36 



ingly bad condition on account of the abundance of the San Jose scale 

 and a number were badly infested by the round-headed apple-tree 

 borer. 



A 20-per-cent mechanical emulsion of a light, crude petroleum (41.1° 

 Beaum^), obtained from the Derrick Oil Company, was applied to 32 

 apple trees and to 14 plum, pear, and quince trees. Examinations 

 this spring, even as late as June 12, showed that the apple trees had 

 apparently suffered little or no injury from the insecticide. These 

 trees are not in good condition this spring, but this is due almost 

 entirely to serious injuries inflicted by the two insects above named. 

 The Clapp's Favorite pear trees were injured somewhat, several limbs 

 being killed, the bark cracking in places and some suckers being thrown 

 out. The Dutchess pear trees suffered less and the Bartlett's appar- 

 ently escaped without any injury, being in excellent condition and two 

 of them bearing considerable fruit. The tips of a number of limbs 

 on a Globe peach tree were all dead this spring, but this can not be 

 attributed to the insecticide, as some untreated trees suffered in the 

 same manner. The treatment may, however, have facilitated winter 

 killing. Several Meeche's Prolific quince trees were also sprayed, 

 without the slightest deleterious effects being observed. 



Good's potash whale-oil soap No. 3, two pounds to the gallon, was 

 applied on the same day to 23 apple trees and 10 pear, plum, cherry, 

 and quince trees. The Clapp's Favorites, .Bartlett's, Beurre d'Anjou, 

 and Vermont Beauty pear trees suffered no injury and bear some fruit. 

 A yellow gage plum has no fruit and a Magnum Bonum plum bears 

 considerable. Both trees are in excellent condition and evidently suf- 

 fered very little or no harm from the insecticide, unless the fruit buds 

 of the first-named variety were killed, which is hardly probable. 



Good's tobacco whale-oil soap No. 6, two pounds to the gallon, was 

 also tested under the same conditions on 10 apple trees and 18 green 

 gage plum trees. The apple trees showed very little or no injury, 

 while most of the plum trees have suffered harm, which is shown by 

 the majority developing a considerable number of adventitious shoots. 



Two small apple trees were painted with linseed oil, the raw product 

 being used on one and the boiled on the other. The first was killed 

 outright by the application and the second nearly so. This substance 

 is so dangerous that its use in the fall can not be recommended. 



All of these applications have, so far as present examinations can 

 determine, given most excellent results so far as insecticidal purposes 

 are concerned. Many of the trees were veiy badly encrusted with the 

 San Jose scale and apparently not a single scale has survived the treat- 

 ment. This statement may need modification as the breeding season 

 advances, but the present indications are very satisfactory indeed. 



