The Wheeling daily intelligencer. [volume] (Wheeling, W. Va.) 1865-1903, 1872-04-01

MnDEw on GRAPE vNEa-The follow.

mILDRW ON GRAPE VNEs.-The follow.
Ing < Is the communication in regard tc
mildew on grape vines, from DR.. William
;. Charming, read at the regular meeting
Of Rhode Island Horticultural Society, on
Wednesday evening, 27th inst,
Il WASHINGTON, D. O., Feb. 20, 1879.
Charles II. Smith, Esq., Secretary of Mt
| Rsods Bland Horticultural SOeetv.
DEAR SrR-I obeserye that tho grape
vine will be under discussion at the Feb.
ruary meeting Of the Horticultural Soci.
ETY.. isi... N man 'i.lE .7s3s
] 1 wish 10, bring to the notice ofihe SO.
ciety some very important results In rela.
tion 70 the mildew Of the vine, both
American and European, obtained re.
Gently by Prof. Taylor, who Is conducting
the microscopic Investigation into the
fungold diseases Of plants at the Depart.
ment Of Agriculture.
Prot. Taylor has traced the variety Of
eryaphe, which constitutes the European
mildew, through oil It's stages, (Oidium in.
clusive) on the European grape vines in
the conservatory Of the Department, and
he has found the ripened concepticle or
fruit on oil parts Of last years growth. II
piece Of last years cane Is brought into
a warm atmosphere, the erysiphe begins
TO develop from the seeds or pores. No
matter, therefore, how closely q vine Is
trimmed, enough wood Is left upon II to
carry the seeds Of the mildew over to
another year. As q consequence Of this
discovery, the stems and branches of oil
the foreign grape vines in the conserva.
tory Of the Department have been wash
ed over this winter with u carbolic pre-,
paration. i- a. ''- ~ ~ rif''fti
All OF our friends who have cold grape.
ries may be interested in trying the same
experiment. A solution of snlphuret OF
lime, as 1t is properly called, or carbolic
soap would undoubtedly destroy these
spores on the wood. l would propose
whitewashing for the same purpose.
Prot. Taylor suggests that the same pre-
caution would destroy the eggs or thrips
on the bark.
Another observation of interest in rela
tion to the European mildew is the follow.
ing: Prof. Taylor found that the mildeW
on leaves pressed in a dry book rapidly
spread and grew. He therefore suggested
the experiment Of keeping the grapery of
the Department very dry for lew days.
This resulted in so rapid development of
the European mildew (ETysiphe Tuckeri)
that he obtained for the first time either
in Europe or America the perfectly rlpen-
ed C0ncepticles or fruit OF that VARIETY
It follows that the European mildew is
developed by drg heat, while the Ameri.
can mildew (another iungus) requires moist
heat. Our cultivators OF cold graperies
may take hint from this.
But Prot. Taylor's observations cover
also the history OF the American mildew,
which is chiefly the 6otrytis oiticOld. On
the wood Of last years growth, he finds
the mtceleum or cobweb-like branches of
this pest, capable Of resuming active
growth when subjected to warmth and
moisture. Here, again, whitewashing or
solutions Of sulphrets or carbolic acid,
applied to the wood in winter will de.
stroy the buds Of tho. .mildew, which are
awaiting only the heat of another sum.
mer to spread over: the new canes and
leaves.
There is also an American variety of
e1ysiphe, which appears so late on the
vines as hardly to affect the fruit. But
this may probably iniure the buds of the
following. year. Prof. Taylor has found
the concepticles Of this mildew on, the
wood Of the American vines, under the
same condition as the European. These
also can. be destroyed by washes applied
to the vines in winter. m rods "a
Accepting this view of the annual prop.
agation Of mildew, there is one other
precaution which may be taken by grape
growers. This. Is to carry off and destroy
tho last years leaves and trimmings,
which may be regarded as storehouscs OF
latent mildew. Truly yours,
rr. WIN. +. CHANNING.