SOME GENERAL PRINCIPLES 45 



Clover Sickness. — On certain of the soils of 

 Great Britain and probably on those of other coun- 

 tries in Europe, where clover has been grown quite 

 frequently and for a long period, as good crops can- 

 not be grown as previously, and in some instances 

 the crop is virtually a failure. The plants will start 

 from seed in the early spring and grow with suffi- 

 cient vigor for a time, after which they will show 

 signs of wilting and finally they die. Various theo- 

 ries were advanced for a time as to the cause before 

 it was ascertained by experiment what produced 

 these results. Some thought they arose from lack of 

 water in the soil, others claimed that they were due 

 to the presence of parasites, which in some way 

 preyed upon the roots, others again attributed them 

 to improper soil conditions. It is now just about cer- 

 tain that they arose from a deficiency of soluble 

 potash in the subsoil. Such, at least, was the conclu- 

 sion reached by Kutzleb as the result of experiments 

 conducted with a view to ascertain the cause of clo- 

 ver wilt. 



The cause being known, the remedy is not diffi- 

 cult. It is to grow clover less frequently on such 

 soils. Sufficient time must be given to enable more 

 of the inert potash in the subsoil to become available. 

 Another way would be to apply potash somewhat 

 freely to these soils, and subsoil them where this 

 may be necessary. 



It is thought that clover sickness is as yet un- 

 known in the United States and Canada, although 

 its presence had sometimes been suspected in some 

 sections where clover has been much grown. This 



