MR. M. DUNN ON THE EXTtRPATFON OF THE VrNE-PEST. 83 
until tliey broke into growth in April, which they did in a most 
satisfactory manner and made strong growth during the summer, 
never showing the least sign of an insect during the whole season 
on either root or stem. 
One vinery I treated as above described ; but finding the roots 
of the vine in the other to be in a much healthier state and not 
nearly so badly infected with insects, I did not think it necessary 
to lift them and subject them to such severe treatment, hoping 
that I might find out some liquid mixture that I might apply to 
the soil and that would destroy the insects without killing the 
roots, or having to be at the trouble of lifting and cleaning them. 
The vine-house and all above the ground I thoroughly cleaned in 
the same manner as the first house, and applied different liquid 
mixtures to the soil and roots w^henever I had an opportunity and 
thought they would bear it, in hopes of being able by that means 
to exterminate the insects. All went on well until the beginning 
of June, about seven weeks after they started into growth, when 
the insects began to appear on the young wood and leaves as well 
as on some pot-vines trained against the back wall; and on ex- 
amining the roots I found them literally swarming with insects. 
The roots of the pot-vines being equally bad, I at once turned 
them out to the rubbish-heap and burned them remorselessly, 
leaving six to experiment on with the different solutions during 
the summer. I increased the strength of the liquid mixtures 
until the vines began to flag and show signs that they could bear 
no more and live ; but still the insects lived and increased, if any- 
thing, on the roots, except in one place where I had watered with 
salt and water, at ten ounces of salt to the gallon of water, which 
I increased to twelve ounces to the gallon, and found it effective 
in keeping the insects from increasing without hurt to the vine- 
roots. 
Having killed some of the pot-vines by using too strong solu- 
tions, I did not feel justified in experimenting further, but deter- 
mined to try and keep the insects in check as much as possible 
until they were again at rest, and then thoroughly clean both 
tops and roots in the same manner as I had done those in the 
other house in the previous winter, and which had gone on most 
satisfactorily ever since and kept perfectly clean of insects. So 
as soon as the crop was cut and the vines at rest (in December 
1868), I treated them in every particular the same as I had done 
those in the other vinery and with equally good results. They 
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