1897-] ENTOMOLOGICAL NEWS. 223 



as is the usual practice, the balance of the season, and next Spring there 

 will be just as many as before to be dealt with. 



The truth is that we have not taken these facts into proper considera- 

 tion, and have attempted the impossible, /. e. extermination by a single 

 treatment or at one single season. Now I will make the very radical 

 assertion that the San Jose scale is a very easy species to deal with and 

 that its practical extermination in an infested orchard is not particularly 

 difficult. I will admit, however, that the treatment to accomplish this 

 result is heroic and somewhat expensive, but if the trees are not worth 

 the labor and expense involved, they might as well be taken out alto- 

 gether, because the scales will sooner or later kill them and will at once 

 reduce the value of the fruit if they do not make it actually unsaleable. 



To accomplish the result above indicated will require treatment both 

 in Winter and Summer, because Winter treatment alone, whatever the 

 medium, will, I am convinced by experience, prove ineffective, and re- 

 peated Summer treatment alone might prove injurious to the trees. 



After January ist and ai any time before the trees become in the least 

 active spray with pure kerosene of the ordinary 150 test. Be thorough, 

 but not wasteful ; use enough to make a film of kerosene capable of 

 penetrating into the smallest crevices, but let that film be of the thinnest 

 possible description. Do the work on a dry bright day with enough air 

 stirring to favor rapid evaporation and do it yourself, or at least super- 

 intend so that carelessness in the application be not charged against the 

 insecticide as inefficiency. 



Whale oil soap, two pounds in one gallon of water, will do almost as 

 well on smooth barked young trees, but not on rough or scaly barked 

 older ones, because of its much smaller penetrating power. Ten days or 

 two weeks thereafter trim out the trees thoroughly and carefully, cut out 

 all the wood not absolutely needed, but do not risk spoiling or even in- 

 juring the trees. Leave enough to carry a moderate crop of fruit if the 

 trees are in bearing. Do not trim before spraying to avoid cut surfaces 

 into which the kerosene might penetrate. The trimming is to remove 

 that wood least easily reached by the spray and thus to reduce to the 

 lowest possible point the chance of surviving scales. A few will survive 

 almost certainly. A few trees will probably be entirely cleared, but most 

 of them will harbor a few survivors no matter how many treatments are 

 made. Watch closely during the following July, lor traces of the scales 

 on fruit, and as soon as such are noticed spray again with undiluted kero- 

 sene. If applied as above directed so as to afford a chance for rapid 

 evaporation no harm will be done to fruit or trees, while in nine out of 

 ten cases the scales will be completely destroyed. Thereafter a close 

 watch each Summer and a prompt use of kerosene when scales are 

 noticed will not only prevent injury, but will in not too great a time " ex- 

 terminate" the scale. Try it ! don't rely upon laws and conventions to 

 do the impossible. 



