368 
apple do injury whatever was noted, even where applied at the rate of 
2 pounds to the gallon, with the trees in full bloom. 
Behavior of different washes and their cost. — The diluted washes pre- 
sented no difficulties in application, nor is there any trouble in applying 
the Oregon and California washes at twice the ordinary strength. 
Pure kerosene emulsion can not be very satisfactorily sprayed with an 
ordinary nozzle, as the liquid is too heavy for this purpose. The strong- 
est resin wash may be applied hot with an ordinary nozzle, but on 
cooling the resin will separate out within an hour or two, hence the 
necessity, at the greatest strengths used, of applying the liquid hot. 
Whale oil soap washes, even at 3 pounds to the gallon, are thin enough 
when cool to be sprayed without much difficulty, and no trouble what- 
ever was experienced with 1^ to 2 pounds to the gallon. Hard soap, 
used in this experiment, solidified almost immediately into a rather 
tenacious soft soap, even at 1 pound to the gallon, and in this or greater 
strengths can not be sprayed except at very high temperatures. When 
once on the tree, however, it adheres much better than fish-oil soaps, 
or at least the evidence of its presence on the tree is much more appar- 
ent, the whitening of the bark being noticeable months afterwards. 
Whale-oil soaps do not give this marked appearance to the tree, and 
even at the start the tree remains only somewhat darker, as though wet. 
The cost of the stronger applications are approximately as follows: 
Whale-oil soap, at 4 cents per pound, using 2 pounds to the gallon, 
gives an 8 cents per gallon wash. It was found impossible to make a 
soap by buying the ingredients any cheaper than it could be obtained 
from the soap manufacturers. 
Resin wash at six times summer strength costs about 6 cents per 
gallon by buying the ingredients in wholesale lots, viz, lye in drums 
of 800 pounds capacity, and the resin and oil by the several barrel lots. 
This does not include the expense of preparation, which is considerable. 
Keroseue at 6 cents per gallon for a cheap grade, with soap at 4 
cents per pound, would represent a cost for the pure emulsion of a little 
less thau 5 cents per gallon, and for the once diluted mixture, 2^ cents. 
The crystal potash lye was secured at retail and cost 15 cents a 
pound, making the strongest wash applied cost 30 cents a gallon. 
GENERAL CONCLUSIONS. 
1. The Oregon and California washes are practically valueless under 
the conditions obtaining in Maryland, even at twice the strength re- 
ported to be effective on the Pacific Slope. They are without action 
on the health or fruiting of the plant. 
2. Lye washes are, in the first place, too expensive for use at the 
excessive strength required to accomplish any valuable results; and 
at this strength they also endanger the health of the plant. They do 
not seem to affect the blooming. 
3. Pure kerosene applied to the entire plant kills the scales, but 
unfortunately also the plant, at least in the case of peach. 
