78 SHADE TREES. 



to penetrate into every crevice and irregularity of the bark. 

 This will kill the hibernating forms and prevent any start 

 next season. 



Incidentally, the forcible solid jet just recommended, may 

 be applied with a pump and small nozzle, and this has also 

 been used to dislodge the cottony maple scales (see page 73) 

 from twigs and branches early in the season before the eggs 

 have hatched. 



THE SCURFY SCALE. 

 Plate IV., Figs. 4, 4a, 4b. 



This scale infests the poplar most frequently, among the 

 shade trees, but is also found on maple and occasionally on 

 others. It is very pale gray, almost as broad as long, with 

 Attacks a yellowish point or head. Beneath this scale 



chiefly. the purple eggs are found during the winter, 



and in June they hatch into purplish crawling larvae which 

 have the same general habits of other scale insects, and like 

 them suek the plant juices. There is only a single brood 

 which matures in September, and is rarely abundant enough 

 to do any real injury. 



Remedial Measures. 



This scale is thinner than most others of the armored 

 forms, and may be reached by the lime-sulphur or other caus- 

 tic sprays in winter. The caustic corrodes the scaly cover- 

 if serious ^ n o? an( ^ tne e gg s wash out and are scattered 

 use caustic. anc ] destroyed on the ground. Even caustic 

 lye or soda at the rate of 1 pound in 1 gallon of water will 

 accomplish this. If no winter application is made it will be 

 necessary to wait until the eggs hatch in June, and then 

 apply whale-oil soap or kerosene emulsion as recommended 

 for the oyster-shell scale. 



