36 INSECTS AFFECTING VEGETATION 



Kerosene emulsion stock solution, 66 per cent oil, is made after 

 the following formula: 



Kerosene (coal oil, lamp oil) 2 gallons. 



Whale-oil or laundry soap (or 1 quart soft soap). 1 /^ pound. 



Water 1 gallon. 



The soap should first be dissolved in boiling water; then re- 

 move vessel from the fire. Immediately add the kerosene, and thor- 

 oughly agitate the mixture until a creamy solution results. The 

 stock emulsion may be more conveniently made by pouring the mix- 

 ture into the tank of a spray pump, and pumping the liquid through 

 the nozzle back into the tank for some minutes. The stock solution, 

 if well made, will keep for some months, and is to be diluted before 

 using. In order to make a 10 per cent spray (the strength for trees 

 in foliage) add to each 1 gallon of the stock solution about 5 2/3 

 gallons of water. (U. S. Dep. Agr. B. E. Cir. 12; B. 64 Del. E. S.; 

 Tenn. E. S. Vol. X.) 



The Scurfy Scale. The female scales are somewhat irregu- 

 larly oval or pear-shaped in outline, whitish in color and measure 

 about % of an inch in length. These scales may occur singly or 

 in considerable numbers, forming irregular patches in which case 

 the shape of the individual scales is not readily made out. It is from 

 these scurf-like patches that the insect derives its popular name. Like 

 the oyster-shell bark-louse the winter is passed in the egg stage. 

 The scurfy scale, while infesting a considerable number of plants, 

 is a less general feeder than is the preceding species. It occurs prin- 

 cipally upon rosaceous plants, such as the apple, peach, pear, plum, 

 cherry, etc., and also on currant and gooseberry among cultivated 

 plants, but seldom becomes so abundant as to cause particular in- 

 jury or to require specific treatment. Inasmuch as the life-history 

 of this species is quite similar to that of the oyster-shell bark-louse 

 the treatment for the latter species is equally applicable to this. The 

 point to be remembered is to keep a close watch to see when the 

 young begin to appear and then to spray within a few days, before 

 they have had time to form scales which would protect them. (Bui. 

 64 Del. Exp. Sta.; Cir. 121 B. of E. U. S. Dept, Agr.) 



The Codling Moth. This is the parent of the worm which 

 causes the wormy apple. The average adult has an expanse of wing 

 of about three-quarters of an inch. The general color of the front 

 wings is dark gray and of the hind wings light brown. Out near 

 the tip of each front wing, as the photograph shows, there is a well 

 marked brown patch which shows golden when the light falls on it. 

 The fact that the moth closely resembles the bark of the tree in its 

 coloring and being nocturnal in its habits, is ; no doubt, why so few 

 fruit-growers become familiar with the adult insect. The moth itself 

 is harmless to the fruit. 



It passes the winter as a larva (worm) in a cocoon in any good 

 hiding place, such as under the loose bark on trees. These larvae 

 begin to transform into pupae, and soon after the apple blossoms have 

 fallen the moths begin to emerge. The eggs laid by these are placed 

 chiefly on the leaves, and require on an average 9 or 10 days to 



