Sacramento daily record-union. [volume] (Sacramento [Calif.]) 1875-1891, 1883-04-28
GRAIN AND FRUIT PESTS.
GRAIN CROPS AND FRUIT ATTACKED III
SOME COUNTIES.
The Newly Discovered Insects Duly TX
plained-Their Habits Given and
the Remedies Necessary.


make inquiries concerning the so-called grain.
bug, which is reported as damaging the wheat
and other cereal crops. and also calling his
attention to an article which appeared in the
San Francisco Bulletin of the 24Eh instant.
After reading the article referred to, Mr..
Cooke stated that he had some specimens of
the insects ihst were forwarded to him from
county south Of San Francisco, and that at
present its appearance was reported from
seven counties. The insects received by him
belong, he said, to the family commonly
called plant-lice (Aphide). and this species
is known to naturaists "a Aphis arena tfso-
ricius) Aphis granaria (KirDs Aphts cereals
(Kalt). Aphis Rordei (Kyberl SegphonophorG
dUene (Fab J.
Reporter-Can you give any explanation as
to the sudden appearance OF The insect
Answer-It may have been in the locali-
ties infested for some time before they at
tracted the attention of the grain. growers.
Besides, they increase very rapidly.
Reptile writer in the Bulletin says he
found the earth around the roots OF barley
grayish color, with the eggs, etc. Do you
think the eggs were deposited SO thickly as to
discolor the ground
A person unacquainted with the nstu-
raj history of the Gphid9 is liable to make
such mistakes.
Rep.-Whst do you refer to by ' making
such mistakes y
A.-The plant-lice are said to be psrtheno-
genisis, term derived from two Greek words
signifying virgin production-ihe produc-
ton Of young by female without union with
male one of the phenomena OF alternate
generation. Also that virgin aphis pro-
duces her young alive, and is, therefore, sc.
cordng to Bonnet, capable of producing ten
generations of her kind, equal to one quin-
tillion in number without the union of
the sexes. He writes; We know
that this reproduction often goes on till the
eleventh generation then this process
ceases-the last generation is of perfect in
sects, with separate sexes, and these produce
ova, which next year become the productive
virgins. - The aphis produces
each year ten lsrvipsrous broods and one
which is oviparous - that is, ten living
broods and one laying of eggs. Professor
Huxley writes " The virgin viviparous
aphis produces its broods of young from I'M
fortified ovan Therefore, you see that it is
hardly possible that ihs discoloration Of the
earth around the roots of barley was caused
by the quantity OF eggs deposited therein. es-
pecislly at this early season.
Rep.-Can you give an idea as to the rapid
ity OF increase Of these insects with any de-
gree of certainty?
Al have stated Bonnet's calculation.
Reaumer has proved that in five generations
one virgin apbis msy be the progenitor of
g. 904 800, 600 descendants. and supposed there
could be twenty generations in one year.
Professor Asa Fitch, of New York, in his
sixth report, writes :" A single one Virgin
aphis) producing four daily. and these becom-
ing equally prolific when they are three days
old, her descendants in twenty days will num-
Der upwards of two millions, and will be in
creasing at the rate of million daily"
Rep.-Have you an opinion as to the
amount of damage growing crops of wheat
and barley are likely to suffer from being in
tested by these plant-lice
Al have read of cases where one-hah of
the crop attacked was destroyed, namely, in
New York State in 1861. Curtis, in his
farm insects of Eogland, writes that it did
less damage to the grain crop, by far. than
the apnis on the pea and bear.
Rep.-Are there any insect parasites that
keep this pest in check, or that is supposed to
do 80?
A.-There are several species of insects
which devour plant lice, VIZ the lady birds
(Coccinelli6 e)-nearly all the species of this
family the Chrysopss golden-eved flies
and common species Of bug-Nabis fera-
and many other species in the larva and per-
feet states live upon plant lice. There are
also several species of Hymenopters that are
parasites on plant lice; also the Syrphus
iarya.
Rep.--Do you think the natural enemies of
the grain aphis can keep them successfully in
check?
A The balance of nature " is a pet
theory with natnralists-i that the foes of an
invading species will ere lopg check It's in
| crease" However, think that under pres
ent circumstances it will be necessary to use
artificial remedies.
Rep.-What remedies would you propose
A.-As soon as the wheat or other crop was
secured, l would burn every stalk of stubble,
grass etc, in or around fields that had been
infested, in this way destroying the ova de.
| posted by the sexual generation, or destroy
ing the virgin sphides remaining On the vege-
tation.
Rep.-Do understand you to say that the
ovs are laid late in the season
Al wilt answer you by quoting from
Professor Fitch, of New York "All the
insects we see in the grain during the spring
and summer are females. These do not pro.
duce eggs, but living young, which mature in
few days, acd ere fertile without any inter.
course of the sexes. 1t is only when cold
weather is coming on, at the end of the sea.
son, that males are produced. The insects
then pair, and the fsmsles thereupon Law
eggs, placing them, no doubt, upon the fall
sown wheat, ETC., which is than up in our
fields" These eggs are Matched as soon az
the warm weather OF spring arrives.
Rep.-Then you think that the insects live
on the leaves OF grain until the head or grain
begins TO form?
Automatically and at that stage of
their existence H. G.. while feeding upon the
leaves) tt cir color is green but as soon as
they begin to feed on the ears of grain thew
assume darker color, and sometimes a vel.
low color.
Rep.-What effect do you think they will
have on the present crop?
Al think many viii find when they have
f ightened than hurt.
Rep.-Well, this is all about the grain
pssts. What are Chs insects on this pesch
branch received from G5idlsy?
At Is the peach sphis, species of the
same tribe as the grain aphis.
Rep.-But the reports from the vicinity Of
Gridiey are that the same pest which ia in
Jurih8 iruis aad fruit trees Is also destroying
the grain in that section.
A.-They think so, from the very close and
almost irdistir guishable resemblance. but
Lney are another species of the same genus.
Inc grain aphis, when examined under a
microscope, will be found to be OF a darlr
brownisn-ereen color, while the peach aphis
Is brownish red, and also has the points bv
which 1t Is distinguished. but which are only
Observable by naturalists So far as knovr
the peach apbis has not been found ON ca.
reals, nor the grain aphis on fruit trees
Rsp.-What remedy could you suggest az
most effective for destroying the peach apbis9
A,-Ine trees should be thoroughly SPRAYED
or orenched with whale oil soap, one pound
to eacn one aud half gallons Of water. or
very strong soapsuds may be used. This viii
os Iound enectiVe If thoroughly applied, and
VIII not lnJure either foliage OF fruit.
II