286 MINNESOTA STATE HORTICULTURAL SOCIETY. 
easily covered with boards or cheap cloth, and thus the injury from this 
pest averted. If I am correct that the germs or spores of mildew are gen- 
erated in the ground or on its surface, then would not any substance 
that would cover the ground, and in which germs or spores could not gen- 
erate, be a preventive of mildew? Covering the ground with lime or 
ashes, or having a thick crop of grain growing upon the grounds a few 
inches high, just before these germs are generated, might also possibly 
prove a preventive. 
REPORT OF COMMITTEE ON GRAPE INSECTS AND DISEASES. 
J. S. HARRIS, LA CRESCENT. 
Gentlemen and Members of Minnesota State Horticultural Society: 
It is evident that Minnesota contains many of the best sites for grow- | 
ing many of the hardy native grapes, and her soil and climate bring a 
larger size, brighter color, and sprightlier flavor, than any other portion of 
the American continent; and that the vines are more nearly free from rot, 
mildew, and the ravages of injurious insects, than in any other part of this 
country; still, we do not always have perfect immunity from them. In 
some seasons, there have been cases of mildew, and brown and black rot, 
but generally it has appeared only in vineyards that were neglected, or 
that were so located that they had imperfect air circulation, or in some in- 
stances where too severe or late Summer pruning had been given the pre- 
vious year. The most troublesome insect hus been the little steel blue or 
grape vine flea beetle [Graptodera chalybea, Ill.] The beetle is small, 
measuring less than one-fifth of an inch in length. Its color is dark steel 
blue. The characteristic which is at once noticed, is its habit of jumping 
like a flea. The damage done by the mature beetle is by eating into the 
buds in early spring, and later gnawing holes into the leaves. 
Later in the season the brown, sluggish larva appears upon the upper 
sides of the leaves, eating holes in them, and frequently skeletonizing 
them. ~ 
The adult beetles pass the winter under the rough bark of supporting 
posts, under the outer bark at the base of the older vines, in the crevices of 
wooden trellises, joints of adjoining fences, and under sticks, stones, and 
other rubbish upon the ground,or in any place that will afford them shel- 
ter. During the first warm days of spring, as the buds are beginning to 
swell, these pests leave their winter quarters, and in the middle of the 
day find their way to the nearest vines. They have voracious appetites, 
and atonce begin gnawing unsightly holes into the buds: and in vineyards 
where they are numerous dozens of buds upon every vine are thus de- 
stroyed. Upon one side of my own vineyard I have had the damage so 
great as to reduce the following crop of fruit one-half, and I have heard 
of some instances in this county (Houston), where the damages were so 
great as to cause nearly a total failure of the fruit and serious injury to 
the vines. 
After their first hunger is satisfied the beetles pair, and as soon as the 
leaves have unfolded the females begin to deposit their eggs. The eggs 
