22 BOARD OF AGRICULTURE. [Pub. Doc. 



dies. On the other hand, Professor Stone is consistently 

 and effectively directing attention to the fact that a condi- 

 tion of health is the natural or normal thing with the plant, 

 and that if we as cultivators do our part b}^ making the 

 conditions right for the normal development of the plant, 

 many of these troublesome problems of disease are thereby 

 solved in advance. 



Here, then, are three fundamental ideas which your three 

 Massachusetts teachers have respectively emphasized : — 



1. Understanding of cause is necessary to the most effect- 

 ive application of remedy. 



2. If the cause is a parasite, no pains is to be spared until 

 every stage of its development is understood. 



3. The first essential in the prevention of plant disease is 

 to supph^ the plant with the conditions for its best normal 

 development. 



Certainly it would be hard to define a fourth point to be 

 entered in the same class with these. What I shall have to 

 say may be regarded rather as tlu'owing a side light upon 

 each of them in turn, — a light which I trust will in the end 

 make all of these three points stand out in fuller clearness, 

 and at the same time fuse their respective messages into a 

 common one, and bring this home more clearly to the plant 

 cultivator. 



M}'^ aim in this forenoon's conference will be to make clear 

 my conviction that, if you are to understand the maladies of 

 your plants as practical cultivators seeking to know cause 

 and remedy, you must study them not as isolated diseases, 

 but alwa3\s as having intricate relationships. These relation- 

 ships are, moreover, of two general classes : — 



First, there are the interrelationships between the differ- 

 ent diseases which attack the same plant. Misfortunes sel- 

 dom come singly, bug and blight and rot co-operate in their 

 havoc ; and, while the scientist may study them singly, the 

 cultivator who w^ould save his plant must fight them in the 

 aoro-reo;ate. 



Second, there are the relationships with the plant, not 

 merely at the moment of attack, but such as can be under- 

 stood only by a consideration of the particular nature of the 



