60 
honey-locust, Althca, pecan, black walnut, mountain laurel, honey- 
suckle, mulberry, white spruce, sour cherry, sumach, smoke-bush, 
locust, raspberry and the blackberry, elder, sassafras, various species 
of Spircca, arbor-vit?e, VibiiniiDii, and grape. Popular species not in- 
fested by it are Ailanthns or tree of heaven, papaw, spice-bush, bar- 
berry, trumpet-vine, the hornbeams, cedar, bittersweet, buttonbush, 
Judas-tree, fringe-tree, pepperbush, leatherwood, gingko, Kentucky 
coffee-tree, witch-hazel, English ivy, hickories except the pecan, 
hydrangeas, yellow^ jasmine, butternut, juniper, larches, sweet gum, 
tulip-tree, matrimony-vine, wax myrtle, black gum, syringa, pine, 
sycamore, the oaks, the rhododendrons, bald cypress, trumpet- 
creeper, blueberry, hemlock, Jl^istaria, and prickly ash. The last 
list is especially important in Illinois, thruout which the San Jose 
scale is certain ultimately to become generally distributed, because 
it includes a large and varied list of ornamentals from which selec- 
tions may be made without the risk of loss or injury by this most 
destructive pest. 
The San Jose scale is conveyed to distant points mainly by 
the trade in nursery stock, and otherwise it spreads only by means 
of the minute crawling young. Its means of dispersal are so slight 
that it tends to concentrate upon any tree infested until the latter 
becomes completely covered by it, a fact wdiich, taken together with 
its numerous generations, its rapid rate of multiplication, and its 
freedom from parasites capable of overcoming it, make it the dan- 
gerous enemy which it has become. 
The San Jose scale can be destroyed by the winter use of one of 
the lime and sulphur mixtures, which may either be purchased ready- 
made in condition for use by dilution only, or may be brought into 
solution bv boiling the raw materials together according to the fol- 
lowing directions. 
Materials: 15 pounds of lime, 15 pounds of sulphur, and 50 gallons of 
fairly soft water. For 50 gallons of the spray, heat 12 gallons of water in a 
40-gallon iron kettle, mixing, in the meantime, in a separate vessel, 15 pounds 
of sulphur w^ith enough water to form a thin paste. Add this sulphur to the 
water in the kettle and bring the mixture to a temperature just below boiling. 
Then add 15 pounds of best lump lime, keeping cold water at hand to use as 
the mixture threatens to boil over. After the lime is fully slaked, boil for 
40 minutes, with almost constant stirring. Then strain into a 50-gallon spray- 
tank and fill v;ith water, which had better be warm, although cold water will 
do. To prepare 100 gallons of the spray at a time, heat 20 gallons of water 
in the 40-gallon kettle, add 30 pounds of sulphur — previously reduced to a thin 
paste with water — and to this put 30 pounds of lime. Boil as before, and 
dilute to 100 gallons. 
If a supply of steam is available for cooking the mixture, this will be 
found a much more convenient source of heat. The cooking is then done in 
barrels or other vessels, from which the fluid is strained into the spray-tank. 
The disturbance caused by the introduction of steam makes stirring unneces- 
sary. When cooked with steam the mixture does not ordinarily become so 
dark as when boiled over a fire, but the insecticide efifect is nevertheless the 
same. 
