THE DISEASES OF THE PEACH TREE. 39 



truded from the extremities, but from latent buds on the main portions of the 

 stem and larger branches. The leaves are very narrow and small, quite distinct 

 from those of the natural size, and are either pale yellow or destitute of color. 



2. The premature ripening of the fruit. This takes place from two to four 

 Aveeks earlier than the proper season. The first season of the disease it grows 

 nearly to its natural size; the following season it is not more than half or a 

 fourth of that size ; but it is always marked externally (whatever may be the 

 natural color) with specks and large spots of purplish red. Internally the flesh 

 is more deeply colored, especially around the stone, than in the natural state. 



Either of the foregoing symptoms (and sometimes the second appears a 

 season in advance of the first) are undeniable signs of the Yellows, and they 

 are not produced by the attacks of the worm, or other malady. We may add 

 to them the following additional remarks: — 



It is established beyond question, that the Yellows can always be propagated 

 by budding or grafting from a diseased tree; that the stock, whether peach or 

 almond, also takes the disease, and finally perishes; and that the seeds of the 

 diseased trees produce young trees in which the Yellows sooner or later breaks 

 out. To this we may add that the peach, budded on the plum or apricot, is 

 also known to die with the Yellows. 



Very frequently only a single branch, or one side of a tree, will be affected 

 the first season. But the next year it invariably spreads through its whole 

 system. Frequently trees badly affected will die the next year. But usually 

 it will last, growing more and more feeble every year, for several seasons. The 

 roots, on digging up the trees, do not appear in the least diseased. 



The soil does not appear materially to increase or lessen the liability to the 

 Yellows, though it first originated, and is most destructive, in light, warm, 

 sandy soils. 



Lastly, it the nearly universal opinion of all orchardists that the Yellows is 

 a contagious disease, spreading gradually, but certainly, from tree to tree 

 through wlvole orchards. It was conjectured by the late William Prince that 

 this takes place "when the trees are in blossom, the contagion being carried 

 from tree to tree in the pollen by bees and the wind. This vievv' is a question- 

 able one, and it is rendered more doubtful by the fact that experiments have 

 been made by dusting the pollen of diseased trees upon the blossoms of healthy 

 ones without communicating the Yellows. 



We consider the contagious nature of this malady an unsettled point. Theo- 

 retically, we are disinclined to believe it, as we know nothing analogous to it 

 in the vegetable kingdom. But on the other hand it would appear to be prac- 

 tically true, and for all practical purposes we would base our advice upon the 

 supposition that the disease is contagious. For it is only in those parts of the 

 Atlantic States where every vestige of a tree showing the Yellows is immediately 

 destroyed, that we have seen a return of the normal health and longevity of the 

 tree.* 



♦The following extract from some remarks on the Yellows by that careful observer, Xoj-es Darling, Esq., 

 of New Haven, Ct., we recommend as worthy the attention of those who think the disease contagious." They 

 do not seem to indicate that the disease spreads from a given point of contagion, but t)reaks out in spots. 

 It is clear to our mind that in this, and hundreds of other similar cases, the disease was inherent in the trees, 

 they being the seedlings of diseased parents. 



" When the disease commences in a garden or orchard containing a considerable number of trees, it does 

 not attack all at once. It breaks out in'patches which are progiessivvly enlarged, till eventually ail the trees 

 become victims to the malady. Thus, in an orchard of two and a half acres, all the trees were healthy in 

 1S27. The next year two trees on the west side of the orchard, within a rod of each other, took the Yellows. 

 In lS2y, sis trees on the east side of the orchard were attacked ; live of them standing within a circle of four 

 rods diameter. A similar fact is now apparent in my neighborhood. A fine lot of 200 young trees, last year 

 in perfect health, now show disease in two spots near the opposite ends of the lot, having exactly six 

 diseased trees in each patch contiguous to eac& other ; while all the other trees are free from any marks of 

 disease."— C«/iii.-ato;-. 



