146 INJURIOUS AND BENEFICIAL INSECTS OF CALIFORNIA. 



Nature of Work.— The leaves are attacked by the young, which 

 later settle upon the branches where they mature. Large amounts 

 of honey-deAv cause smutting of the fruit and foliage of the infested 

 plants. 



Distribution. — The cherry or calico scale appears to be limited to 

 the San Francisco Bay region, especially in Contra Costa and Ala- 

 meda counties. 



Food Plants. — Though this coccid has but recently been reported 

 in California, it has already been found attacking cherry, pear, prune, 

 Virginia creeper and English walnut. 



Control. — Control measures are the same as for the European fruit 

 Lecanium {Lecanium corni Bouche). 



Natural Enemies.— A few specimens of Corny s fusca were reared 

 from this scale. 



THE EUROPEAN FRUIT LECANIUM 



Lecanium corni Bouche 



(Eulecanium armeniacum Craw) 



(Figs. 125, 126) 



Description. — The matured females vary from amber to a dark 

 reddish-brown, are very convex and longer than wide, being about 

 | inch long. The eggs are very small, slightly oblong and pearly 

 white. The young are light yellow, turning reddish-brown as they 

 grow older. 



Life History. — The females become mature in April and May when 

 great quantities of eggs are laid (Fig. 126) and the young begin to 

 hatch. These settle upon the leaves and younger twigs, where they 

 remain during the summer. As the leaves begin to drop many of 

 the young scales move to the branches where they mature by the next 

 spring. During the winter they are in the half-grown stage. This 

 species is exceedingly prolific and the insects are often so thick as 

 to entirely cover all of the smaller twigs. Severe infestations occur 

 only periodically. There is but one quite even brood a year. 



Nature of Work.— The abundance of the scale during certain years 

 is often quite alarming, but seldom is it a pest for more than two 

 successive seasons. Large amounts of honey-dew are secreted, caus- 

 ing smutting of the fruit and foliage. The younger twigs are infested 

 during the winter. The scale is more easily located during April and 

 May when they become full-grown. 



Distribution. — This is a very common scale, occurring through the 

 entire State and especially abundant in the apricot and prune grow- 

 ing sections. 



Food Plants. — The following food plants are attacked: apple, apri- 

 cot, ash, basswood, blackberry, cherry, currant, elm, gooseberry, 

 greasewood, grape, mountain holly, osage orange, peach, pear, pecan, 

 plum, prune, quince and Spanish chestnut. 



Control. — Spraying with miseible oils or with distillate emulsion 

 when the trees are dormant, as early as possible, gives excellent 

 results. In rare eases it is advisable to spray before all the leaves 

 fall. 



