this Department, with a view to taking prompt measures to check so 

 far as possible any fungous disease which may threaten any crop 

 during the season. 



Any person in the state who may be troubled by any disease of 

 plants cultivated either for use or for ornament is strongly urged to 

 send to this Department specimens of the plants attacked, with notes, 

 as full as possible, on the appearance, effects, and spread of the 

 disease. Such notes often have considerable intrinsic value when 

 carefully made and accompanied by specimens showing the affection 

 to which they relate. The Department will give especial attention, 

 during the coming season, to communications relating to the treat- 

 ment and prevention of plant diseases and will reply promptly, with 

 detailed recommendations for each special case. It is hoped that the 

 responses to this call will be sufficient to show that it is appreciated, 

 and that inertia is not the controlling quality of Massachusetts 

 cultivators. 



A general account of the Fungi, especially of such ;ib cause diseases 

 of plants, will be found in th > Annual Report of this Station for 1889, 

 at pages 195-211. From the nature of parasitic fungi and the fact 

 that they are for the most part, paiasites within the tissues of their 

 hosts, it is evident that our efforts must be directed toward preventing 

 their attacks. The present state of our knowledge does not enable 

 us to stop the development of a parasite within its host-plant, with- 

 out injury to the host, after it has once obtained a foot-hold. 



Tlie various forms of preventive treatment for a given disease fall 

 naturally under two heads, field and orchard hygiene and individual 

 protection. The former includes the minimizing of all sources of 

 infection by the removal of rubbish, of remains of diseased plants or 

 fruits, or of wild plants which may serve as propagators of the 

 disease. The latter includes the application to the plants to be 

 protected of substances in liquid or solid form which shall fortify 

 them against the attacks of fungi which cause disease. Such 

 substances are known as Fungicides. Since different fungi 

 attack their hosts in very different ways, since their modes of 

 development and the effects which they produce differ widely, it is 

 plain that no all-embracing rule can be laid down for the treatment 

 of fungous diseases. Certain principles of general applicability can, 

 however, be stated, certain general diiections can be given, and 

 instructions regarding the preparation and application of those fun- 

 gicides which have been proved to be most useful and effective can be 



