478 Important Orchard Pests and Spray Formulae. 



covering, circular in form. Slightly infested bark shows, in 

 winter and spring, minute dark cones about the size of pin heads, 

 often accompanied by a reddish discoloration of the surrounding 

 bark. When the bark is crowded with insects many dead ones of 

 light color give an ashy appearance and the inner bark may show 

 much discoloration. In June young come forth and crawl about, 

 but shortly insert their mouth parts and become fixed in their life 

 position. Several broods follow throughout the summer, the later 

 ones settling upon the fruit and causing much spotting. Treat- 

 ment is most successful while leaves are off and the temperature 

 is above freezing. Lime-sulphur, prepared at home or the com- 

 mercial product, is the standard remedy. Miscible oils are also 

 effective when thoroughly applied, as is whale oil soap at 2 

 pounds per gallon of water. 



Oyster Shell Baric Louse and Scurfy Scale. — These common 

 scale insects are larger and lighter than the San Jose scale. Both 

 winter as eggs beneath the scale covering and issue about June 

 10 to 15. While young, they may be killed by any of the common 

 strengths of contact sprays but, where lime-sulphur at winter 

 strength is being regularly used, enough material will adhere to 

 the bark to control the young of the above scales when they hatch. 



Aphides. — These plant lice are usually brought to notice 

 through the curled appearance of leaves on terminal shoots of 

 young apple, plum or cherry trees. The lice suck the interior leaf 

 juices and are killed by soap solutions, tobacco extracts, oil emul- 

 sions or other contact sprays applied at summer strength. Treat- 

 ment before the leaves curl is of advantage, since the insects can 

 then be more readily hit. 



Codling Moth. — Wormy apples are almost wholly due to the 

 larvae which hatch from the eggs of this moth. The eggs are laid 

 from 10 to 20 days after blossom time. On hatching, the minute 

 worms usually seek entrance to the apple at the blossom end 

 where they feed upon the fleshy stamens and in the calyx before 

 entering the apple. Any arsenical poison there will kill the in- 

 sect. Paris green and arsenate of lead have both proven effective. 

 Either may he combined with bordeaux when used for fungous 

 diseases, but only the arsenate of lead is adapted for combination 

 with the dilute lime-sulphur now used at summer strengths. (See 



