18 N. J. Agricultural Experiment Stations Bulletin 356 



several which produced typical little-peach fruits throughout their 

 entire lengths. Buds were cut from the yellows and little peach parts 

 of the trees and propagated in the nursery. Several trees from each 

 source were secured and planted out in orchard form in 1920. It 

 is too early to determine whether the diseases will propagate distinct 

 from each other from this tree. 



Factors Producing Symptoms Similar to Yellows and 

 Little Peach 



Symptoms practically identical with those characteristic of yellows 

 are frequently due to other causes. This fact throws more or less 

 doubt on all the early records and on many of the later reports of 

 the occurence of yellows, and no doubt accounts for the supposed re- 

 covery of trees said to have been affected with yellows. The most 

 common causes of these symptoms are : 



(a) Girdling by borers or mice. 



(b) Injuries due to climatic factors. 



(c) Mechanical injuries, including label wires. 



(d) Improper fertilization with plant-foods. 



(e) Lack of or improper cultivation. 



(f) Other plant diseases. 



(g) Unfavorable soils. 



It is very probable that many of the reports and records of the 

 occurrence of peach yellows are the results of incorrect diagnosis and 

 that the symptoms were due to some of the causes indicated above. 

 No doubt many trees supposedly affected with yellows have been de- 

 stroyed. Peach "Buttons" 



In seasons following cold or severe weather many varieties of 

 peaches may produce a number of small fruits or "buttons" which 

 cling to the tree throughout the season but fail to develop to a size 

 much larger than a hickory nut. The J. H. Hale variety does this 

 quite frequently, but whether because of winter injury alone or be- 

 cause of faulty pollination, or both, is uncertain. Palmer suggests 

 that these "buttons" are due to improper pollination. He believes that 

 pollen of St. John and other varieties, including J. H. Hale, is impo- 

 tent to a considerable degree varying with the season. Connors 2 has 

 noted at the New Jersey Agricultural Experiment Station that the 

 anthers of J. H. Hale and some of the seedlings in the breeding ex- 

 periment are in such condition as to suggest the possibility of partial 

 or complete impotency of the pollen ; but whether this is normal to 



2 Unpublished data. 



