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be prevented by sheltering the foliage. How far expedients for this purpose 
can be profitably employed is a question for grape-growers to decide. The sim- 
plest form of covering is a board-covered trellis, and for amateur culture or pri- 
vate family use the expense of such covering is not worthy of consideration. 
“It is also well known that sulphur applied occasionally during the period of 
growth will prevent mildew; as a simple statement this has some value, but it 
is not sufficiently definite to enable the vine-grower to determine the extent or 
frequency of the applications necessary to secure a crop. Some seasons occur 
during which there is no necessity to apply remedies, and there is no periodical 
certainty in any as to when mildew may appear. Could we foresee its approach, 
so that preventive applications might be made at the proper time, and only at 
that time, the practice would then be reduced to a definite system, and be pro- 
portionately valuable. 
«This knowledge can be reached only by aseries of exact hygrometric obser- 
vations made in various grape-growing localities, under the general supervision 
of an experienced vegetable physiologist. It may be well to remark that the 
system of training hardy varieties to the top of the trellis, for the purpose of 
sheltering the more tender and valuable varieties below, has been suggested, and 
to a certan extent acted upon with favorable results. The ultimate effect of 
mildew is to check and retard growth, and thereby prevent proper maturity of 
the wood. 
“For all cultural purposes it is sufficiently accurate to assume that the hardi- 
ness of a grape is simply its immunity from mildew. 
“When a grape is said to be too tender for our winters we may safely con- 
clude that, in other words, it is so subject to mildew that the growth fails to 
reach proper maturity. 
« Fruit-growers, above all others, should learn to call things by their proper 
names. 
“TJ have reason to believe that all the foreign wine grapes would withstand 
our winters if not checked by mildew during growth. I have exposed matured 
growths of Black Hamburg, Muscat of Alexandria, Golden ( hasselas, the Fron- 
tignan, and other foreign varieties, to a frost several degrees below zero, without 
being injured. 
« And all of our native varieties, excepting, of course, strictly southern species, 
are sufficiently hardy to stand over ordinary winters if kept in health during 
summer. It is important to keep this in view. 
«T have already remarked that downy-leaved grapes are more subject to mil- 
dew than those whose leaves are smooth. The Fox family of grapes, Vedes 
labrusca, from which most of our popular cultivated varieties have been pro- 
duced—such as Isabella, Catawba, Diana, Rebecca, Concord, Iona, Ives’s Seed- 
ling, &¢.—are more subject both to mildew and rot than varieties of the summer 
grapes, Vitis estivalis, or the frost grape, Vitis cordifolia. 
“T have long since expressed my conviction that more attention should be 
given to the improvement of the two last named species for wine grapes than 
has hitherto been done. | 
“ For northern latitudes the Vetis cordifolia, of which the Clinton is a familar 
example, is worthy particular attention, not only on account of its intrinsic’ 
merits as a wine, and even as a table grape, but as a representative of a class of 
great hardihood and freedom from disease. Occasionally we may observe mil- 
dew on the Clinton, on the upper surface of the foliage, but I have never seen 
it to obtain sufficiently so as to materially affect growth, and rot in the berry I 
have never seen. The leaf of this variety is green and smooth on both surfaces. 
«For more southern climates the varieties of Vitis estivalis will be suitable ; 
among these may be mentioned Norton’s Virginia Seedling, Herbemont, Lenoir, 
and Cynthiana. These comprise some of our best wine grapes, but require a 
longer season to attain maturity than many of the Fox family, and will not reach 
