368 



apple no injury whatever was noted, even wbere applied at the rate of 

 2 pounds to the gallon, with the trees in full bloom. 



Behavior of different washes and iheir cost. — The diluted washes pre- 

 sented no ditticulties in apidication, ncn- 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 au 

 ordinary nozzle, as the liquid is too heavy for this purpose. Tlie strong- 

 est resin wash may be applied hot with an ordinary nozzle, but on 

 cooling the resin will separate out within au hour or two, hence the 

 necessity, at the greatest strengths used, of applying the liquid hot. 

 "VVhale oil soap Avashes, 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 Avith li 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 nuirked ai)pearance 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. 



Eesin wash at six times summer strength costs about G 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 preparatiou, Avhich is considerable. 



Kerosene 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 than 5 cents per gallon, and for the once diluted mixture, 2i 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. 



GENEKAL 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; aud 

 at this strength they also endanger the health of the plant. They do 

 not seem to aftect 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. 



