130 MASSACHUSETTS HORTICULTURAL SOCIETY. 



country to the other. Many examples might be adduced. The 

 most notorious recent one in this country is the wholesale distri- 

 bution of the pestiferous San Jose scale in the eastern United 

 States by two New Jersey nursery men. More than this, some 

 dealers appear to be still sending out infested trees in spite of 

 claims to the contrary. There is no good reason why all of this 

 nursery stock should not be fumigated in a dormant condition, 

 [f done properly the scales would be destroyed without injury to 

 the plants. The only safety for growers appears to be in demand- 

 ing this, and in refusing to accept any trees or other plants which 

 are not clean. The damage to an orchard which is certain to result 

 from the introduction of a single tree infested with the San Jose 

 scale is so great that it becomes every fruit grower to be on his 

 guard. The white scale or West Indian scale of the peach is also 

 very destructive and should be guarded against with great care. 

 If by any accident it should be as widely distributed from nur- 

 series as the San Jose scale has been, it would injure the peach 

 orchards to quite as great an extent, a few years sufficing to de- 

 stroy the most robust trees. I have sometimes called it the 

 " whitewash scale " because at a little distance affected trees look 

 as if covered with lime. 



GrENEKAL CONCLUSIONS RESPECTING PREVENTIVE MEASURES. 



1. Prompt Bemoval and Destruction of Diseased Material. — 

 There are special reasons for this, owing (a) to ability of many 

 parasites to grow and fructify on the plants, or parts of plants, 

 which they have already destroyed, i.e., to live as pure sapro- 

 ])hytes, and (b) to the persistent vitality of many other sorts 

 under what would seem to be very unfavorable conditions, e.g., 

 after being dry for months. The fusarium of watermelon grew 

 from a dried-out laboratory culture after tAvo and one-half years. 



Practical application in : 



(1) Field. — Pear blight, rot of stone fruits, lemon scab, black 

 knot of plum and cherry, peach yellows, San Jose scale (when 

 restricted to a few trees). 



(2) Greenhouse. — Rust of chrysanthemums and carnations, 

 spot of violets, rot of lettuce, black spot of roses, anthracnose 

 and timber rot of cucumbers, wet rot of hyacinths, etc. 



It is not enough to pick off the diseased parts. They must be 

 disposed of properly. Loss may result from throwing diseased 



