ANNUAL REPORT OF NEW YORK 
116 
These several kinds of destroyers of the plant lice were everywhere com¬ 
mon upon the hop vines the past Summer. I believe that in every instance 
in which leaves with the lice upon them were sent me by correspondents, 
I found one or more of these destroyers also upon the leaves ; and in one 
box that came to me, not one of the lice was remaining, all having been 
devoured by several of these enemies which had happened to be inclosed 
in the box. These destroyers having been so common, it is quite probable 
that they have now subdued these lice to such an extent that the coming 
season the crop will be much less if at all damaged by them. 
It is of great importance that we should have some remedy, whereby, 
when these insects do fall upon the hop vines in such myriads as they have 
done the past two years, we may be able to promptly destroy them. 
As the lice remain stationary upon the undersides of the leaves and are 
so very tender and delicate that the slightest pressure suffices to crush and 
kill them, Mr. Kirby recommends to take the leaf between the thumb and 
finger, and move the finger so as to gently rub over the under surface of 
the leaf, whereby every aphis upon it will be destroyed. He thinks women 
and children can be employed for a small compensation to do this work, 
taking every leaf in succession between the thumb and finger, and thus 
wholly ridding the vines from these vermin. But we all know it will be an 
immense labor to thus take hold of every leaf upon the vines occupying 
whole acres of ground. Many of the lfeaves, too, are quite large, being five 
or six inches broad, and the finger is but three inches long. It will there¬ 
fore require one hand to hold the leaf steady, whilst the thumb and finger 
of the other are drawn several times along it, mowing down the vermin 
by successive-swaths. Moreover, the veins on the underside of these large 
leaves are studded with prickles, whereby I doubt if a dozen leaves can 
thus be rubbed over before the skin of the finger will be cut through to the 
quick. I need not specify other obstacles which occur to my mind, all con¬ 
curring to convince me that this proposed remedy, of the success of which 
Mr. Kirby is quite sanguine, is wholly impracticable. 
Washing and syringing the plants with strong soap suds has been often 
recommended for destroying the aphis upon them. I have recently been 
experimenting with this remedy, upon the plant lice which so badly infest 
the beautiful verbenas of our Flower Gardens, and I find it to be of but 
partial efficacy. It only kills the young, tender lice ; those which are ma¬ 
ture are so robust that they are not destroyed, even though the infested 
stems and leaves arc immersed in a strong solution of soap. 
There is one remedy, and one only, which we know to be efficacious and 
perfectly sure for destroying the different species of plant lice. This is the 
smoke of tobacco. It operates like a charm. It never fails. But to apply 
it, it is necessary to place a box or barrel over the plant, burning the 
tobacco in a cup underneath, until its smoke has filled the inclosed space 
and penetrated all the interstices between the leaves. Hereby the rose 
bushes and other shrubs and plants in our gardens are with ease wholly 
cleansed from these vermin. To render it available for destroying these 
insects upon the hops, probably a piece of canvas or other large cloth can 
be thrown over them or some other apparatus devised whereby they can be 
fumigated for a few moments in the same thorough manner. 
