New York Agricultural Experiment Station. 177 



ing the least trace of the disease be rejected; for, although we 

 have never seen any ill etfects from the planting of affected 

 apple trees, it appears probable that the disease may thus be 

 spread to other fruits like peaches and red raspberries which 

 are sometimes much injured by it. 



A nurseryman in Wayne Co. writes as follows: "Two 

 years ago we planted a row of apple trees affected with crown 

 gall beside a row of healthy trees. This fall we dug up a num- 

 ber of the trees and some had galls on them and some had not. 

 The trees with the crown gall made just as good a growth as the 

 healthy trees near by, the root system seemed to be healthy and 

 supplying the top with all the nourishment needed for a strong 

 growth." 



" Hairy Eoot." — While examining nurseries for crown gall 

 we came across a nursery trouble of apple trees which nursery- 

 men call " hairy root." Affected trees have fev/, if any, large 

 branch roots. The root system consists of a multitude of very 

 small roots which spring in rosettes from the somewhat thick- 

 ened main root, giving it a bushy or hairy appearance. (See Plate 

 XXIII.) Affected trees are worthless for planting. 



One -nurseryman tells us that he has known this trouble for 50 

 years; another has known it 40 years; and it appears that many 

 nurserymen are more or less acquainted with it. Yet we have 

 never seen any published account of such an apple disease. 

 While specimens of it are occasionally found in the majority of 

 the nurseries in Western New York, we have not heard of any 

 nursery where it is sufficiently abundant to cause appreciable 

 loss. Perhaps, one tree in each 500 may be affected with " hairy 

 root." Nurserymen are pretty generally agreed that the disease 

 shows itself on the seedlings and is much more common among 

 Western-grown seedlings than among home-grown ones. The 

 affected seedlings are usually rejected at the grafting bench, but 

 some are passed only to be discarded later when the trees are dug 

 for market. 



A tree affected with " hairy root " may at the same time suffer 

 from attackfi of woolly aphifi or crown gall or both, but in the 

 12 



