SPRAYING FOR DISEASES 259 



10. If a Catalpa wood-lot contains 1,000 ten-year-old 

 trees per acre, and each tree would make two fence 

 posts, what would the trees on five acres be worth at 

 30c a post? 



Free Bulletins, U. S. Dept. of Agriculture 

 Farmers' Bulletins 



No. 54. Some Common Birds in Their Relation to Agricul- 

 ture. 



No. 150. Clearing New Land. 



No. 173. A Primer of Forestry. 



LESSON LXXIII 



SPRAYING FOR CODLING MOTH AND FUNGOUS 

 DISEASES 



Time to spray. It is late in April and the apple 

 blossoms have just fallen from the trees. We know now 

 that the codling moth larva or "apple worm" will soon 

 be eating its way into the blossom end of the apples, 

 and we know, too, that unless we do something to check 

 its ravages, our fruit will fall or be wormy and worth- 

 less. Fortunately we do not have to give up to the cod- 

 ling moth, for we may spray our trees, kill the moth, 

 and save the apples. 



Lime-sulphur and lead arsenate. If any farmer in 

 the neighborhood has a spray pump, he no doubt would 

 be willing to loan it to the school for this lesson. The 

 school should own some good spray pump, such as the 

 Gould's Pomona, and use it for demonstration purposes 

 in the orchards of the district. The spray material usu- 

 ally used is the combined lime-sulphur mixture and lead 

 arsenate. The lime-sulphur checks the spreads of such 



