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ments conducted in that State with pure kerosene on bearing trees, 

 the tree had either been killed or injured, or the fruit buds had been 

 destroyed. He cited an instance where 132 nine-year-old Buffuni pear 

 trees bad been sprayed during the middle of January, 1898, with pure 

 kerosene in the hands of an expert, and that the entire block had 

 either been killed outright or injured to such an extent that they have 

 since been dug up and burned. He presented a photograph which was 

 taken May 24, 1898, of one of these trees. It was as free from foliage 

 as a tree in midwinter. Other photographs were presented showing 

 trees which had been seriously injured by the use of pure kerosene, 

 and which had beeu cut back to the trunks. In striking contrast with 

 these, still another photograph was presented showing one of these 

 trees, which had been sprayed with whale-oil soap at the rate of 2 

 pounds per gallon of water, in full foliage and heavily set with fruit. 

 Mr. Johnson also stated that still another block of thirty year-old 

 Duchess pear trees had been sprayed at the same time and under the 

 same conditions, none of which were killed, but at the same time all 

 the fruit buds were destroyed, and the development of the foliage 

 greatly retarded in the spring. Other trees in the same block which 

 were not sprayed with kerosene contained a full crop, and it was a 

 very easy matter to ascertain at a glance the very tree where the kero- 

 sene spray had been exhausted. In every instance, bearing trees, 

 whether sprayed the "middle of a September sunshiny day," in mid- 

 winter, or spring, from 50 to 100 per cent of the fruit buds had been 

 killed, and the vitality of the tree more or less affected, if not killed 

 altogether. Where pure kerosene had been used upon peach and 

 young plum trees, and in all cases with pear and apple, the growth 

 had been considerably retarded, the peach having been so seriously 

 injured it was necessary to cut back all the branches to the main 

 trunk. The peach and pear were so seriously injured that they made 

 but a very feeble growth during this season and stand in striking con- 

 trast with other trees by their side which were sprayed at the same 

 time with whale-oil soap at the rate of 2 pounds to a gallon of water. 

 Summing up the results of his experiments in Maryland, Mr. Johnson 

 stated that it seemed certain (1) that pure kerosene can not be safely rec- 

 ommended in Maryland as a spray for young and bearing orchard trees 

 at any time of the year; (2) that very old trees of certain varieties, such 

 as the Duchess pear, resisted the destructive effects of pure kerosene 

 more than other bearing trees, such as Buffum, a condition no doubt due 

 to the fact that the wood of the very old varieties is harder and more 

 matured, thus resisting the penetrating properties of the kerosene; 

 (3) that from 80 to 100 per cent of the fruit buds are killed on the bear- 

 ing trees, whether sprayed in the fall, midwinter, or spring; (4) that 

 young trees, especially peach and plum, are seriously injured or killed : 

 (5) that pure kerosene emulsion or kerosene diluted can not be safely 

 recommended until further experiments are conducted. He further 



