CHAPTEK VI. 

 PREVENTIVE AND COMBATIVE MEASURES. 



§ 12. Measures are known for the prevention and cure of many 

 fungoid diseases of plants of agricultural, sylvicultural or horti- 

 cultural interest. These have been deduced from the biology of 

 the parasite and its relation to its host, and have been used 

 practically with more or less success. In a large number of 

 cases, however, little advice can be given, because as yet the 

 cause of many diseases is obscure, while for others suitable 

 reagents for cure have not been found. Many of the methods 

 known are impracticable from the cost entailed in carrying 

 them out. Others, directed against some widespread disease, 

 fail from lack of organized co-operation, the efibrts of a few 

 individual cultivators here and there making but little headway 

 against the disease, so long as the patches of crop under treat- 

 ment are subject to fresh invasion from untreated places. It is 

 desirable on this account that the combating of diseases of our 

 cultivated plants should be conducted under some kind of state 

 supervision. 



The first step towards combating the more destructive diseases 

 of plants is the spread of knowledge concerning them, and the 

 remedies available against them. In Bavaria and other Gernian 

 states this is done for the diseases of sylvicultural importance by 

 regular courses of instruction in plant-pathology in the forestry 

 schools. In the same way it would also be advisable to give 

 similar instruction in agricultural schools, and also to make it a 

 subject for examination. Another important step consists in the 

 establishment of experimental stations where investigations in 



