2 
known, however, as the peach-tree pest for nearly one hundred years. 
Its food plant prior to the introduction of the peach by Europeans 
was undoubtedly some of the wild cherries or plums of the Northeast- 
ern States. In other words, it is an Eastern species, and has followed 
the cultivated peach into the Middle and Western States. On the Pa- 
cific coast there is a closely allied species (S. opalescens) which 
takes its place as the important enemy of stone fruits. The Eastern 
species early attacked the cultivated peach and other stone fruits in 
New York and New Jersey. It is now widely distributed and is a 
common and perhaps the most important pest of these fruits in all the 
regions where they are grown east of the Rocky Mountains. A1- 
though it has been carried to the Pacific coast on nursery stock a good 
many times and obtained temporary foothold there, it does not seem 
to have ever permanently established itself in that region. The 
Pacific coast species named above is often confused with the Hastern 
species, but the two are quite distinct, although the habits and means 
of control are substantially the same for both species. This circular 
deals, however, with the more important Eastern species. 
NATURAL HISTORY AND HABITS. 
There is but one generation of larve annually. The moths appear 
as early as May in the latitude of Washington, D. C., and southward, 
over what approximates the lower austral region. In the upper aus- 
tral region, roughly comprising the States above the cotton belt and 
below the northern tier, the moths do not appear until after the mid- 
dle of June. In the transition region, which comprises the northern 
tier of States, together with most of New York and New England, 
the moths appear chiefly in July and later, emerging, however, as 
early as June, and belated individuals as late as October. June and 
July are therefore the months when the moths are the most numerous 
over the principal peach districts. 
The egg is deposited on the bark, usually at or near the surface of 
the ground, although rarely it may be placed well up on the trunk or 
in the crotches of the larger branches. The egg is very minute, not 
exceeding 0.2 mm. in length, oval, yellowish brown in color, and 
irregularly ornamented with hexagonal sculpturing. The young 
larva on hatching is very active, and immediately burrows into the 
bark, usually entering at a crack. Having worked its way to the sap- 
wood, usually near or below the surface of the ground, it feeds stead- 
ily during the balance of the summer and well into the fall, con- 
stantly enlarging its excavation, and causing the exudation of the 
gum intermixed with excrement and fragments of bark, which is so 
characteristic of its presence. It remains dormant in the larval state 
during winter and resumes feeding again the following spring, reach- 
[Cir. 54] 
