1036 THE FRUIT INDUSTRY IN NEW YORK STATE 



The causes for failures are not always- apparent, but spraying prac- 

 tices with many orchardists are usually faulty in that there is no 

 systematic treatment of the trees, and directions for spraying are 



not always correctly interpreted or care- 

 fully followed. For orchards annually 

 subject to attack the following meas- 

 ures are recommended: 



1. Practice clean culture so as to pre- 

 vent flies from wintering in accumu- 

 tions of matted leaves and weeds. 



2. Kemove rough bark in order to 

 discourage flies from wintering on the 

 trees and to render them more exposed 



to spraying mixtures. Bark is more 

 FIG. 316. THE PEAR 



PSYLLA: LARVA easily detached immediately following 



(enlarged) ft wet period> C are should be taken not 



to cut into the live tissues. 



3. Spray thoroughly to kill the flies with nicotine solution 

 (40 per cent) using three-fourths pint to one hundred gal- 

 lons of water and three pounds of soap, preferably during a warm 

 spell in November or December, or during March or early 

 April. Select a day when the mixture will not freeze on the trees. 

 Some growers prefer a miscible oil, using one gallon diluted with 

 fifteen gallons of water. This treatment should only be made in 

 spring before the buds open and on days when there is no danger 

 of freezing of the spraying mixture. 



4. Spray trees thoroughly with the lime-sulphur mixture at 

 winter strength so as to destroy the eggs. This treatment should 

 be made during the latter part of April or early in May, or just 

 before the cluster buds separate at the ends. 



5. Spray the trees thoroughly just after blossoms drop in order 

 to kill the newly-hatched nymphs, with nicotine solution (40 per 

 cent), using three-fourths of a pint to one hundred gallons of water 

 and three pounds of soap or kerosene emulsion diluted with 

 eight parts of water. Direct the spray into the axils of the leaves 

 and fruits, and wet both surfaces of the leaves. 



If the work is well done, it is not necessary to cany out all of 

 these measures each year. If the trees have been carefully scraped, 



