1899] CAUSTIC ALKALI SOLUTION. 141 



their shelters by adhering to the " Felt" (as of soft-soap, for instance) 

 would be useless. 



I should, however, think that, unless under very special circum- 

 stances of thickness of bark, or under very careful superintendence, the 

 emulsion of soft-soap and paraffin was safer than that of paraffin 

 undiluted. 



For account of Cnjptococcus far/i, with reference to writings of 

 Continental and English specialists, see my Twenty-first Annual 

 Keport, pp. 6-10. 



CAUSTIC ALKALI SOLUTION. 



Winter Spraying Application for Bark of Fruit-trees. 



On April 8th of the past season I was favoured by Mr. A. Ward, 

 Head Gardener to the Lady Emily Foley (The Gardens, Stoke Edith 

 Park, Hereford), with the following recipe for a caustic alkali solution, 

 which he mentioned as being found by fruit-growers to be of great 

 service in ridding fruit-trees of many of their insect foes. I am not 

 personally acquainted with the action of the application, but, the 

 recommendation coming from such a known horticulturist, I have no 

 doubt that it is serviceable, and, if used according to Mr. Ward's 

 directions, safe. Still, as operators are not always careful what they 

 are about, a suggestion of care as to such a powerful solution possibly 

 doing injury if settling on young shoots may not be out of place, and 

 I have also italicised Mr. Ward's direction that the water should be 

 boiling tvhen used in mixing the ingredients, as this is an important 

 point. Mr. Ward's communication is as follows : — 



" The principal ingredients are crude potash (pearlash) and caustic 

 (commercial) soda, and these chemicals should be of the best quality 

 obtainable. The way to make the wash is as follows : take one pound of 

 caustic soda and one povind of caustic potash, and place in separate 

 buckets or tubs, and pour on sufficient huiling water to dissolve them. 

 Then add the two solutions together and dilute with sufficient hot 

 water to make ten gallons, when it is ready for use. This may be 

 applied to Apple, Pear, Plum, and Cherry trees, also Gooseberry and 

 Currant bushes. For Apricots, Peaches, and Nectarines a weaker 

 solution, or one pound each of the chemicals to twelve and a half gallons 

 of water had better be used, although I have used it full strength on 

 these without harm resulting. 



"The best time to apply it is when the trees are in a dormant state. 

 All insects, together with their eggs, larvae, chrysalids, scale (whether 

 brown or the mussel species), and any aphides which may be hibernating 

 in the rough bark of the trees, are killed off by its action, also lichen 



