The Lecanium Scales. 445 
free by application to the Agricultural Experiment Station at 
Berkeley. 
The Black Scale (Lecanium oleae)—This scale is almost a 
universal pest, especially in regions adjacent to the coast, though 
it has recently demonstrated its ability to endure interior valley 
conditions. It affects citrus fruit trees and some deciduous trees 
as well, and a fungus growing on its exudation causes the black 
smut, which renders tree and fruit unsightly; but this smut ac- 
companies other scale insects as well as this one. It is especially 
troublesome on the olive, and will quickly spread to ornamental 
plants and vines in the garden. It is a very difficult scale to 
subdue. On citrustrees the fumigation method is the only 
practical recourse. On deciduous fruits it requires both winter 
and summer spraying to hold it in check. In spite of the fact 
that immense numbers are killed by parasites, and perhaps by 
fungi as well, it is still a grievous pest, and should be fought 
unceasingly. 
Soft Orange Scale (Lecanium Hesperidum).—This scale is a 
pest of citrus trees the world over. The scale is ovoid, a little 
wider at one end than the other; length, from one-twelfth to 
one-seventh of an inch; color, dark brown on convex part, and 
a lighter brown surrounding margin; it has two indentations on 
each side, and one on posterior end. The engraving does not 
bring out these characters well, but shows the way in which the 
scale is seen on the leaf. It fortunately is usually held in check 
by natural agencies. 
Brown Apricot Scale—The apricot tree, though defying the 
most ruinous scales of some other trees, is beset by scales of the 
lecanium family. The black scale is one and the brown apricot 
Brown Apricot Scale of Deciduous Fruit Trees. 
. & 
scale another. It is Lecaniuin Armeniacum. This scale is boat- 
shaped; when reaching maturity, wrinkled; the color is a shiny 
brown, darker in the center, lighter at the edges. A full-sized 
