NEW YORK EXPERIMENT STATION BULLETIN 369 



hatch eai'lier Ihuu others. Last year many newly hatched lice were ob- 

 served on apple trees in the vicinity of the station as early as May 7. 



The newly hatched lice are very small, measuring only about 0.4 mm. 

 in length and half as broad. A good idea of their shape is given in Plate 

 n, tig. 1, c. Their bodies are nearly llat and light yellow in color. They 

 Avander about for a short time, varying from a few hours to a day or more, 

 finally settling down, most of them on the new growth, where they begin 

 to suck the sap by means of their sharp, thread-like mouth i^arts. They 

 probably never go to the leaves and only one or two cases have been 

 reported where the scales were found on the fruit. It is probable that 

 when once settled on the bark the females never move. 



The scales grow rapidly and by the latter part of July are mature. 

 Most of the scales grow to have the appearance already referred to and 

 shown at Plate I, fig. 1. These are the female scales and they are in a 

 very large majoiity. The male scales are much smaller and more regular 

 in outline. The posterior portion of the scale is also very different in 

 that it is hinged so as to allow the mature male to escape. 



In color, the male and female scales are similar, both finally becoming 

 an ash gray tint. The mature male is a delicate two-winged insect 

 very different in appearance from the female. A mature male is shown 

 in Plate II, fig. 1, a, and a mature female, with her scale removed, at e. 



The eggs are laid during the middle of the summer, the body of the 

 female growing smaller as each one is produced until finally there is little 

 left but a withered skin. The eggs remain under the scales all winter, 

 finally hatching in the spring as previously stated. 



Means of distribution. — As the scale passes the fall, winter, and part 

 of the spring in the egg state, the eggs being protected by the scales, it is 

 evident that the insect may be easily distributed by means of infested 

 stock. When the trees are not badly infested the scales are easily over- 

 looked, and thus as each scale protects thirty or forty eggs, a nursery 

 tree even slightly infested may finally harbor enough scales to do very 

 serious injury in the orchard. 



Kemedial measures. — Badly infested nursery trees should be dug up 

 and burned. Where especially choice trees or shrubs are infested they 

 may be. successfully treated either by applying a wash during the winter 

 or by spraying in the spring while the young lice are active. For a 

 winter wash either kerosene emulsion or whale oil soap may be used. 

 The kerosene emulsion should be diluted with three parts of water, and 

 the whale oil soap* used at a strength of one pound to two gallons of 

 water. 



Before applying the wash tlie infested parts should either be scraped 

 gently or rubbed with a stiff scrubbing brush to loosen the scales. This 

 allows the insecticide to reach the eggs which would otherwise be pro- 

 tected by the scales. For spring treatment, spray the trees as soon 

 as the young lice appear. Either kerosene emulsion or whale oil soap 

 solution may l^e used. The former should be diluted with seven parts of 

 water and the latter used at a strength of one pound to seven gallons of 

 water. 



Where practical the winter treatment is preferable, as many of the 



.*In buying whale oil soap much pains should be taken to get a good article. Much of the soap 

 on the market is very poor. The Leggett brand has proven of good quality, also that manufac- 

 tured by Jas. Good, Philadelphia, Pa. 



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