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do notice it, fail to recognize it as black scale. In five months it 

 is about as large as the adult in diameter, but quite flat, a dull blue 

 in color, and from this time on it is quite difficult to kill with the 

 best of fumigation, until when full of eggs it becomes almost im- 

 possible to kill it by a dose the tree will stand, the shell being very 

 hard and impervious to gas or spray. It is sealed so tight to the 

 tree that no gass can penetrate it. 



When the mother deposits her eggs, her body arches over them, 

 decreasing in size as the number of eggs increase, until when the 

 eggs are all deposited to the number of 750 or more, the insect 

 soon dies, and in about four or five months the hatching begins. 



There is one efficient parasite of this scale, a small black fly, 

 Scutellista cyanea, often called "Scutes," which deposits one or more 

 eggs under the scale. These hatch before the scale eggs do, and 

 the resulting larvae lives and grows on an egg diet, often consum- 

 ing all the eggs before it pupates. After going through the pupa 

 stage, the mature fly pierces the top of the scale shell and crawls 

 out. The old scale shells showing holes in the top are only empty 

 houses where the parasites have done their work and gone. This 

 largely occurs before the fumigation season begins, and the remain- 

 ing larva still in the shells are seldom killed by the gas as I have 

 myself observed. The objection to fumigation, that the parasite 

 is killed as well as the scale is therefore unfounded as to the larva. 



The list of plants and trees harboring Black Scale is very long, 

 the more common ones include the citrus trees, the pepper, olive, 

 oleander and apricot, and the wild night shade weed, which last 

 should never be allowed to grow in or near orchards as an added 

 breeder of the Black Scale. 



The black smut on the leaves of trees infested with this pest 

 is caused by a black fungus which grows in the honey dew, an 

 excretion thrown out by the scale and greatly relished by the ants 

 who always come after it, but who, instead of injuring the scale, 

 probably help to spread it. 



Fumigation beginning at the completion of the hatch and con- 

 tinued to the blue stage is the only reliable remedy for Black Scale, 

 though when they are all very young, the kerosene or distillate 

 emulsion sprayed as strong as the tree will bear, will check them. 

 But owing to the thick foliage of citrus trees, some scale always 

 escape the spray, soon to make the trees as bad as ever. On decid- 

 uous trees, after the leaves fall, carrying many scale with them, 

 spraying results are much more satisfactory. 



