334 JOURNAL OF ECONOMIC ENTOMOLOGY |Vol. 14 



Table V - WHiTE\vi>sH Treatment, Busenbark Orchard 

 Roseburg. 1920 



A study of tables IV and V will show that in general there was a dis- 

 tinct reduction of infestation in the whitew^ashed trees, although in 

 some cases this is not much greater than may be accotuited for by chance 

 irregularity in distribution of infestation. 



The rows (A3) treated with the wash containing naphthalene show 

 up to best advantage. In the ten trees examined at Salem only two 

 trees were found to be infested, and these harbored a total of only three 

 larvae. The trees at Rosebtirg show up even better, and in the ten 

 trees examined no infestation w^as found. 



Fuller's Earth -Molasses Wash 



In the course of our w^ork a series of experiments was performed in 

 an effort to develop a wash which would be more suitable than white 

 wash as an application to the bases of the trees for root borer control. 

 After preparing some forty different mixtures, we succeeded in prepar- 

 ing a wash which seemed to fulfil most of the requirements quite well. 

 The wash is composed primarily of Fuller's Earth, molasses, and glue. 

 This forms a very hard coating w^hich is quite resistant to weather con- 

 ditions, and shows a minimum of cracking. 



The Fuller's Earth washes were applied in a series quite closely par- 

 allel with the whitewash series, as shown by the following formulas: 



"One larva found in trunk above area of whitewash was not included in this table. 



