660 THE FRUIT INDUSTRY ix XEW YORK STATE 



important distinction must be made between a fibrous-rooted 

 tree and one affected by hairy root ; a sharp distinction must also 

 be made between warts or pirnples on the root of the tree, and 

 crown gall. The one is not injurious; the other may be. in 

 other words, it takes an expert to decide whether a tree is 

 affected by a disease or merely carries a blemish. 



In New York, even trees affected by hairy root and crown gall 

 have grown just as well as those which were not affected ; further 

 south, this condition may not be true. The reader is referred to 

 Bulletin 186, " Field Studies of the Crown Gall and Hairy 

 Boot," by Hedgcock, also to Bulletins 213 and 255, by Dr. E. F. 

 Smith, published by the Bureau of Plant Industry, U. S. Depart- 

 ment of Agriculture, Washington, D. C. 



One other important disease which may attack root and branch 

 is fire blight. No other means than the absolute removal of the 

 affected tree seems to be of value. 



Powdery mildew is controlled by spraying with lime-sulphur 

 to which sulphate of iron has been added. 



Scab on apple and shot-hole fungus on the cherry, and a 

 number of other diseases of the leaves are controlled by spraying 

 with lime-sulphur or bordeaux mixture.* 



HISTORY 



Within the past fifty years the commercial nursery came into 

 being. William Prince of Flushing, L. I., is regarded as the 

 pioneer of the industry. In 1825 his son issued quite a com- 

 prehensive catalogue listing several hundred species and varieties. 

 The development of commercial orchard plantings in Xew York 

 stimulated this branch of the nursery industry. 



Sixty years ago no city in the United States had purchased an 

 acre of land for park purposes; by 1899 there were probably 

 75,000 acres of city parks upon which $11,000,000 per year were 

 expended for maintenance and improvement, and the increase 

 since that time has been remarkable. 



In the eastern nurseries the attention given to ornamentals is 



* See Some Important Leaf Diseases of Nursery Stock, Cornell Bulletin 

 No. 358; The Yellow-leaf Disease of Cherry and Plum in Nursery Stock, Cor- 

 nell Circular No. 31; The Tarnished Plant Bug, Cornell Bulletin No. 346. 



