120 MASSACHUSETTS HORTICULTURAL SOCIETY. 



the doing or not doing of certain things. Along with what I shall 

 say today, I would have you remember that plant pathology is a 

 very new science, of which as yet we barely know the rudiments. 



Every year, however, adds to the sum of our exact knowledge, 

 and it will not be long before those growers who learn and apply 

 this new knowledge will outstrip their fellows, and have the field 

 to themselves. Competition is not likely to decrease, nor are 

 prices likely to advance very much, and tlie profits must come 

 from avoiding losses. 



It is particularly to this enterprising class of men that I should 

 like to speak concerning the restriction of plant diseases. In 

 this art, as in that of modern medicine, an ounce of j)revention is 

 worth many pounds of cure. There are at least three classes of 

 growers : First, those who never learn anything except by bitter 

 personal experience. To such men, and I may be speaking to 

 some of this type today, much of this address may seem theo- 

 retical and impracticable. The loss of one or two crops in suc- 

 cession by the attack of some preventable parasite usually affords 

 such a man the needed personal stimulus, and thereafter, as far 

 as my own experience with such men goes, he is a faithful con- 

 vert. There is a second class of growers who believe it all, 

 know it all, and can give pointers to any expert, but are what 

 might be called eleventh-hour men. Whether from inertia, love 

 of ease, or inability to plan, they never get around to try any 

 preventive until the mischief is done. Such men are the worst 

 to deal with, since they are pretty certain to apply some remed}^ 

 when it is too late, and equally certain to declare afterwards that 

 all such remedies are worthless, as they know from " personal 

 experience," having tried them. There is a third class of growers 

 who are very quick to see and equally quick to apply anything 

 likely to add to their pecuniary profit. Probably no country in 

 the world has more men of this type than our own. They are 

 the men wliose hard common sense will try what stuff the 

 specialist's fine-spun theories are made of, and woe to him if 

 he is a quack, for they will surely find him out ! It is this 

 class of men whom I most fear, and at the same time most desire 

 to reach. 



I may take for granted that all of you already know that dis- 

 eases which prevail extensively, and are known as contagious 

 or •' catching " diseases, are due to parasites. This is true not 



