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burned, and fifty-nine out of a total of one hundred and six wore gener- 

 ally infested with the scale. The orchard being somewhat isolated, and 

 the owner unwilling to bum all the trees, the whale-oil soap treatment 

 was recommended, and was applied a few days later. A careful exami- 

 nation of the orchard Aug. 27, 1897, showed only about half a dozen 

 living scales. Another examination on June 11, 1898, showed many 

 scales on last year's growth, although nearly all of those examined were 

 dead, a result of another treatment with the soap solution during the 

 past spring. The trees are thrifty and are making good growth, yet it 

 is evident that the scale is still present, and that remedial treatment 

 must be kept up for some time. 



In the spring of 1897 the writer personally treated a block of young 

 infested pear trees with whale-oil soap and water at the rate of two 

 pounds to one gallon. June 7, 1897, no scales could be found on the 

 trees, which during the fall of 1x97 were dug and -'heeled in." prepara- 

 tory to shipment. An examination of these trees Dec. 13, 1897, showed 

 them to be generally infested with the scale." In this case, sources of 

 infestation were found later near by, yet other stock growing between 

 the pears and the infested spots was apparently free from the scale I 

 am forced to conclude that a few scales survived the treatment, and by 

 fall their progeny had multiplied sufficiently to reinfest the trees. 



At Auburndale, Mass., a number of badly infested currant bushes 

 were thorougly drenched with the soap solution on Oct. 9, 1897. At 

 that time the bushes appeared to be nearly dead. When last examined, 

 June 11, 1898, they had made a vigorous growth and were in a remark- 

 ably thrifty condition. At the same time a few living scales and a few 

 young larvaj were found, showing that the treatment, while reducing 

 the numbers of the scale to a minimum, had not entirely exterminated 

 the insect 



A proper interpretation of the above-described experiences is that in 

 whale-oil soap applied as directed we have a valuable means for check- 

 ing the increase of the scale, and b}^ its use infested trees may be re- 

 stored to a thrifty condition. This remedy cannot be depended upon to 

 exterminate the insect ; and, in view of the cost of annual treatments, 

 the question to be considered is. Will it not be cheaper in the end to 

 burn the infested stock and start anew with trees free from the scale ? 



3. Kerosene. — Rect-ntly, through the eiforts of Professor Webster 

 and Dr J. B Smith, the value of pure kerosene as a remedy for this 

 insect has been extensively tested. The results thus far obtained, Avhile 

 uneven, have been on the whole satisfactory, and Dr Smith has even 

 advised owners of infested trees to use kerosene in preference to other 

 remedies He advises that during the month of September the oil be 

 applied as a very fine spray, and that only an amount sufficient to 

 moisten the surface be used. The trees must be perfectly dry. and the 

 time for treatment the middle of a warm, sunny day. VV hen used as above 

 directed, kerosene has been found to kill all of the scales, usually with- 

 out injury to the trees except in the case of the peach and plum. In 

 some cases, however, other species of trees have been destroyed, and at 

 the present writing farmers are not advised to make a general use of 

 this remedy until they have first tested it experimentally. 



4. Fumigation. — This method is particularly valuable to the nursery- 

 man. The trees to be treated are loosely packed in a tight room, and 

 exposed to the fumes of hydrocyanic acid gas for a period of forty-five 

 to sixty minutes. This gas is liberated by the action of acid on cyanide 

 of potash in water. The necessary quantities of the ingredients for one 

 hundred and fifty cubic feet of space are : cyanide potash (ninety-eight per 

 cent.), one ounce; sulphuric acid, one ounce; water, three ounces. The 

 cubic contents of the fumigation house are computed, and the nec- 

 essary amounts of chemicals prepared. The water and cyanide are 

 placed in a suitable earthen dish such as a bean-crock or other wide- 



