260 STATE HORTICULTURAL SOCIETY. 



SECOND STAGE OF YELLOWS. 



Following the appearance of the disease in the fruit, it shows itself by 

 the development of small,wiry twigs (Fig. 8,4), commonly spoken of as a fun- 

 gous growth. While these frequently do not appear until after the tree has 

 given a crop of premature fruit, a tree showing the twigs will always bear 

 diseased fruit. As a rule, if only a small portion of the fruits are prema- 

 ture, the wiry, starved growth will not show until the following season, 

 although they may appear in the autumn on the trees that were healthy 

 the previous year. These shoots grow in clusters (Fig. 8, 4) upon any part 

 of the tree, but generally are most numerous upon the main branches and 

 near the forks. Sometimes they are straight and unbranched, but, as a 

 rule, especially late in the season, they are branched, the buds in the axils 

 of the leaves making a premature growth the same season they are formed. 

 The shoots are often short-jointed and form thick tufts. The leaves are 

 small, being about half as long and wide as healthy ones, and have a 

 yellowish tinge. The buds are small and generally winter-kill, as the 

 shoots do not mature their growth. 



Another way that it appears, is when apparently healthy trees send out 

 in the autumn the small shoots distinctive of yellows, with the pale yellowish- 

 green foliage. The trees show the same symptoms the second year as 

 were noticed the first, and in addition the fruit, if any is borne, is small, 

 both in size and quantity, bitter in taste, or at least of inferior flavor. All 

 of the tree is now generally involved, and the foliage is quite yellowish 

 and even red in color and considerably curled, particularly on the shoots 

 sent out in the spring. Sometimes the tree dies the second year, but it is 

 usually the third, or perhaps the fourth year that it finally succumbs. The 

 diseased shoots are quite brittle and seem to have little life. There are no 

 well-authenticated cases of recovery from this disease. After a tree affected 

 with yellows has been removed, it is a common practice to set a young 

 tree in its place, and no harm has been noticed from replanting the spring 

 following the removal of the diseased tree. In case the affected tree was 

 left long enough to transmit its contagion to the neighboring trees, there 

 would undoubtedly be danger of the newly planted tree becoming in time 

 infected by its diseased neighbors, but at any rate the young tree would be 

 less likely to be attacked than other trees in the orchard. In practice, with 

 prompt removal of diseased trees, there seems to be no danger in replant- 

 ing the next year, and peach orchards of recent years have suffered but 

 little from yellows, when steps were taken to promptly eradicate the disease 

 as soon as it appeared. This indicates that, up to the time of its outward 

 manifestation, the disease is not readily transmitted. 



YELLOWS FROM DISEASED PITS AND BUDS. 



While there can be no question that the disease can be communicated to 

 nursery stock by the use of pits or the buds from diseased trees, we 

 believe there is less danger of introducing yellows into a locality in this 

 way than by means of nursery trees grown in the vicinity of diseased 

 orchards, or where the trees themselves were from healthy stocks but were 

 infected by neighboring nursery trees which may have acquired the dis- 

 ease either through the pit or bud. In the experiments of Dr. Smith, less 

 than one pit in a thousand, from premature peaches, grew, but there may 



