1 84 Lime-sulphur Wash for Use on Foliage, [june, 



calves; but where conditions are suitable it will be seen that 

 it affords a good margin of profit. 



A LIME-SULPHUR WASH FOR USE ON FOLIAGE. 

 E. S. Salmon, F.L.S. 



Mycologist to the South- Eastern Agricultural College, Wye, Kent. 



The object of this article is to direct the attention of 

 farmers and fruit-growers to the fact that a summer wash 

 for use against certain fungus diseases of plants can be 

 prepared by boiling lime and sulphur together, and that this 

 wash, unlike "flowers of sulphur " and the "liver of sulphur " 

 solution, is not readily washed off by rain. Some experiments 

 which have recently been carried out show that this lime- 

 sulphur wash is efficacious against "powdery mildew," and 

 the experience lately obtained in other countries indicates that 

 in certain cases the wash may be useful in combating attacks 

 of apple "scab " or "black spot." 



Experimental Work. — The experiments carried out in con- 

 nection with "powdery mildew" were briefly as follows. In 

 one set of experiments young hop-plants affected with the 

 well-known hop "mould" or mildew (Sphaerotheca Humuli) 

 were treated in the following manner. A considerable 

 number of leaves were chosen which bore patches of the 

 mildew in a powdery and actively growing condition ; each 

 leaf was then divided by a line down its midrib into two 

 halves. Each half of these selected leaves bore from one 

 to four patches of mildew. One half of each leaf was 

 painted over with the lime-sulphur wash, while the other 

 half — which served as a "control" or check — was either left 

 untreated or was painted over with pure water. In every case 

 the patches of mildew on the treated half of the leaf were 

 killed — the spawn (mycelium) of the mildew drying up, but 

 not changing colour ; on the other half of the leaf the mildew 

 continued to increase rapidly. Further, no fresh infection 

 took place on the treated half of any of the leaves, although 

 spores (conidia) must have constantly been blown there from 

 the powdery patches on the untreated part of the leaf. In 

 one series of experiments investigations were made with 



