THE PEACH. 
599 
We consider the contagions nature of this malady an unset 
tied point. Theoretically, 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 practically 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.* 
Cause of the Yellows. No writer has yet ventured to assign 
a theory, supported by any facts, which would explain the cause 
of this malady. We therefore advance our opinion with some 
diffidence, but yet not without much confidence in its truth. 
We believe the malady called the Yellows to be a constitu- 
tional taint existing in many American varieties of the peach, 
and produced, in the first place, by bad cultivation and the con- 
sequent exhaustion arising from successive over-crops. Afte - 
wards it has been established and perpetuated by sowing the 
seeds of the enfeebled tree either to obtain varieties or for 
stocks. 
Let us look for a moment into the history of the peach cul- 
ture in the United States. For almost a hundred years after 
this tree was introduced into this country it was largely culti- 
vated, especially in Virginia, Maryland, and New Jersey, as we 
have already stated, in perfect freedom from such ' disease, and 
with the least possible care. The great natural fertility of the 
soil was unexhausted, and the land occupied by orchards was 
seldom or never cropped. Most of the soil of these States, 
however, though at first naturally rich, was light and sandy, and 
in course of time became comparatively exhausted. The peach 
tree, always productive to an excess in this climate, in the im 
* The following extract from some remarks on the Yellows by thai 
careful observer, Noyes 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 con- 
tagion, but breaks 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 con- 
siderable number of trees, it does not attack all at once. It breaks out 
in patches which are progressively enlarged, till eventually all the trees 
become victims to the malady. Thus in an orchard of two and a halt 
acres, all the trees were healthy in 1827. The next year two trees on 
the west side of the orchard, within a rod of each other, took the Yellows. 
In 1829, six trees on the east side of the orchard were attacked; five of 
them standing within a circle of four rods diameter. A similar fact is now 
apparent in my neighbourhood. 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 cortiguous to 
each other ; while all the other trees are free from any marks of disease.” 
— Cultivator. 
