DISEASES AND PESTS OP PLANTS. 



47 



against the under-side of the leaves. If left until the leaves are curled, spraying 

 cannot be accomplished effectively. 



The following formulae are recommended : 



(a.) Lime-sulphur, 1 part to 9 parts of water, plus 1 part nicotine sulphate 

 40 per cent, to each 1,000 parts of diluted lime-sulphur spray. This formula must 

 be applied just before the buds open. 



If the trees are not sprayed before they are in leaf, or, if so, where another 

 application is deemed necessary, one of the following formulae may be used : 



(1.) Nicotine sulphate 40 per cent., 1 part to 1,000 parts of water, plus 5 Ib. of 

 whale-oil soap to each 100 gallons of the dilute solution. 



(2.) Lime-sulphur (30 Baume), 1 part to 30 parts of water, plus 1 part 

 nicotine sulphate to each 1,000 parts of the dilute lime-sulphur spray. 



Important. Do not use soap with lime-sulphur solution. Thoroughness of 

 application and attention to detail are essential. 



Pig 14. Result of a severe Infestation of woolly aphis on an 

 apple-tree. Note the excrescences on the twigs. (Photo, Mr. 

 Tom Wilson.) 



