Report on the Locusts
of the San Joaquin Valley
D.W. Coquillett

ENTOMOLOGY
LIBRARY

.

AGRICULTURAL
LIBRARY,

UNIVERSITY

CALIFORNIA.

REPOKT

ON THE

,OCUSTS OF THE SAN JOAQUIN VALLEY, CAL

BY

D. W. COQUIllLETT.

[Extracted from the Report of the Entomologist, U. S. Department
of Agriculture, for 1885.]

1886.

AUTHOR'S! KDITION.

11 E P 0 R T

ON THE

LOCUSTS OF THE SAN JOAQUIN VALLEY, CAL

BY

D. \V. COQUILLETT.

[Extracted from the Report of the Entomologist, U. 8. Department
of Agriculture, for 18W5.]

1886.

10010 co 1

ENTOMOLOGY
LIBRAE*

REPORT ON THE LOCUSTS OF THE SAN JOAQ.UIN VALLEY, CALI-
FORNIA/

By D. W. COQUILLETT.

ANAHEIM, Los ANGELES COUNTY, CALIFORNIA,

September 1, 1685.

DEAR SIR : I herewith transmit to yon my report upon the Locusts of the San Joa
quin Valley, California.

In accordance with your telegram of the 1st of June, I proceeded to Stockton for the
purpose of interviewing Mr. G. N. Milco, one of the members of the State Horticult-
ural Commission, in order to ascertain from him what part of the San Joaquin Valley
was most infested with locusts. I learned from him that they were about as numerous
in the vicinity of Merced, in Merced County, as in any other part of the valley, and
he invited me to pay a visit to the Bnhach plantation — of which he is part; owner —
which is situated about 6 miles west of the village of Merced, adding that if I found
the locality to be a desirable one I would be perfectly welcome to remain at the plan-
tation for as long a time as 1 desired. A few minutes later I had an interview with
the other proprietor of this plantation, Mr. J. D. Peters, a prominent business man of
Stockton, who, upon learning my mission, also invited me to visit the Buhach planta-
tion and remain there as long as I wished. Accordingly I proceeded at once to the
above plantation, accompanied by Mr. Peters, and finding it to be a very desirable
location — the locusts "being very abundant, and every thing necessary being offered
me for the prosecution of my studies— I concluded to make this plantation niy head-
quarters.

Already the locusts had almost wholly defoliated several collections of trees and
shrubs growing around the residences in this valley, and many alfalfa and grain fields*
literally swarmed with them.

About the middle of June the superintendent of the Bnhach plantation, Mr. G. E_
Ladd, who extended me every facility in his power to aid me in study ing up the locust,
problem in this valley, wrote to the superintendent of the Natoma vineyard, near Fol

*The following letter of instructions will indicate the points upon which informa-
tion was needed :

DEPARTMENT OF AGRICULTURE,

DIVISION OF ENTOMOLOGY,

Washington, D. C., June 1, 1885.

DEAR SIR: In accordance with my telegram and the inclosed commission, I wish
yon to give your time for from six to eight weeks or more, as occasion may require, to
a thorough examination of the Locust troubles in California. You are doubtless fa-
miliar with the work of the United States Entomological Commission on Caloptenus
vpretus, and of course it will not be necessary that yon repeat descriptions of any of
the remedies there given in detail or illustrated. I wish information as to the amount
of damage; as to the range; as to the source and movements both of the young and
tin- winged ; the kinds of soil in which they are hatched most abundantly, and every-
thing pertaining to their natural history, which will ot course be found very similar to
that of Npreliin. Accounts, as far as possible with illustrations, of all partieular meas-
ures adopted that an- different from those adopted in the, East; observations on enemies
and parasites, and, in fact, as full a statement of the whole subject as will permit you
to make a satisfactory report, to be published by the Department.

You should send on specimens properly preserved of the insect in its different stages,
together with egg-pods, and particularly all parasites and other enemies fonnr7. attack-
ing it. * * *

Yours very truly,

C. V. RILEY,

Entomologist.

D. W. COQUILLETT, 272681

Anaheim, Cat.

3

eoni, in Sacramento County, asking him what remedies he had used for destroying the
locusts, and also what success he had had with them, and received a reply stating that
he had been experimenting with a mixture composed of arsenic, sugar, middlings, and
water, and was of the opinion that this would prove a decided success.

About this time Messrs. George West and Thomas Mint-urn, two of the proprietors of
the extensive orchard and vineyard of Kohler, West <fc Minturn, at Minturu Station,
in Fresno County, pafd a visit to the Natoma vineyard for the purpose of learning more
about the above remedy, and were so much pleased wich what they saw of its effects
upon the locusts that they determined to try it upon their own orchard and vineyard
at Minturn Station, and invited Mr. Ladd and myself to visit them and witness the
results of the experiments. Accordingly, on the 24th of June, we proceeded to Mill-
turn Station, and from what we there saw of the effects of this remedy, were con-
vinced that it was a decided success.

About the 12th of July, Messrs. Milco & Peters sent to the Buhach plantation 1,000
pounds of arsenic, an equal quantity of sugar, and about 3 tons of bran, to be used in
poisoning the locusts upon about 300 acres of the plantation that was plained out to
fruit trees and grape-vines. Bran has been substituted for the middlings, not only
on account of its being cheaper, but also from the fact that in drying after having
been wet, it forms a jagged mass, which otters the locusts a chance to feed upon it;
whereas middlings, in drying, being much finer than bran, forms a smooth, even
mass, which gives the locusts no chance to get a bite of it. During the next two days
about two- fifths of the above materials were mixed and put out upon the 300 acres
mentioned above, and this was repeated about one week later. After the expiration
of a week after this second batch had been put out there were at least 400 dead locusts
to every living one.

I remained at the Buhach plantation until the first wreek in August, when, in ac-
cordance with your request for me to return to niy home and write my report, I took
the train for Anaheim on the «th of August, arid arrived at my destination the next
day. A few days before this I paid a visit to Messrs. Milco & Peters, at Stockton,
but could not prevail upon them to receive any compeusalion whateverfor my board,
&c., while at their plantation. During my stay at the plantation these gentlemen
did all in their power to aid me in my studies, and Mr. Milco visited the plantation
several times while I was staying Jjhere, and assisted me much.

To both of these gentlemen, and also to Mr. Ladd, the superintendent, my warmest
thanks are due. To Dr. P. R. Uhler I am indebted for the determination of several
species of locusts ; and last, but by no means least, I am especially indebted to your-
self for determinations and other help.
Respectfully yours,

D. W. COQUILLETT.

Prof. C. V. RILEY,

V. S. Entomologist.

The following pages comprise a report of iny observations upon the
locusts of the San Joaquiu Valley, California, during the months of June
and July, 1885.

I was located at the Buhach plantation, which is situated about 6
miles west of the village of Merced, in Merced County. This plantation
consists of about 400 acres, the greater part of \\hich is planted out to
fruit trees and grape-vines. It is situated in the midst of a great grain-
growing region, and on every side of it grain fields stretch away almost
as far as the eye can reach, dotted here and there by the residences of
the grain growers or of their tenants, and by the fruit and ornamental
trees which usually surround these residences.

When I arrived at this plantation early in the month of June, the
locusts were already in possession, but they were chiefly found in the
vicinity of the Lornbardy poplar trees which grew along the banks of
almost" every irrigating ditch upon the plantation. Already many of
these trees were beginning to show evidences of the work of the locusts,
the leaves presenting the appearance of having been riddled by hail-
stones. Many of the grape-vines growing next to these trees were also
infested by locusts, which had not only stripped many of them of their
leaves, but had also gnawed off the buds and tender bark.

The locusts were confined to the trees and grape-vines growing along

the outer edges of the orchards and vineyards, but later in the season
they gradually spread all over the plantation. They seemed to prefer
the leaves of poplar trees and grape-vines to any others, and were espe-
cially fond of the tender bark of grape-vines. While they would eat
the leaves of almost every kind of tree, shrub, and plant growing* upon
the plantation, yet they manifested an evident preference for certain
kinds. The leaves of peach trees were not much relished by them, but
the fruit was eagerly eaten, and upon bearing peach trees that had been
much infested by the locusts it was no uncommon sight to see nothing
but the leaves and naked pits remaining. Fig and pomegranate trees
suffered but little from their attack, as did also gum and evergreen
trees. I saw a small, barrel-shaped cactus which had its inside eaten
out by the locusts. H

Plants covered with sacking did not escape the attacks of the locusts,
which gnawed holes into the sacking and then entered and devoured
the leaves of the inclosed plant. One lady sought to save a favorite
plant by turning a washtub over it, but upon removing the tub a few
days later she found that the leaves had been entirety stripped from the
plant.

Fields of alfalfa suffered very severely from the attack of the locusts ;
the latter were also very destructive to beans, cabbage, and tomatoes,
but corn, melon, and pumpkin vines were not much injured by them.

The pyrethrum plants — from the flowers of which the insect powder
known as " Buhach" is produced — were not much injured by the locusts.
In places where the plants had been considerably eaten I found many
locusts which acted very much as those do that have been sprayed with
a solution of buhach and water ; they had completely lost the use of
their legs and were lying upon the ground in a very helpless condition,
occasionally jerking a leg or moving a foot. Several of them were dead,
evidently having partaken too freely of the leaves of the pyrethrum
plants, as no poison had been put out up to this time.

Wheat fields, as a rule, were but little injured by the locusts, the
principal injury being done by biting off' a small proportion of the heads
and allowing them to fall upon the ground. Late-sown wheat suffered
the most, and several fields were injured to such an extent that they
were not harvested.

Eye fields were generally much injured by the locusts, which devoured
the exposed kernels in the heads ; I have examined many heads of rye
in which every kernel had been devoured. Mr. D. W. Swain estimated
that he had lost fully one third of his crop of rye on COO acres through
the attacks of locusts. The reason that they were more destructive to
rye than to either wheat or barley is to be found in the fact that the
kernels of wheat and barley are wholly inclosed in a husk, whereas the
kernels of rye are exposed to view.

SPECIES OF LOCUSTS MOST DESTRUCTIVE.

I captured in the San Joaquin Valley no less than twenty different
species of locusts belonging to the subfamilies Acridinct' and (Edipodince,
but the principal damage was committed by four species, three of which
belonged to the Acridincv or Spine- breasted Locusts.

The species which appeared in the greatest numbers was the Devas-
tating Locust (Melanoplus devastator Scudder), which outnumbered all
of the other species combined, in the proportion of at least seven to one.
It was accompanied by the Ash colored Locust (Melanoplus cinereus

Scudder) which was about one-twentieth as abundant as the former
species. These two species were the ones that were the most destructive
to the larger fruit and ornamental trees, and they are the only ones
that I saw feeding upon the ripe kernels of rye in the fields.

During the hottest part of the day they would sometimes take to their
wings and fly to a distance of from 50 to 100 yards at a time. All of
them would not start up at once, but one would start up here, another
there, and so on, each apparently going entirely independent of the
others. When the weather was perfectly calm they would fly in every
direction, but Whenever there was a gentle breeze blowing they would
fly against it ; they would not attempt to fly when the wind was blow-
ing hard.

Sometimes when there was a perfect calm one would start up and fly
a short distance, when, the breeze* tarting up, he would turn and fly
against it ; but when it would begin to blow quite hard he would again
turn about and fly with the wind for a short distance and then alight.

In these migrations, if one of the locusts were to fly against a tall
tree he would alight there and remain for some time, but if he missed
the tree he would continue his flight sometimes until lost to view; at
other times he would gradually approach the earth and finally alight,
either upon the bare earth or upon any plant, shrub, tree, or other ob-
ject that chanced to be in his way.

These locusts do not seem to be able to fly in any direction that they
may choose, nor to alight in any particular place, alighting as often in
the water or upon the bare ground as upon plants. In migrating from
the fields to a collection of trees of any kind a very few of them will
alight in the trees, but the greater number will drop upon the ground
and afterward crawl to a tree and ascend its trunk.

The Ash-colored Locust (M, cinereus) flies with greater ease than the
Devastating Locust (M. devastator). Both species fly in a nearly straight
line, and at a distance ranging all the way from '5 to 20 feet from the
ground.

These migrations were not alwa\s performed for the purpose of ob-
taining food, as I have frequently seen the locusts start out of poplar
trees that as yet had not been much injured by them, of the leaves of
which they are very fond. I have also seen them fly out of wheat-fields
that had not as yet been harvested, and out of low, waste places that
were covered with a rank growth of green weeds.

WHERE DID THESE LOOUSTS HATCH?

As the wind in the San Joaquiu valley during the summer season
usually blows from the southwest, so the course of the locusts would,
in most cases, be directed to the southwest, since they invariably fly
against the wind.

Several persons who had visited the foot-hills lying on the east side
of this valley early in the season stated to me that the locusts were
much more abundant there than they have been in the valley, and that
they appeared there much earlier in the season than they did in the
valley. These persons were nearly always of the opinion that the
locusts which devastated the valley hatched out in the foot-hills, and
that as soon as the feed on the foot-hills began to fail, the locusts mi-
grated to the valley; but I arrived too late in the season to definitely
settle this question, as the locusts were already very numerous in the
valley when I arrived there early in June. I am strongly of the opin-
ion: however, that the greater number of the locusts which appeared

iii this valley the present season were produced from eggs that had
been deposited here during the preceding autumn.

As above stated, when 1 arrived at the Buhach plantation the locusts
were most abundant along the outer edges of the orchards and vine-
yards, while the more central parts were almost wholly free from them.
Now, if the locusts had migrated to this plantation, would they not
have been found as often in the center of the orchards and vineyards
as along the outer edges? But if the locusts had hatched out upon the
plantation we should expect to find them the most numerous in the vi-
cinity of uncultivated land, where the eggs would not have been dis-
turbed by the plow and cultivator ; and this was exactly the situation
where they were fche most numerous — in the vicinity of the uncultivated
land along the outer edges of the orchards and vineyards. Had the
eggs been deposited last autumn in the more central parts of the or-
chards and vineyards, the subsequent cultivating of these would have
destroyed the eggs, so that no locusts would have hatched out in such
situations; and none were found there.

Moreover, I found upon the uncultivated land referred to above quite
a number of young locusts, which were evidently the young of the De-
vastating Locust (M. devastator), since, in their markings, they approach
that species more closely than they do any other of the Spine-breasted
Locusts which inhabit the San Joaquin Valley. The following is a de-
scription of these young locusts, drawn from fresh specimens:

\ lend, ashen-gray, whitish below each eye. Thorax, ashen-brown ; two dark-brown-
ish subdorsal stripes, one on each side, and below each is a whitish line, then a dark
spot bordered below by a whitish line. Abdomen, ashen-pink, mottled with dark
brown. Venter, whitish, unmarked. Legs, ashen-yellow ; hind femora with a longi-
tudinal black stripe on the onter side, interrupted at the middle of the femur and sub-
interrupted at the first one- fourth; upper side of hind femora marked with three*
black spots, the first at one-fifth, the second at two-fifths, and the third at two-thirds
the length of each hind femur from its base, the first spot sometimes wanting, the
second and third spots extending slightly upon the inner side of each hind femur
before the tip. There is a blunt spine between the front legs.

In all of these characters the agreement with the adult Devastating
Locust is very close. There are only three species of Spine breasted
Locusts inhabiting the San Joaquin Valley which approach this species
very closely in their markings; and from each of these both the adult
Devastating Locust and the young locusts above described differ as
follows :

Melanoplus cinereus Scudder (the Ash-colored Locust), has no black
spots on the hind femora.

Melanoplus sp. (probably only a variety of devastator) has no distinct
black subdorsal stripes on the thorax.

Parooct/a sp. (near atlantica Scudd.) has the subdorsal stripes of the
thorax well defined, not interrupted, and of nearly the same width
throughout their entire length, while in the adult Devastating Locust
and the young ones above described these stripes taper posteriorly, are
not well defined, and are generally interrupted.

These young ones quite closely resemble those of the Differential Lo-
cust (Caloptenus differ entialis Thomas), but differ in having no black
dots on the groove on the under side of each hind femur.

It seems quite evident, therefore, that the young locusts above de
cribed are those of the Devastating Locust, the species which committed
the most extensive depredations in the San Joaquiii Valley the present
season ; and if they were the young of that species, then the latter
breeds in the San Joaquiu Valley, since it would have been quite im-
possible for these young ones — many of which were not more than one-

8

fourth grown — to have fotiud their wny to the Buhach plantation from
the foot-hills, M distance of from 15 to 20 miles.

When I first arrived in the valley, the Devastating and Ash-colored
Locusts were most numerous in those grain fields that had not been
plowed for a year or more, that is, in fields of what is commonly called
"volunteer" grain, i. e., self-seeded. Some of the locusts remained in
these fields for two weeks after the grain had been harvested ; by the
latter part of July scarcely a single specimen of either the Devastating
Locust or the Ash-colored Locust could be found in these fields, but the
low waste places, which were quite numerous in and near all of the grain
fields, and which were covered with a rank growth of green weeds, were
infested with immense numbers of these locusts, which doubtless will
breed in these situations.

These waste places are covered with water during the latter part of
the winter season, and sometimes until late in the summer. When the
proper time for putting in the seed arrives they are too wet to be plowed
and seeded, and are therefore allowed to remain undisturbed from year
to year. The green weeds which these waste places contain late in the
season, when the surrounding fields contain nothing green, furnish food
to the locusts until their egg- laying season arrive?, when they will doubt-
less deposit their eggs in these waste places; and as these eggs do not
hatch until the following spring, they must be covered with water for a
period of two or three months. This would not necessarily destroy their
vitality unless they were covered by the water for too long a time, since
Professor Eiley has ascertained that the eggs of the Eocky Mountain
Locust (Galoptenus spretus, Uhler) were not affected by being submerged
in water for three months during the winter and early spring.*

I

CAUSE OF THE ABUNDANCE OF THE DEVASTATING LOCUST IN THE
SAN JOAQUIN VALLEY DURING THE SUMMER OF 1885.

If, as we have supposed above and have every reason to believe to be
a fact, the Devastating Locusts deposit their eggs in these waste places,
we see that in ordinary seasons these locusts will not appear in suffi-
cient numbers to attract attention, since the water will be removed, by
evaporation or otherwise, from the more elevated portions of these
waste places first, and therefore the eggs which have been deposited
in those elevated places will be the first to hatch out, followed by those
that had been deposited in less elevated places, and so on. It follows
that those hatched out the earliest will be the first to acquire wings and
migrate to the adjacent fields, followed after a certain time by those
hatched out next, and so on. By coming into the fields so gradually
and spreading over so large an area of land, their presence will scarcely
be noticed. It is also quite certain that many of the eggs are destroyed
by being too long covered by the water, since, in ordinary seasons, sev-
eral of these waste places contain water until quite late in the summer.
Thus it happens that in ordinary seasons the locusts never appear in
sufficient numbers to attract attention.

. Last winter, however, but little rain fell, and, as a natural conse-
quence, what little water was collected in the waste places soon evap:
orated, leaving these places perfectly dry for some time before the time
for the locust eggs to hatch out had arrived; consequently, when the
time for these eggs to hatch out did arrive, they all hatched out within
a short time of each other, and as they would ail acquire wings and mi-

* See the First Annual Report of the U. S. Entomological Commission, pp. 359, 360.

grate to the adjacent fields nearly at the same time, their coming all at
once, or within a short time of each other, would very naturally attract
attention. Moreover, it is very evident that they appeared in greater
numbers the present season than they do in ordinary seasons, since none
of their eggs were destroyed by being covered with water for too long
a time.

As stated above, the locusts left the grain fields this season a few
weeks after the latter had been harvested, there being no green food
for them to obtain in these fields ; but it is quite probable that, as last
season was a veiy wet one, there may have been green weeds in the
grain fields as late in the season as the locusts deposit their eggs, and
if such was in reality the case, then we may suppose that many of the
locusts deposited their eggs in the fields last autumn. This would ac-
count for the fact that the locusts were most numerous the present
season on those fields which had not been plowed for over one year.

From the above facts it would appear that whenever there is a very
dry winter and spring in the San Joaquin Valley there will be an abun-
dance of locust's in that valley during the following summer ; but when
there is an abundance of rain during the winter and spring months
there will not be an unusual number of locusts during the following
summer.

In the latter part of July I saw several pairs of the Ash-colored Locust
(M. cinereus] united in coition, but up to the time that I left this valley —
the first week in August — I did not see a single pair of the Devastating
Locust thus united.

THE DIFFERENTIAL LOCUST.

The Differential Locust (Caloptenux differ entiaUx Thomas) was only
about one twenty-fifth as numerous as the Devastating Locust. These
two species and the Ash colored Locust were the only Spine breasted
Locusts that appeared in destructive numbers in the San Joaquin Valley
the present season. The only other species of Spine breasted Locusts
that I took in that valley are the Acridium shoshone Thomas ^ the Hes-
perolettix viridis (Thomas), and the Paroxya (near atlantica Sc.).

When I first came to this valley, early in June, the Differential Locust
was mostly in the wingless state, there being only about one winged speci-
men to ten wingless ones ; by the last week in July the greater number
of them had acquired wings. On the 23d of June I saw the first pair
united in coition, but the majority of them did not pair until about three
weeks later. After coition, and before the eggs are deposited, the
abdomen of the female increases very much in size.

The first egg-mass which I saw this species deposit was deposited on
the 23d of July. The location chosen was a shaded place on the north
side of a row of trees and in a sandy soil. A basin-like hole had been
dug in the ground at the base of an ornamental tree, and had been filled
with water a day or so previously, for the purpose of irrigating the tree.
The female locust had worked her abdomen into the ground on the
outer edge of this basin. I first discovered her in this position at about
3 o'clock in the afternoon, and at 15 minutes past 4 o'clock she had com-
pleted depositing an egg-mass and walked away.

This egg mass is about three -fourths of an inch long, slightly curved,
and a little less in diameter than an ordinary lead pencil. The space
between the uppermost eggs and the surface of the surrounding earth
was filled in with a frothy matter. When freshly deposited the egg-
mass is of a pale bluish color.

10
•

On several succeeding days I saw many females of this species deposit
their eggs, and in nearly every instance the situation chosen for this
purpose was the edge of one of the basin-like hollows at the base of a
tree.

I saw several of the females make numerous attempts to sink their
abdomens into the earth upon a hard beaten walk, but always without
meeting with success. They do not appear to have the power to pene-
trate hard substances that is possessed by some locusts. Upon one oc-
casion I saw a female Chloealtis conspersa (Harris), that had excavated
a hole in the bark of a burr-oak log by means of the horny plates at the
tip of her abdomen ; when found by me she had reached a depth equal to
about one-half the length of her abdomen. This occurred in Northern
Illinois.

The Differential Locust is not so easily startled as the Devastating
Locust is, and its flight is heavier and sustained for only a short distance,
seldom flying more than 12 or 14 feet at a time. It does not perform
those migrations indulged in by the Devastating and Ash-colored Lo-
custs, seldom taking to its wings except when disturbed.

It was principally found in trees, being especially partial to the leaves
of poplar trees. I did not find it in the grain fields, and it occurred
only in limited numbers in the low, -waste places, overgrown with weeds.
It was very numerous in alfalfa fields, where it probably breeds, as young
ones of all sizes were very numerous in these fields.

THE YELLOW LOCUST.

The only species of Spineless-breasted Locusts (QVdipodince) that ap-
peared in destructive numbers in the San Joaquin Valley the present
season was the Yellow Locust (Trimerotropis pxeudofasciata Scudder),
which was only about one-twentieth as abundant as the Devastating
Locust. When I first came to the valley early in June, this species was
most numerous in grain fields, but after these had been harvested it
migrated to new pastures. In many places it was very destructive to
the leaves of grape-vines and low trees, but it was very seldom found
in large trees.

The flight of the Yellow Locust is more undulating than that of the
Devastating Locust, and is sometimes continued for long distances at a
time. They do not always fly in one direction, against the wind, as the
last-named species almost invariably does, but fly in almost every direc-
tion. They do not all start at once, but one will start up here, another
there, and so on, each apparently going entirely independent of the
others.

Their flight is sometimes accompanied by a crackling sound, but they
appear to produce this sound at their pleasure while on the wing. Sev-
eral other species of Spineless-breasted Locusts ((Edipodincv) can also
produce this sound while on the wing, but I am not acquainted with a
single species of Spine breasted Locust (Acridince) that ever produces a
similar sound.

The Yellow Locusts are more frequently found resting upon the bare
ground than in any other situation, but during the hottest part of the
day they seek the shade of low weeds, grape-vines, small trees, &c.,
which they usually ascend, but never, or very seldom, go very high. I
have frequently seen them feed upon dry leaves, and they seem to pre-
fer feeding upon these on the ground to climbing after the green ones.

I have also seen them feed upon a locust that had but recently died;
they would usually begin upon the side of the thorax nextto the head,

11

and eat away the whole side and internal parts of the thorax, sometimes
also devouring the greater part of the abdomen. This cannibalistic
habit seems to be indulged in by all the different species of locusts that
inhabit this valley.

1 saw several pairs of Yellow Locusts united in coition in the latter
part of June, but did not succeed in obtaining any eggs, although I fre-
quently saw a female that had her abdomen sunken its whole length
into the loose sand in the grain fields; after she had withdrawn her
abdomen and walked away, 1 carefully dug up the earth in the place
where her abdomen had been thrust into the sand, but uev-er succeeded
in obtaining the eggs. As the situation chosen by these females was
in the open fields where it was impossible to watch their movements
unobserved by them, it is quite likely that my presence frightened or
otherwise disturbed them to such an extent that they would not deposit
their eggs so long as I was within view of them. So long as I remained
hidden from view, the female Differential Locust would continue deposit-
ing her eggs, that is, wheii I discovered her in the act of depositing
eggs some distance off, and my presence was unknown to her; but, when
I came upon her unawares and she saw me, it mattered not how quickly
and carefully I withdrew myself from her sight, she always refused to
deposit any eggs, after a certain time withdrawing her abdomen and
walking away. Hence 1 believe that no female locust will deposit her
eggs when she is aware of the presence of any person.

OTHER SPECIES OF LOCUSTS.

I captured eighteen different species of locusts in the San Joaquiii
Valley during the two months that I remained in that valley. In order
to show the comparative abundance of each of these species, I sub-
join herewith a list of those determined, with numbers attached show-
ing the numbers in which the locusts of each species appeared as com-
pared with those of any of the other species. Thus, the first species is
represented by the number 1 and the second species by the number 4,
indicating that there were four specimens of the latter species to every
one of the former, and so on throughout the list:

Pxoloessa tejcana Scudder

Hesperotetlix viridis Thomas 4

Cotiozoa wallula Scudder 6

Camnula pellHcida S<mdder &

Acridium shoshom Thomas 10

DixHoxleira ren nst<i St:ll 10

Trimcrotrojtix rinciildta Scudder 5iO

Trimerotropix sp. ? 40

Trimerotropis sp. '{ 50

Melanoplus probable var. of devastator -r>0

Paroxya near atlantica 50

Trimerotropi* up. I 75

Diswsteira upnrcala Saussure 100

Caloptenns difftrentittlis Thomas 750

Melano^lu-H cinereus Scudder 1, 000

Trinitrotrofjix pseudofazciata Scndder 1 , 000

Melanoplus devastator Scudder ^0, U< 0

INJURY COMMITTED BY THE LOCUSTS.

It is very difficult to give any idea of the injury committed by the
locusts in the San Joaquin Valley the present season. A majority of
the trees and grape-vines that had been defoliated by them, put forth
a new growth of leaves in the course of three or four weeks from the

12

buds that ordinarily would not have developed until the following sea-
son; in these cases the only injury sustained through the attacks of the
locusts was a partial arrest of the growth of the trees and vines, and
in many cases a loss of the fruit upon fruit-trees and grape-vines in
bearing.

Grape-vines that had been stripped of their leaves, buds, and much
of their bark, sent out new shoots from the base of the vines, the de-
nuded part dying back as far as the buds arid bark had been removed.
In cases where the bark had been removed but the buds had not been
injured, these buds developed a new set of leaves, and a new bark
seemed to be forming in those places where the old bark had been re-
moved.

Several vineyardists plowed under their young vines to save them
from receiving further injury from the attacks of the locusts, and also
to prevent them from drying out, and the majority of the vines treated
in this manner, in the course of three or four weeks, sent up a new
growth through the thin covering of earth that had been thrown upon
them by the plow.

The devastations committed by the locusts in the grain fields and
vegetable gardens were in most cases irreparable. Alfalfa fields were
in most cases kept eaten down so closely by the locusts that not a sin-
gle crop of hay was gathered from them.

NATURAL ENEMIES.

Besides several kinds of domestic animals, such as hogs, dogs, cats,
chickens, ducks, turkeys, &c., I have also seen several kinds of wild ani-
mals, birds, and insects prey ing upon the locusts. Among these is a large,
ground lizard, or swift, as it is commonly called, which I have twice
seen catch a locust in its mouth, springing upon it somewhat as a cat
would spring upon a mouse. I have also seen the following birds feed-
ing upon locusts: Bullock's oriole (Icterus bullockii), a sparrow resem-
bling the Eastern Song sparrow (Melospiza melodia), and a larger spar-
row having a patch of red feathers on the head.

Among insects I saw two different species of wasps preying upon the
locusts. The most common species is the Priononyx atrata. When a
locust takes to its wings one of these wasps will pounce upon it, seize
it in her legs and bear it to the ground, after which she thrusts her
sting into it; the part of the locust into which the sting is thrust is the
under side of the thorax, between the insertion of the first two pairs of
legs. Soon after being stung the Locust becomes motionless, when the
wasp gets astride of it, seizes its an tenure with her jaws, and drags the
locust to her burrow, the body of the locust being under and directed
in the same direction as that of its captor, three of the wasp's legs be-
ing on one side of the locust and three on the other. The wasp leaves
the locust at short intervals for the purpose of finding her burrow, after
which she returns to it again and drags it a short distance farther in
the direction of her burrow.

I have seen upwards of two dozen of these wasps thus dragging lo-
custs to their burrows, which are always made in loose, sandy soil, and
in every instance the victim was a Devastating Locust. How and why
they always select this species for their victims is a mystery, since there
were always three or four other species of locusts of the same size and
nearly of the same color — among which may be mentioned the Ash-
colored Locust — always associated with them; still I never saw them
attacking any other species than the Devastating Locust.

After dragging the locust into her burrow the wasp stations herself

13

in front of the latter, her head directed from it, and then with her front
feet she throws the dirt into her burrow, occasionally going into the lat-
ter apparently for the purpose of scratching the dirt into the farthest
end of it, soon to return and resume the tilling-up process ; in this way
she continues until the burrow is tilled up and not a trace of its existence
is to be seen.

In digging her burrow the wasp frequently uses her strong jaws, but
in tilling it up she uses her feet almost altogether, standing upon her
two hind pairs of feet and scratching with her front ones somewhat as
a dog would ; all of her movements are very rapid.

I saw a single specimen of another species of wasp dragging a De-
vastating Locust to her burrow ^ she dragged the locust into her burrow
in the same manner that the Priononyx atrata did, as described above.

I also saw a single specimen of the 8phex rufiventris dragging a wing-
less cricket (Anabrus sp.) to her burrow in a similar manner. During
the fore part of July I saw several pairs of these tfphex wasps united
in coition in the dooryardof the Buhach plantation, while many of them
were lying upon the ground dead ; these latter I judged were males
which had died after coition had taken place.

On the 20th of July I found three red mites attached to the underside
of the breast of a Trimerotropis sp., a Spineless-breasted Locust having
the hind wings bluish at the base. These mites were in shape like an
inverted tea cup, and were doubtless the young Trombidium locustarum ;
but unfortunately they escaped before a careful examination of them
could be made, and I did not succeed in obtaining any additional speci-
mens.

On the Gthof July a dipterous larva, about 9 millimeters long, issued
from an oval hole in the side of the thorax next the head of a Disso-
steira spurcata which I had inclosed in my cyanide bottle ; this larva
died before pupating, having been killed by the cyanide, as it was not
discovered by me until an hour or more had elapsed after I placed the
locust in the bottle.

This was the only specimen of this parasite that I obtained, although
I dissected many hundred locusts in search of additional specimens,
but without meeting with success.

In a paper on the North American Conopidce, which appeared in the
Transactions of the Connecticut Academy of Natural Sciences, for the
month of March, 1885 (vol. vi, p. 889), Dr. S. W. Willistou, quoting
from Brauer, states that Conopa is sometimes parasitic upon (Edlp(tda
(a genus of Spineless-breasted Locusts). The only species ot Conops
that I have taken in the San Joaquin Valley is the Physocephala affmis,
Williston ; and the Dipterous larva mentioned above may have belonged
to this species.

REMEDIES.

As soon as the locusts began to appear in destructive numbers upon
the Buhach plantation, the superintendent, Mr. G-. E. Ladd, tried a great
many means of destroying them.

Adjoining this plantation on the west is an alfalfa field that literally
swarmed with locusts; many of them found their way to the adjacent
trees upon the Buhach plantation, and to intercept them Mr. Ladd
placed a windrow of dry pyrethrum steins between this alfalfa tield and
the nearest row of trees upon the plantation. In the evening many of
the locusts would crawl into this windrow for the purpose of spending
the night therein, and late at night the windrow was set on fire j in this

14

way a great many of the locusts were destroyed, but a great many more
passed over the windrow into the adjacent trees.

This alfalfa field was rolled late in the evening with a heavy wooden
roller, but this did not kill very many of the locusts, although the
ground was quite level, but sandy. I have repeatedly stepped squarely
upon a locust on loose, sandy soil, without injuring the locust in the
slightest degree, so far as I could discover.

A small patch of alfalfa that was thickly infested with locusts was
sprayed with a solution composed of 1 part of the kerosene emulsion (2
gallons kerosene, 1 gallon water, and on^-half pound of soap) diluted
with 4 parts of water, but the locusts were not killed by it. Locusts
immersed in the undiluted emulsion died a few minutes afterwards.

Mr. G. N. Milco, one of the proprietors of the Buhach plantation, tried
the experiment of driving the locusts out of a small vegetable garden by
burning some flowers of sulphur on the windward side of the garden, but
the locusts were not visibly affected by it. Several other persons also
tried this remedy, but always with a like result.

This remedy might prove effectual in localities where the air is so
damp and heavy as to keep the smoke near the ground, but in a climate
where the air is so light as it is in the San Joaquiu Valley in the sum-
mer time it will avail nothing, as the smoke rises rapidly in the air and
thus is not brought in contact with the locusts upon the surrounding
vegetation.

>.r. Frank Smith, whose farm adjoins the Buhach plantation on the
west, had a trough of zinc constructed, the dimensions of which were
about as follows: Length, 6 feet; width, 2 feet ; depth, 18 inches. This
was mounted on runners, and late in the evening it was drawn by a
horse through the orchard; the bottom of the trough was covered to the
depth of 5 or 6 inches with strong soap-suds.

In operating it, the trough was drawn beneath a tree infested with
locusts ; the tree was then struck with a heavy stick that had been
wrapped in several thicknesses of cloth to prevent bruising the tree ;.
by this operation many of the locusts were dislodged from the tree and
fell into the soap-suds in the trough, and after a certain quantity of
them had been thus collected they were transferred into grain-sacks and
afterwards beaten to death with a heavy club. In this manner a great
many of the locusts were destroyed.

This plan would have been more effectual had there been two troughs
instead of only one, so that there could have been a trough placed on
each side of the tree. The best results were obtained when it was
operated very late at night, when the locusts were somewhat stupefied
by the cold.

A remedy that has been very successful in destroying locusts consists
of a certain proportion of bran, arsenic, sugar, and water; these have
been used in different proportions, but the one that appears to give the
best results consists of 1 part by weight of arsenic, 1 of sugar, and 6 of
bran, to which is added a sufficient quantity of water to make a wet
mash.

This preparation is usually prepared in wash tubs or half-barrels.
One of these is filled about three fourths full of dry bran, and to this is
added about 5 pounds of arsenic, which is thoroughly stirred through
the bran with a spade or shovel. Five pounds of sugar is next thrown
into a pail, which is then filled with water and the sugar stirred until
it is dissolved, when this sugar- water is added to the bran and arsenic
and the three well stirred; more water is added and the stirring con-
tinued until every portion of the mash becomes thoroughly saturated.

15

About a teaspoonfnl of this mash is placed at the root of each tree,
shrub, or plant infested with locusts, dropping it in the shade when this
can be done. In the case of low shrubs or plants nothing more need be
done, as the locusts will find their way to the poison, but when large
trees are treated the locusts should be jarred out of them, or be driven
out with long poles.

I have known locusts to be killed by eating some of this mash that
had been put out over a week previously. The poison works very slowly,
and when put out early in the morning will show but little effect upon
the locusts until quite late in the day. A Devastating Locust that I
saw eating the mash at 9 o'clock in the forenoon was still alive at 6 in
the evening, but was dead when next examined early the next morning.

Allowing a teaspoon fill of this mash to each grape vine in the vine-
yard— the vines being 7 or 8 feet apart — this will require about 10
pounds of the dry bran (and arsenic and sugar in proportion) to each
acre. The cost of the material will vary, but should not exceed 50 cents
for each acre of grape-vines, including cost of labor for mixing and ap-
plying it. For orchards the cost will be much less than this.

The addition of sugar to this mash is merely for the purpose of caus-
ing the arsenic to adhere to the particles of bran, and not for the pur-
pose of increasing its attractiveness, since bran is more attractive to the
locusts than sugar. This I have demonstrated to my own satisfaction.
A quantity of sugar was placed upon the ground contiguous to an equal
quantity of bran mash ; when a locust came to the sugar he would eat a
little of it, move on a short distance and again take a few bites of the
sugar, and continue in this manner until he reached the mash, when he
would settle down, eat his fill, and tben move off. The locusts which
came to the mash before reaching the sugar would, almost without ex-
ception, eat their fill of the inash and then walk away, but occasionally
one would leave the mash and take a lew bites of the sugar, only to re-
turn to the mash again. None of them ate their till of the sugar, but
always manifested an evident preference for the mash.

This mash was used upon about 300 acres of orchard and vineyard on
the Buhach plantation, and about two weeks later scarcely a living
locust was to be seen where they could have been counted by the hun-
dred or even thousands before the poison had been applied, the ground
in many places being literally covered with the dead bodies of the slain.

Several other parties also used this poisonous mash, and so far as I
was able to learn, it gave entire satisfaction in every instance.

By exercising only ordinary precautions there need be no fear of en-
dangering the lives of either man or any of the domestic animals in using
this poisonous preparation. It should be mixed in a close room to pre-
vent the arsenic from being blown about by the wind. There is no need
of touching the arsenic or the mixture with the hands, as the mixing
and distributing is accomplished by means of spades, shovels, wooden
paddles, &c.

Of course this mixture should not be put out in places where poultry
or any of the domestic animals can gain access to it. Upon the Buhach
plantation were four greyhounds and several cats that were allowed to
roam about the plantation where this mixture had been put out for the
locusts: still at the time that I left the plantation — about four weeks
after the poisonous mixture had been put out — not one of them had
been killed either by eating of the mixture itself, or of the locusts that
had been poisoned by it.

There were also several barnyard fowls upon this plantation, but not
one of them was poisoned from having eaten locusts that may have

16

found their way to the poultry range after having eaten of the poison-
ous mixture. Mr. Boynton, whose farm adjoins the Buhach plantation
on the west, stated to me that many of the locusts which had eaten of
the poisonous mixture would fall into an irrigating ditch that flowed
through his poultry yard, and many of the locusts were thus carried
within the reach of his fowls; still he was not aware that any of the lat-
ter had died from the effects of having eaten of the poisoned locusts.

In fact, I did not learn of a single instance where this mixture had
caused the death of any person, nor of any domestic animal, although
it was used very extensively in many parts of the San Joaquiu Valley.
Neither were the birds killed in any considerable numbers from hav-
ing eaten either of the mixture itself or of the locusts that had been
poisoned by it. During the four weeks following the putting out of
this mixture upon about 300 acres of the Buhach plantation, I found
only about half a dozen dead birds that had evidently met their death
through the agency of this mixture ; these consisted of three or four
meadow larks, a bee-bird, and a field sparrow.

Rabbits and hares, or " jack rabbits," as they are commonly called,
were destroyed in large numbers by this mixture. After the greater
numbers of locusts upon the Buhach plantation toad been destroyed the
work of extermination was carried into a large patch of wild sunflowers
adjoining the plantation on the north, and as one of the results, at least
two dozen hares paid the penalty with their lives.

The four greyhounds belonging to the plantation were among these
poisoned hares almost every day; still I never saw one of them attempt
to feed upon the poisoned hares; certain it is that not one of them met
his death from this cause.

As the mixture is saturated with water before it is put among the
plants infested with locusts, there is no danger of its being blown about
by the wind ; and tjiere is also very little danger of its being deposited
upon the fruit by the feet of birds and insects that may have alighted
upon the mixture and afterwards flown to and alighted upon the fruit.
As the mixture becomes dry its particles adhere together, forming a
solid mass which could not be blown about by the wind.

I have never seen this poisonous mixture used in grain fields, but
know of no reason why it would not prove very effectual in such fields.
Great care should be exercised in using it in alfalfa fields, but if it were
placed upon small pieces of boards it could doubtless be used with en-
tire safety in such fields; but of course it would not be safe to pasture
any animal in such fields, even after the poison had been removed.

Where it is desired to destroy locusts infesting trtjes or shrubs in
places where it would not be safe to use the poisonous mixture described
above, this can be accomplished by placing blankets upon the ground
beneath the tree or shrub and spraying the latter with a solution com-
posed of 1 pound of buhach thoroughly stirred in 10 gallons of water.
This solution will be more effectual if 2 or 3 pounds of glucose is added
to it, first dissolving the glucose in hot water; the addition of the glu-
cose is for the purpose of causing the solution to adhere more firmly to
the bodies of the locusts, while its presence does not appear to have an
injurious effect upon the leaves of such trees as the Carolina Poplar.

The best time lor applying this solution is late at night, and the stiller
the night the more effect the solution will have upon the locusts. In a
few minutes after it is applied the locusts will begin to drop down upon
the blanket placed under the tree, and in the course of half an hour all
of the locusts that have been touched by the solution will be lying upon
the blanket in a perfectly helpless condition, when they can easily be

17

destroyed. One way of accomplishing this is to gather the locusts in a
pile, cover the latter with straw and then set fire to it; or they may be
collected in grain sacks and immersed in scalding-hot water until life
is extinct, after which they may be fed to hogs or to poultry.

One of the best nozzles that I have ever used for spraying this solu-
tion is the u Cyclone" nozzle, originally introduced by the Department
of Agriculture. It throws a very fine spray, and by its use the upper
as well as the under surface of the leaves can be directly sprayed — an
object that could not be attained in using the old "San Jos6" nozzle,
which threw a spray from its end instead of from one of its sides.

10010 CO 2

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