55 



tree. For example, it is more efficient on the comparatively smooth- 

 harked Newtown Pippin and Yellow Bellflower, the varieties grown 

 in northern California, and less so on the rougher-barked White 

 Winter Pearmain, which is the common variety in southern Califor- 

 nia. Mr. Frederick Maskew, a horticultural inspector of Los Angeles 

 County, has also noted, as he informed the speaker, that this wash, 

 where it is not thoroughly effective, is very apt to cause an increase in 

 the spotting of fruit, so much so that the fruit of sprayed trees is some- 

 times more spotted than of unsprayed trees similarly infested. This 

 seems to come from the fact that the young from the few females 

 escaping the treatment near or on the fruit spurs are driven by the 

 limy coating on the bark to the young fruit and settle there, whereas 

 under normal conditions they would remain on the bark. 



Mr. Fletcher stated that one of the great objections to these washes 

 was the fact that they required prolonged boiling, and asked if any 

 successful experiments had been carried out in order to reduce the 

 time recommended, especially regarding the use of caustic soda in pre- 

 paring the wash without boiling, after the plan suggested by the late 

 Professor Lowe, of Geneva, N. Y. 



Mr. Burgess stated that washes made with caustic soda had been 

 tried by Mr. Parrott, and that he reported that the results were of so 

 variable a character that he would not recommend them for general 

 use. He further remarked that it seemed inadvisable for the ento- 

 mologist to recommend any treatment for general use unless it had 

 proved entirely satisfactory when tried in an experimental way. He 

 doubted the advisability of reducing the length of time of boiling the 

 lime and sulphur wash until more tests had been made, as fruit grow- 

 ers are apt to fail to boil the material sufficiently, and if the proper 

 chemical action is not complete imperfect results will be obtained from 

 spraying. 



Mr. Felt replied that he believed if the wash were boiled vigorously 

 for thirty minutes the necessary chemical action would take place. 



Mr. Piper stated that in the State of Washington the wash was thor- 

 oughly boiled for one-half hour, and when prepared in large quantities 

 was diluted with cold water. 



Mr. Summers remarked that it would seem that the conditions under 

 which the mixture was kept must vary somewhat in the different 

 experiments. Chemical action will evidently go on so long as the 

 mixture is at the boiling point. As the addition of the water to the 

 lime brings it up to this point, it would seem that all that is necessary 

 is so to insulate the vessel in which the mixture is kept that it will 

 not lose heat rapidly, and then to leave it for a sufficient length of 

 time to complete the necessary chemical action between the lime and 

 the sulphur. 



Mr. Gillette remarked that he had not been called upon to use these 

 washes for the San Jose scale, but would like to ascertain if anyone 



