New York Agricultural Experiment Station. G13 



quite evident tliat a whale-oil soap solution made by dissolving two 

 pounds of tlie soap in a gallon of water, will kill all the " Pernicious 

 Scale " insects, if thoroughly applied, and not injure the trees. 

 Hence, failure by the process of dipping must be the result of care- 

 less work. 



(h) Other Scale Insects. 



As soon as there was the least evidence of the eggs of the Oyster- 

 shell Bark-louse hatching, a number of poplar trees in nursery of 

 Keene & Foulk were washed with the following substances : Lin- 

 seed oil, whale-oil soap, 2 pounds to 1 gallon of water ; and 

 kei-osene emulsion 1 part to 4 parts of water. These washes 

 were applied each to an equal number of the trees May 28th. 



Examination of the trees July 8th showed the following results : 

 Yery few live specimens on trees treated with linseed oil ; about 

 twice as many alive on trees washed with whale-oil soap ; while 

 on trees treated with kerosene emulsion they were so numerous no 

 estimate could be made. Portions of the bark on these trees were 

 rough ; this would account for the escape of a few of the pests where 

 only one application was made. No injury resulted to any of these 

 trees. 



A number of poplar trees which had not been previously treated 

 and on which the young were issuing from beneath the old scales, 

 were sprayed June 6th with crude petroleum emulsion diluted with 

 20 parts water. A number of other trees were sprayed the same 

 day with crude carbolic acid (95 per cent.), 1 part to 100 parts 

 water. 



June Tth, dead specimens were found on all the trees sprayed June 

 6th, but the young were still issuing from beneath the old scales in 

 countless numbers ; hence no estimate of the number killed of those 

 treated could be made. After this last test Keene & Foulk had 

 all their poplar trees washed with the strong whale-oil soap solution. 

 Only the bark lice not reached with the wash escaped. 



The value of a series of applications of crude petroleum and kero- 

 sene emulsions was tested on Euonymus latifolius and Enonyinus 

 europCEUs against the "Enonymus Scale" {Chianaspis euonynii) in 

 nursery of Parsons & Sons, of Flushing. Both emulsions were 

 diluted with ten parts water and applied on the following dates : 

 Crude petroleum emulsion, 1 to 10, 20 plants, June 21st, July 1st 



