VII.] 



* FINGER-AND-TOE » 



209 



and forming spores which may remain dormant in the 

 soil for some time, certainly for two or three years. It 

 has long been known that the best remedy against finger- 

 and-toe consists in the application of lime; and as far 

 back as 1859, Voelcker showed that soils on which this 

 disease is prevalent are deficient in lime ; and in many 

 cases in potash also. Later researches have only served 

 to emphasise the fact that the disease is associated with 

 soils of an acid reaction, in which calcium carbonate is 

 wanting, or present in very small proportions. The 

 fungus, as is generally the case with fungi, refuses to 

 grow in a neutral or slightly alkaline medium, and the 

 only way to get rid of the infection in the land is to 

 restore its neutrality by repeated dressings of lime. At 

 the same time, the land should be rested as long as 

 possible from cruciferous crops ; uneaten fragments of 

 diseased turnips, etc., should not be allowed to go into 

 the dung, or if they do, the dung should be used on 

 the grass land. Manures, again, which remove calcium 

 carbonate from the soil, like sulphate of ammonia, or 

 acid manures like superphosphate, should not be em- 

 ployed ; neutral or basic phosphates, with sulphate of 

 potash on sandy soils, should be employed instead. 



The following figures show the amount of lime dis- 

 solved by hydrochloric acid from soils affected with 

 " finger-and-toe," as compared with spots in the same 

 field where the disease was not in evidence : — 



o 



