14 CALIFORNIA AGRICULTURAL EXTENSION SERVICE [CIRC 42 
rise to a second and to subsequent generations of caterpillars which 
infest fruit. By their feeding the late caterpillars sometimes destroy 
large amounts of marketable fruit (fig. 12). Where this pest is 
serious it may be controlled by spraying with liquid lime-sulfur, 9 
gallons to 100 gallons water, before the buds swell. Where Bordeaux 
mixture is preferred combine with arsenate of lead, 3 pounds to 100 
gallons of spray. Nicotine sulfate, 34 pint to 100 gallons of water, 
will also kill this insect if applied at the time the caterpillars are 
present on the surface. 
Leaf Eating Caterpillars.—There are various kinds of chewing 
insects which eat peach foliage, including cankerworms, red-humped 
caterpillars, tent caterpillars and leaf rollers. Different methods of 
control may be used, but in general, spraying with basic arsenate of 
lead, 3 pounds to 100 gallons of water, at the time the insects first 
appear will give good results. Pyrethrum or buhach powder, 2145 to 
5 pounds soaked over night in 5 gallons of water, and then enough 
water to make 200 gallons of spray, has been effective in the control 
of cankerworms. Pyrethrum is non-poisonous to humans and may, 
therefore, be used in preference to arsenate of lead when spraying the 
fruit near harvest time. 
Black Peach Aphis, Anuraphis persicae-niger Smith—This is a 
shiny black plant louse that appears in great numbers on tender shoots 
and fruit in the spring. They are easily controlled by spraying with 
1 pint of nicotine sulfate and 4 to 5 pounds of fish oil soap to 100 
gallons of water, or by dusting with nicodust, as soon as the insects 
appear. This insect also sometimes infests the roots and may be 
killed by the paradichlorobenzene treatment. 
Scale Insects.—Various scale insects such as San Jose scale (Aspid- 
totus perniciosus Comst.), the black scale (Saissetia oleae Bern.), the 
peach scale (Lecamium persicae Fab.), the brown apricot scale 
(Lecanium corni Bouché) and others may become serious pests on the 
peach. The lime-sulfur sprays which are applied for other pests will 
generally keep these insects under control. However, if they become 
severe, oil sprays applied in the winter months (December—January) 
may be necessary. 
Red Spiders.—There are two forms of red spider which may infest 
peach trees; namely, the brown mite (Bryobia praetiosa Koch) and the 
common red spider (Tetranychus telarius Linn.). The former hiber- 
nates in the egg stage on the trees, adults appear in early spring, and 
may become numerous during the summer. It is rarely troublesome 
but when it is serious one of the heavy oil sprays applied in the winter 
months will control this form. The common red spider, on the other