The Daily state journal. [volume] (Alexandria, Va.) 1868-1874, 1872-09-13

vegetable Blight.
AT the recent meeting of the Potomac
Fruit Growers Association, Professor John
Brainerd read the following paper upon
Vegetable Blight, which was abundantly
illustrated by diagrams, drawn with minute
correctness by his own hands, enabling
those present to readily catch his ideas and
properly understand the detail of the vege-
table and insect operations causing decay
in leaf and fruit:
Immediately after submitting my report
on the examination Of grape leaves and
fruit, presented for that purpose at the last
(July) meeting Of the Association, adj
dressed myself to the task of ascertaining,
if possible, the cause Of the "Blght.o A
careful microscopic examination OF fresh
leaves from the vine, revealed the fact, that
the upper surface was peopled by numer-
Gus minute insects, of the order Hemiptera,
sub-order Cicadae. The first examination
showed that they were about the twentieth
of an inch in length, with rudimentary
wings, very active, of a pale, straw color,
eyes large and prominent, and located at
the poslerior portion Of the head, antenee
two jonted near the head, long and slender,
abdomen composedof seven rings, the tibia
armed with seven spines, and the t6oSi ter
minating in two claws. The insect is pro-
yided with a suctorial apparatus, with
which it penetrates the epidermis of the
upper surface Of the leaf, drawing
from the cellular tissue its nourish-
ment. | watched its movements upon
the leaf, with great care, by the aid
Of a magnifying glass, and found, that
after the puncture Of the cuticle of the leaf,
the insect, after filling itself with the sap,
c,a, Il Al
minute globule Of sap would cXude from
the puncturesand although invisible to the
nakedeye, would form, upon becoming dry,
dark circular spot, like those alluded to
in my former report.
The excrementitious deposit OF the insect
presents a grayish white appearance upon
the upper surface of the leai, which is also
their feeding ground but they retire to the
under side for moulting purposes and retire
ment. An examination Of leaves from
several different localities showed the same
result as above stated. At one place found
upon the vines a large number of Ma5etis
Religioso (Prdying Mmtis) which seemed
devouring the cicadae. Carefully prepared
drawings of these insects were presented
to Professor Glover. the able and industri-
GUS entomologist of the agricultural depart
ment for insnection and was nIecsad IN
lelrn that they had not escaped his scru,;-
nizinp search: but / did not understand
from him that he had published anything
regarding their habits, but | understand
they will appear in their proper place in
his great work ON entomology, soon to be
published. Having now discovered, as |
believed, the cause of blight in the leaves,
Cor without a healthy condition of these
The fruit would be deprived of elaborated
san. necessary for the full deyelopement of
the fruit I directed NV attention 10 The
discovery of some means 10 be conveniently
annlied that would destroy the insect with
att ;ni,,rv to The nIant. Having Of hand
bottle of Cook,s BALM Of life I nnnlied if
freely to the surface of n leaf and found
thattbe insects were Immediately DESTROYED
without PRODUCING any iniuriouS effect mon
the tissues of Inc leaf. Knowing that sul-
,,htn in solution constituted nn essential
element in dis preparatjon. I sought for
some vehicle that would hold a sufficient
quantity in solution to accomplish
the desired object. namely. the destruction
of the insect without injury to the leaf ar
fruit.
Herewith are presented two preparations
which are believed to possess the reoni.
site properties. but their value can only be
determined by actual use. SULPHUR is dis
solved with great difficulty. and very spar
inely except in strong alkaline solutions
under great heat and pressure. The solu-
lion marked No. | was obtained bv boil
inc SULPHUR in a saturated solution Of boz
ray. and reducing with water. but this
would be considered too expensive for gen
eraI use. That marked No. was 6re.
pared by shaking lime. one pound. dry)
with two ounces of SULPHUR. and dlutinr
with five gallons of water. | think il viii
bear twenty gallons and be effective. II
should be appiied at night. in the form of
sprav. The value of this or anv other
liuud. can only be determined bv use unnn
an adequate scale. The leaves herewith
presented were. four days since. subjected
to a thorough bath of these prenarations,
by the use of A sponge and the action of
both auneared to be fbe same. ne The in
sects were DESTROYED without iniu,v 70 The
leaf. ~ also exhibit leaves from ihe same
vine in close proximity. which We're not
thus treated, thus showing the contrast.
The season l. now loo far odyoncnd to
annly many practical tests hnt Il il honcd
that another season nav show some yolua-
BILE results from this small bepinninp In
making This applicatiop to leaves undc-