SCIENCE'S WARFARE OX FRUIT TREE FEST3 227 



three feet of the crown of the tree and within one foot of the surface. 

 It should also be remembered that the same substances that will kill 

 lice above ground will also kill them below ground if they can 

 only be put in contact with the lice, and then the orchardist should be 

 cautious not to accumulate in the soil about the crowns of his trees 

 substances that are likely either presently or after years of repetition, 

 to do his trees an injury. 



Conclusions As To Best Treatment 



Just before the buds open in the spring, spray very thoroughly with 

 a 7 per cent kerosene emulsion, a one to sixty Black Leaf dip (or some 

 other strong tobacco decoction), or a good whale-oil soap, one pound to 

 six gallons of water. Spray the entire trunk and also the ground about 

 the crown of the tree at the same time. Immediately after treatment 

 apply a Tanglefoot band over cotton so as to prevept the upward mi- 

 gration. If the lice become very numerous at any time upon the tops, 

 spray them forcefully with the 7 per cent emulsion, or Black Leaf, one 

 part in seventy parts of water. 



Root treatments are temporary in their effects. When the roots 

 become very badly infested, treat as above described with 10 per cent 

 kerosene emulsion. Black Leaf dip (one to fifty), two to three gallons to 

 a tree, or if soil is quite open and porous, carbon bisulfide. 



Tbe Green Apple Apliis 



This is the common green louse curling the leaves of the apple tree 

 in Colorado. While primarily a leaf feeder this louse attacks the tender 

 tips on growing shoots, especially grafts and water spouts. This insect 

 ranks close to the woolly aphis in extent of injuries to the apple trees. It 

 also attacks the pear, the thorn and the quince quite freely. 



Life History 



This louse remains upon the apple, or closely allied trees, through- 

 out the year and does not go upon other trees or vegetables. The first 

 lice in the spring hatch from eggs that were deposited the previous fall 

 upon the twigs of the trees. These first lice hatch a few days before 

 the buds open and are ready to insert their sharp beaks into the first 

 tender green tissue of the opening buds. These lice are all females and 

 become fully grown in about two or three weeks, when they begin giving 

 birth to living young. From this time on the lice increase very rapidly 

 if they are not kept down by their natural enemies or the insecticides of 

 the orchardist. 



At first all the lice are wingless, but the 10th to the 15th of May 

 in the warmer portions of the state, and about two weeks later in the 

 cooler orchard sections, the winged lice begin to appear and to fly from 

 tree to tree and orchard to orchard with the prevailing winds. About 

 the first week in September little brown wingless males and green 

 wingless egg-laying females will appear, and a little later the females 



