THE TEACHING OF AGRICULTURE 7 



Let school holidays and perhaps other days be filled with 

 historical or agricultural or other pageants suitable to the 

 season; have appropriate contests, school games, and good 

 sports. Let there be recreational diversion for old and young. 

 Appoint committees to cooperate in preparing for these 

 occasions. 



Problems. A few problems here will be suggestive and serve as 

 sample problems to be placed on the board for pupils, from time to time. 



1. Calculate the number of cabbages on an acre if they are set as 

 close as shown in Appendix, Table XII, allowing for one-fourth loss. 



2. If cabbage worms destroy one-third of the above result, and the 

 good heads bring 5 cents per head, what is the income for the acre? 



3. What would be the money value of the heads destroyed by 

 cabbage worms? 



4. If a boy working at $1 per day can dust three acres of cabbage 

 plants a day and keep off the worms, what is the profit for his day's 

 work, if the material costs 90 cents? 



5. A man has 500 young apple trees attacked by woolly aphis 

 insects, which he wishes to spray with kerosene emulsion to save the 

 trees. If six gallons of the stock solution given in Appendix, Table III, 

 are required (diluted with ten parts water), calculate the cost of mate- 

 rials at present local prices for soap and kerosene. 



6. If the use of the sprayers is worth SI and the labor can be done 

 by two men in a day and a quarter, what is the total cost cf the 

 spraying job? 



7. If a pair of bluebirds, in seeking food for their young in the nest, 

 gather 120. worms from an old orchard each day, and each worm is 

 thereby prevented from doing five cents' worth of damage to fruit, 

 calculate the value of these birds in one nesting season of sixteen days. 



8. A solitary wasp collected for her brood thirty-eight apple 

 worms, and thus prevented each of these worms from maturing and 

 laying 200 eggs, each of which would have caused an apple to be wormy. 

 Consider the apples each worth two cents more when not affected with 

 the worms. What is ths value to man of this solitary wasp ? 



9. A toad ate ten cutworms each night and thus saved a like 

 number of tomato plants in my garden. What do you consider is a 

 fair value of a tomato plant in cost and labor after it is set in the 

 garden ? What is the value of this toad in three weeks ? 



References. U. S. Farmers' Bulletins 586 and 606, on Collection 

 .and Preservation of Material for Study of Agriculture. 

 2 



