-^6 THE CULTIVATION OF THE 



carried from tree to tree through diseased seed, through 

 diseased buds, through proximity of soil, and even by 

 pruning instruments going from diseased to healthy 

 trees. So much am I impressed by this suspicion, that 

 I would not haul young trees in a wagon, which had 

 shortly before, hauled the cuttings from pruning a 

 diseased orchard, unless the wagon had been fumigated. 

 I believe this disease-germ may be both in the soil and 

 in the tree, after the soil and tree have been placed by 

 circumstances in a condition to develop it, and for this 

 reason I would not plant a new orchard, at once, on 

 the site from which a diseased orchard had been removed. 

 I believe ploughing and fertilizing, and one year of 

 upturned exposure without cropping, will be apt to 

 destroy the disease-germ, and peaches might be planted 

 again, but I should never recommend this plan if other 

 land were available. Now as to the conditions favorable 

 to the production of this germ of Yellows, I believe it 

 is most likely to be developed where peaches have been 

 planted in one locality in large numbers for a series of 

 years, where orchards have been cropped after their 

 second year, where culture and fertilization have been 

 neglected or omitted, and where the land had previously 

 been made rich (and was so when the trees were 

 planted) by lime and barn-yard or stable manure, where 

 the trees have been raised from the seed of budded 

 trees, and thus have been propagated back and not 



