602 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



Similar to it is the Oleander Scale * which, on account of its fre- 

 quent occurrence on lemons is sometimes called the lemon-peel 

 scale. The two latter forms are common in California, but not 

 known to infest citrus in Florida. The San Jose scale (see page 

 470) is a pest in both localities, but does not do as much damage to 

 the citrus fruits as it does to the deciduous kinds, being largely 

 over-shadowed by the other scales mentioned. 



In Florida the most destructive scale is the Florida Red Scale 

 or Round Scale f. It lacks importance from the fact that it is not 

 so widely distributed as some of the others and does not seem to 

 spread so rapidly or to be as generally present in an infested plant- 

 ing. This scale is reddish brown in color with a lighter brown 

 center and is nearly circular. It infests the leaves and fruit and 

 will easily defoliate a tree when it is abundant. 



The Chaff Scale J, a thin gray form, sometimes completely 

 covers the bark of trees in Florida, especially the bark of the 

 smaller branches. The Snow Scale, so called on account of the 

 white color of the males, is closely related to the scurfy scale of the 

 apple. Neither the Chaff Scale nor the Snow Scale is seriously 

 injurious. 



The Unarmored Scales 



Members of this group lack the separable scale found in the 

 previous group of scales, the protection to the body being provided 

 by a thickened and sometimes hardened body-wall rather than by 

 a secretion from the body wall. They are generally larger than the 

 armored scales and are much thicker bodied, their shape suggesting 

 that of the common terrapin, on which account several species 

 receive local names of terrapin-scale or tortoise-scale. 



The Black Scale If is the most important of the scale insects in 

 California, being, according to Quayle, the most destructive of the 

 insects attacking citrus fruits in that state. It occurs in Florida 

 but rarely attacks citrus plants there, being more common on 

 oleander and other trees. Its injury is due not so much to its feed- 

 ing habits as to the secretion by the scales of a substance resembling 



* A. hederae Comstock. 

 t Chrysomphalus aonidum L. 

 J Parlatoria pergandii Comstock. 

 \Chionaspis titri Comstock. 



^Saissetia olex Bern. See H. J. Quayle, Bulletin 223 California Agr. 

 Exp. Sta. 



