19.]
DISEASES OF THE VINE.
I cannot agree with Mr. FULLER that the diseases of the vine are not
formidable in this country. They are so formidable that they threaten
to destroy some varieties altogether; and the Catawba, once the glory
and pride of the Ohio vineyards, has for the last fifteen years
suffered so much from them, that many of the grape-growers who are too
narrow-minded to try anything else are about giving up grape-growing in
despair.
It is very fortunate, therefore, that we have varieties which do not
suffer from these diseases, or only in a very slight degree; and my
advice to the beginner in grape-culture would be, "not to plant largely
of any variety which is subject to disease." Men may talk about
sulphuring, and dusting their vines with sulphur through bellows; but I
would rather have vines which will bear a good crop without these windy
appliances. We can certainly find some varieties for _every_ locality
which do not need them, and these we should plant.
The mildew is our most formidable disease, and will very often sweep
away two-thirds of a crop of Catawbas in a few days. It generally
appears here from the first to the fifteenth of June, after abundant
rains, and damp, warm weather. It seems to be a parasitic fungus, and
sulphur applied by means of a bellows, or dusted over the fruit and
vine is said to be a partial remedy. Close and early summer-pruning
will do much to prevent it, throwing, as it does, all the strength of
the vine into the young fruit, developing it rapidly, and also allowing
free circulation of air. In some varieties--for instance, the
Delaware--it will only affect the leaves, causing them to blight and
drop off, after which the fruit, although it may attain full size, will
not ripen nor become sweet, but wither and drop off prematurely. In
seasons when the weather is dry and the air pure, it will not appear.
It is most prevalent in locations which have a tenacious subsoil, and
under-draining will very likely prove a partial preventive, as excess
of moisture about the roots is no doubt one of its causes.
The gray rot, or so-called grape cholera, generally follows the mildew,
and I think that the latter is the principal cause of it, as I have
generally found it on berries whose stems have been injured by the
mildew. The berry first shows a sort of gray marbling; in a day or two
it turns to a grayish-blue color, and finally withers and drops from
the bunch. It will c
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