 ticides; 172, Scale Insects and Mites on Citrus Fruits; 196, Usefulness of the 

 American Toad; 219, Lessons from the Grain Rust Epidemic of 1904; 231, 

 Spraying for Cucumber and Melon Diseases; 243, Fungicides and Their Uses 

 in Preventing Diseases of Fruits; 247, The Control of the Codling Moth and 

 Apple Scab; 284, Insect and Fungous Enemies of the Grape East of the Rocky 

 Mountains ; 440, Spraying Peaches for Control of Brown Rot, Scab, and Curculio ; 

 456, Our Grosbeaks and Their Value to Agriculture; 488, Diseases of Cabbage 

 and Related Crops and Their Control ; 506, Food of Some Well-known Birds 

 of Forest. Farm, and Garden; 564, The Gipsey Moth and Brown-tail Moth 

 With Suggestions for Control; 595, Arsenate of Lead Against the Tobacco 

 Hornworm; 609, Bird Houses and How to Build Them; 621, How to Attract, 

 Birds in Northeastern United States; 630, Common Birds Useful to the Far- 



