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U. S. DEPARTMENT OF AGRICULTURE.
division of entomology.

Bulletin No. 11.

REPORTS OF EXPERIMENTS

WITH

VARIOUS INSECTieiPv'Sro^mCES,

CHIEFLY UPON

INSECTS AFFECTING GARDEN CROPS,

UNDER THE DIRECTION OF THE ENTOMOLOGIST.

WASHINGTON:

GOVERNMENT PRINTING OFriCE.

18SG.

9228— Ball. 11

\

V t,

3521a

LETTER OF SUBMTrTAL.

Department of Agricultuee,

Division of Entomology,
Washington, D. 6\, January 14, 1880.

Sir: I have the honor to submit for publication Bulletin No. 11 of
this Division, which contains in condensed form the results of a series of
experiments with insecticides, carried on by certain agents of the Divis-
ion during the past summer.
Respectfully,

0. y. EILEY,

Entomologist.
Hon. Norman J. Colman,

Commissioner of Agriculture.

I

EXPERIMENTS WITH INSECTICIDES

INTRODUCTION.

There are a Dumber of remedies against insects, ^vliicli have been pro
posed from time to time, and which have been publislied without any
definite record of experiment, their reputation resting upon hearsay
evidence. The lisc of such remedies is growing longer every day,
and with a view of testing some of those which are most frequently rec-
ommended, in order to enable us to speak with difiniteness concern-
ing their value, we prepared a list early in the summer and sent dupli
cates to two of our agents, Prof. H. Osborn, at Ames, Iowa, and Mr
F. j\I. Webster, at La Fayette, Ind. At the same time, being desirous of
testing the infusions and decoctions of certain plants popularly" sup-
posed to have insecticide properties, we engaged ^Ir. Thomas Bennett,
of Trenton, N. J., a practical gardener of manj' years' experience, to ex-
periment in this direction. The reports of these three gentlemen are
subjoined, ami their results, thouiih in the main negative, are neverthe-
less of considerable interest and value.

KEKOSENE WITH MOLASSES.

It will be noticed that the kerosene emulsion used by IMessrs. Web-
ster and Osborn was made of equal parts of kerosene, molasses, and
water. Tiiis method of making an emulsion was first suggested to us
by i^Ir. E. S. Goff", of the New York agricultural experiment station at
Geneva, N. Y., early last August. Mr. Gofif had made what he thought
a tolerably perfect emulsion with these substances by using a crude
sorghum molasses, and his experif^nce at once interested us on account
of the fact that the mixture was made without heat, and because of the
probability that the molasses would render the dilute emulsion more or
less adhesive. After a long series of experiments, however, ^Ir. Gofif
came to the conclusion that he had overestimated thc^ value of the prep-
aration. We quote from his last letter on the subject:

*'l write to say that after abundant experimenting with the molasses-
kerosene emulsion, of which I wrote to you in August last, I fail to find
it equal to the soap emulsion. By boiling the molasses and water and

adding the kerosene to the hot solution, a very fair emulsion may be
made, but on standing, a fermentation seems to take place which causes
it to separate, and after that it will not remain mixed. The unexpected
success of my first attempt with the very thick sorghum molasses led
me to premature and uuwarrautable conclusions."

Following out the first suggestion, Professor Osborn found it impos-
sible to make a stable emulsion from the cold mixture of equal parts of
molasses, kerosene, and water, using ordinary low-grade New Orleans
molasses, no matter how violent and i)rolonged the agitation. In from
fifteen to twenty minutes, at the most, the oil would almost entirely sep-
arate from the mixture, rendering necessary its immediate use after
preparation.

COLD WATEB AND CABBAGE WORMS.

In addition to the results of the experiments with cold water as a
remedy for cabbage-worms, as given by both Professor Osborn and Mr.
Webster, we have received several communications since our publica-
tion early in the summer, in the columns of the Rural New Yorker, of
the suggestion* which originally came to us from Mr. 0. n. Erwin, of
Painted Post, N. Y. All of these communications are condemnatory
of the remedy. We extract from one (written by Mr. E. S. Goff) an
experiment which is worthy of publication in this connection :

In experimenting witli ice- water for tlie cabbage caterpillars I tried to intensify the
conditions as mucb as X'ossible. I immersed leaves having the caterpillars upon them
in Ice-vrater, leaving them there a quarter of a minute. I then removed the leaves to
a bench on the west side of the house, about 3 o'clock p. m., on a very hot day. Tbe
temperature must have been at least 100 degrees. Half an hour later I examined
them and fonud the leaves very much withered and becoming brown from the heat,
but the worms had crawled to the rear side and were exhibiting no inconvenience.

In our article just mentioned we left the question as to the efficacy
of the remedy open to experimenters, but the positiveness of Mr. Er-
win^s assurances, and the thorough, careful tone of his letter, inclined

* The text of this suggestion was as follows:

"Mr. Charles H. Erwin, of Painted Post, N. Y., has accidentally hit upon a simple
and yet, according to his experience, so perfect a remedy for the imported cabbage
worm that I wish to give his experience as much publicity as possible, that it may
be widely tested, and, if possible, verified the coming season. It is (to sum up an
extended experience which he narrated) simply ice-cold water, or water but a few
degrees warmer than ice-water, sprinkled upon the worms during the heat of the day.
Mr. Erwin found that such an application in the hot sun caused them to quickly let
go their hold upon the leaves, curl up, roll to the ground and die, while the cabbage
Bufiered nothing, but looked all the fresher for the application. Should this method
prove as successful with others as it has with him, it is evident that we have here a
remedy of very general application, and one which in cheapness and simplicity far
transcends the pyrethrum, which, since I first discovered its value for the purpose
in 1880, has been, on the whole, our safest and most satisfactory remedy against Pieris
rapae. Where ice is readily obtainable, as in the more northern States, or where cold
springs are found, Mr. Erwin's discovery will prove of very great value to cabbage-
growers, and will prove as useful against some other cabbage worms."

us to believe that there might be somethiug in the remedy. When
these adverse reports came in we wrote to Mr. Erwin to inquire whether
he had made further experiments and for further evidence. He repUed
as follows, August 23, 1885 :

I received last Thursday evening your assistant's (L. O. Howard) report of your uu-
snccessfal trial of tho "cold-water remedy " for cabbage worms. I have since called
upon two old gardeners in the vicinity, who bad used it. Mr. Thomas Homer was the
Duly one whom I found at home, and he was ill. When I told him tho result of your ex-
periments he interrupted me by saying: "They have not used very cold water, or
have used a rose-sprinkler when they should have thrown away the rose and used the
spout. I have used ice- water, aud it would make them turn white and would not
hurt the plants. Deacon Farwell used to make me use ice-water and drench the
plants at noon or in the hottest part of the day. I have used nothing else for many
years, and have lost scarcely a head of cabbage since I used it." I have in answer
quoted this honest old Scotch gardener for the reason that for the last three or four
years I have not worked in or done any gardening for myself. I used to drench my
plants every few days, always in the warmest part of the day, or about the time the
pests were the most active aud destructive — when they w^ere on the upper side of the
leaf — and have been told by others that they have succeeded after the worms had
filled every crevice with their droppings and rejected chippings, which they had by
drenching cleaned out; and here you discover is another benefit and argument for a
copious shower of water.

Possibly those who have experimented have, through fear of injuring the plants,
hesitated to use water cold enough or have used it too sparingly and in the cooler
part of the day. In making the discovery I was too late to avail myself of caution
about the safety of the plant, and was compelled to solace myself with the idea that
if the cold had injured and killed them I was not in a worse predicament than before
using the cold water, for if I had killed the plants I had only anticipated a few days
the certain result of the pests.

Perhaps the vermin are of a tougher habit in a warmer climate, and I would not
hesitate to reduce the temperature of the water another degree or two aud be sure of
the top degree of the day to apply it.

Several persons have told me that they used it last season with success, and one
person that he had not been troubled this season, not yet having discovered any
worms; but until recently but few persons in our vicinity grew more than a hundred
plants. This season I have noticed not a few acres planted with cabbages.

Please have your tests made properly and in the right time, and I think you will
succeed. It may seem too simple to be of much benefit, and scarcely worth the tiial,
and single efforts may fail for want of a little care. Let them act as if there should
be no such thing as failure, and they will succeed. Drench more frequently.

In view of such positive statements on both sides we cannot consider
tho question as decisively settled yet, but a pretty strong case is made
against the remedy in the reports which now follow.

0. V. EILEY.

REPORT OF EXPERIMENTS AT LA FAYETTE,

INDIANA.

By F. M. Wkbster.

1. — Imported Cabbage Worm. {Pieris rapcc ScL.)

EXPEUIMENT 1.— ICE WATER.
(August 4, 1885.)

TcTtippTatnreof atmosphere about plants, 03^ F. Temperature of water,
40^ F. Dreucbed two cabbage plants, uow well headed and serioiislj'
infested.

Result, — None perceptible.

Experiment 2.— ICE WATER.

Temperatnro of atmosphere, 104^ 1^. Temperataro of water, 38^ F.
Drenched two plants.
Result — Xono arc injured, and only seem to have been displaced.

ExrERiMENT 3.— ICE WATER.

Attfliist 4, 1885. — Temi)eratnre of atmosphere, 98^ F. Temperature of
water, 3(P F. Drenched plants as before.

Result. — A number were washed off, but none died from the effects of
their cold bath.

ExPERiMKNT 4.— ICE WATER.

Temperature of atmosphere, 08^ F. Temi)eraturo of water, 34° F,
Plant seriously infested, larvjc from | inch long to full grown. Drenched
at 1.45 p. m., Sei)tember 11, 1SS5, by p )uri ng one quart water on head
of plant, thoroughly wetting all l;U'va3 visible.

Result. — At 5 p. m. all worms have returned to the leaves and are
actively feeding.

ExpEHiMEXT 5.— ICE WATER.

Temperature of atmosphere, 00^ F. Temi)erature of water, 3P F.
September 10, 1-J.45 p. m., ])')nred water from i>itcher on two plants.

Result — On one i)lant, W()r'm>!, even tiic smallest, i incli long, were
auinjured; on the other two small worms were found dead soon after.

9

10

These were discolored when found, and I cannot say whether they died
from the effects of water or from an epidemic disease that is destroy-
ing these larvse in great numbers j some on this same phxnt being af-
fected and afterwards died, and I think the latter more probably the

cause.

Experiment 6.— SALT WATER.

August 5. — Dissolved salt in water to fullest capacity. Drenched a
number of plants badly infested with larvte.

Result. — On examination, 24 hours after application, I find no dead
larvae, but the living are feeding in abundance.

Experiment 7.— SALTPETER AND WATER.

Dissolved in water to fullest capacity. Drenched ])lants thoroughly.

liestdt. — Examined 2i hours after application, but find none dead, nor

any diminution in the numbers of the living, which are feeding as usual.

Experiment 8.— CARBOLIC ACID AND WATER.

Solution of 1 part acid to 100 parts water. Drenched two plants.

Bcsull. — This injured both plants, one quite seriously, by kdling the
younger, tender leaves, while such of the larvae as were i)rotected by
these leaves did not seem to have suffered.

Experiment 9.— PYRETHRUM POWDER.

A mixture of one part of powder to three parts flour was thoroughly
dusted on plants with Woodason's powder bellows, care being taken to
get the mixture thoroughly introduced among the leaves and cavities
eaten out by the larvai.

This experiment was made in order to establish a basis from which
to judge of the efficiency of other insecticides. I will further state that
the x>yrethrura powder used was sent me from the Department last sea-
son (1884), and had been kept in a glass jar closely corked.

Result. — Fully three-fourths of the larvae were killed.

Experiment 10.— WOLFS SOAP.*

Solution of 1 ounce soap dissolved in J gallon of water, applied at a
temperature of yO^ F., by drenching plants thoroughly, first wetting
them with water, and drenching them with same a short time after ap-
plication of solution.

Result. — At least one-half of the worms were killed and the plants not

injured.

Experiment 11.— WOLF'S SOAP.

Solution as in 10. Sprayed lightly on several full-grown larvae and
confined them under glass.
Result. — None died.

Manufactured by the Milwaukee Soap Mauufucturiug Compauy, Milwaukee, Wis.

11

ExpEraMEXT 12.— WOLF'S SOAP.

Solution, 3 ounces soap to 1 gallon water; temperature 90^. Sprayed
on plants with the WootlasDn atomizer.

Eesidt. — Seems to have been rather more effective than in experi-
ment 10.

Experiment 13.— WOLF'S SOAP.

Solution as in Experiment 12. Drenched plants thoroughly.

Liesiilt. — Does not seem to have been any more effective, although a
much larger amount of the solution was used. The spraying method
seems the more satisfactory.

Experiment 14.— WOLF'S SOAP.

Solution, 4 ounces soap dissolved in 1 gallon water. Sx^rayed on wet
surface of leaves and head.

Result. — Killed a large number of the larvae, but by no means all of
them.

Experiment 15.— BUCKWHEAT FLOUK.

Dusted the article usually put up for family use on a number of in-
fested ])lants.
ResulL-^The larvae did not seem to suff'er any inconvenience.

Experiment 16.— BUCKWHEAT FLOUR.

Placed 11 larviB in some of this same flour, and covered with glass.
Result. — Forty eiglit hours after, none had died, while some had
climbed to top of glass and pupated.

Experiment 17.— AMMONIA AND WATER.

Solution of 3 tablespoonfuls of ammonia to 1 gallon of water. Ap-
plied with syringe.
Result. — Xone were injured by the application.

Experiment 18.— POWDERED ALUM.

Applied to dew-wet leaves at 8.10 a. m., abundantly.
Result. — Cannot see that any are destroyed.

Experiment 19.— COPPERAS AND WATER.

Dissolved one-half ounce copperas in 1 pint water j drenched several
plants.

Result. — This only seemed to cause the worms to seek less exposed
positions. Watched for a number of days, but found none dead.

12

Experiment 20.— BLACK PEPPER.

Applied the ground article of commerce copiously to two heads of
cabbage.

Result. — T could not see that it affected those which came in contact
with it, and all continued to feed as though no a])plication had been made.

Experiment 21.— CARBOLIZ ED LIME MIXTURE.

Mixture of carbolized lime 1 part, quick lime f part, gypsum 20 parts.
Dusted mixture on two plants.

Result — Twenty-ibnr hours after, tlie worms were crawling about on
the leaves, feeding, and altbough some of the powder adhered to their
bodies, I saw no fatal results.

Experiment 22.— TAR WATER.
Sprayed on plants.
Result. — None apparent.

Experiment 23.— TOMATO WATER.

Steej)ed leaves of tomato vines, and applied strong decoction.
Result. — As in preceding.

Experiment 24.— ARKANSAS IXSECTICIDE.*

Placed 24 larvae on leaf of cabbnge, and dnstcd both leaf and worms
thickly with the insecticide, atl0.2oa.m., August 25. Theleaf and worms
were confined under a glass.

Result. — At l().2o next day, they seemed to be feeding from some parts
of the leaf not covered with insecticide. August 27. they did not seem
to relish the leaf with the insecticide thereon, but found enough not at
all or thinly covered to keep them alive. This is not of i)ractical
utility for large plants, but might do on those very young.

Experiment 25.— ARKANSAS INSECTICIDE.

Tested this thoroughl}' on plants, with results like those on leaf un-
der cover. In this experiment the larviie were watched closely for a
period of four days.

Experiment 2G.— SOLUBLE PINOLEUM.t

Solution of 1 part pinoleum to 40 parts water, sprayed copiously on
plajits in jrarden, August 25.

''Miinufacriired by Hoag & Beecher, Jiidsoiiia, Ark.

tMiinufiictnred by Hunsen & Siiiitli, VViljiiingtoii, N. C.

A saTiiple of this "soluble iiinoleiiiu" was .also sent to our agent at Cadet, ^Hs-
souri, Mr. J. G. Barlow, who reported iii brief, as follows: "Have experiiueuted a
little with the soluble piuolenm sent to me by your tlesire from Norlli Carolina. I
found that a soliitiou of one part to 10 of water was uofc too strong for larvio of

13

Result. — On 27tli, not over 2o per cent, of worms were destroyed.
Living worms abundant, showing- no effects whatever.

ExrEiUMENT 27.— SOLUBLE PINOLEUM.

Solution the same as in experiment 2G. Placed larvae on a leaf,
thoronglily spraying the same.

Eesult.— The larvai, with the exception of two small ones, survived,
and devoured the leaf.

Experiment 28.— SOLUBLE PINOLEUM.

Solution, 5 parts insecticide to 100 parts water. Sprayed on plants in
garden, September 2.

Result. — On 4th, a large number of larvse of various sizes were alivo
and active, about 40 per cent. api)arently having been destroyed.

Before further experiments could be made the larvae began to die
from effects of disease, and it was impossible to carry on the experiment
and get definite results.

Experiment 29.— KEROSENE EMULSION.

An emulsion consisting of equal x>'irts of kerosene, molasses, and
water, was dilated with tliree times its volume of water. Syringed
plants on September 7. Rain during night. Sprayed with same mix-
ture again, September 10.

Result. — September 8, 80 per cent, of all worms exposed were de-
stroyed. The result of second application could not be definitely de-
termined, as many were d.ying from disease.

I do not think younger iilants would witiistand emulsion of this
strength, but it would probably not be required for younger larvae.

Experiment 30.— CARBOLATE OF LIME.

Dusted plants thoroughly with carbolate of lime, using the Woodason
bellows.

Result. — Two days after, both large and small were still on the plants,
with no dead to be found.

Experiment 31.— HAMMOND'S SLUG SHOT.*

Dusted insecticide thickly over the plants with powder bellows, Sep-
tember 11. Kain fell on 13th. Dusted again on i4th.
Result. — September V2, (juite a nuniber were found dead.

NoctuidsandFieris. The solution in tlu'se pntpoi'tionswill kill these lurvai in IVoniouo
to two minutes. Plant-lico it will kill insrantly. Tried several Hpecinions of the
larviB of Sphinx quinqneiiincitlata, and lonnd to my surprise that not, even the solution ia
full 8tren;;th would kill them. I think the j)in(>lenni will be useful as an insectieido,
but not if mixed with so mneh water as the proprietors tlirect." — C. V. R.
'Manufactured by B. Hammond, Fishkill-on-IIudson, N. Y.

14

Of tbe first result I can only say that all larviie died from disease
shortly after, and at this date (October 19) the fact is clearly noticeable
in the leaves, those appearing previous to about the 15th are badly eaten,
while those that were put forth after that date are almost intact.

On October 1, the difference between the plants treated with slug shot
and those not treated was very apparent in the much more thrifty look
of the former, and the larger number of perfect leaves, and this differ-
ence is still very perceptible.

Just what per cent, of leaves was killed by insecticide, it is of course
impossible to determine, but the plants have a better look.

II. — Native Cabbage Worm. (Pieris protodice Boisd.)
Experiment 1.— HAMMOND'S SLUG SHOT.

Upwards of 50 larvae, taken from leaves of turnip, were placed in a
cage, and leaves, slightly dusted with the insecticide, placed therein.

Result. — Two days after, many were dead and others were dying. On
the third day nearly all were dead. Eventually but 5 pupated. The
single meal of dusted leaves proved sufficient, although amx)ie food not
dusted was afterwards supplied them.

III. — Fall Web- Worm. {Hyphantna textor Harris.)
Experiment 1.— WOLF'S SOAP.

Solution of 1 oz. soap to half gallon water; temperature, 90^ F.
sprayed with atomizer on foliage adjacent to web ; also in web, wetting
same quite thoroughly, nearly all of the caterpillars being within. -

Result. — Two days after ai)plication, about GO per crnt. were found to
have been destroyed. The foliage which had been sprayed did not ap-
pear to suffer for about three days, when the caterpillars again returned
to it and ate the leaves as though they had not been treated.

Experiment 2.— POTASSIUM SULPHIDE.

Solution, I part sulphide to 500 parts water; applied to web and fo-
liage with garden syringe.

Result. — On following day, a small per cent, appeared to have been
destroyed, but a week later the effects of the experiment could not be
noticed. Does not seem to render the foliage distasteful.

Experiment 3.— COPPERAS WATER.

Dissolved 1 oz. copperas in one pint of water; drenched web, and
thoroughly wetted foliage.

Result. — One day after, many caterpillars were dead and others scat-
tered about in the web, seemiugh^ very sick. Five days after, the foliage
remains untouched and all are dead.

15

Experiment 4.— COPPERAS WATER.

Dissolved 1 oz. in 1 quart of water. Used as in previous experiment.
Result. — It does not seem to have affected the larvae.

Experiment 5.— TAR WATER.

This water had been standing for several days in a cask partly filled
with tar. Water applied with syringe, wetting larvae and foliage.

licsult. — On first day after, none appeared to have been injured, and
many were feeding. Five days after, the results were as on the first.

Experiment C— AMMONIA WATER.

Solution of 1 tablespoonful to 1 pint water. Drenched as in experi-
ment 5.

Result. — First day after application, none injured. Five days after,
the situation is unchanged.

Experiment 7.— CARBOLIZED WATER.

Solution, 1 part carbolic acid to 12S i)arts water. Drenched web
thoroughly.

Result. — First day after application, none injured. Five days after,
situation unchanged.

Experiment 8.— TOMATO INFUSION.

Drenched web with strong infusion.

Result. — First day after api^lication, none injured. Five days later,
no change.

Experiment 9.-CARB0LATE OF LIME.

Dusted young larvae and the leaves on which they were feeding,
thoroughly.

Result — First day after application, a few seem to be dead. Second
day, not over 10 per cent. v>'ere injured.

Experiment 10. -SOLUBLE PINOLEUM.

Solution of 1 part pinoleum to 32 parts water. Sprayed several col-
onies and also adjoining foliage.

Result. — After four days all seem to be active, except a small per cent,
that were drenched more thoroughly than the rest.

Experiment 11.— POTASSIUM SULPHIDE.

Solution of 1 part sulphide to 500 parts water. Sprayed on j'oung
caterpillars less than one-half inch long.
Result. — None were destroyed.

16

IV. — Colorado Potato-Beetle. [Dorypliora lOUneata Say.)

Experiment 1.— WOLF'S SOAP.

Solntion, 1 ounce to 1 gallon of water. Temperature normal. Sprayed
on a number of adults.
Result. — Twenty-four hours after, none were injured.

Experiment 2.— WOLF'S SOAP.

Solution and temperature same as in Experiment 1. Sprayed larvae
of various sizes about as I would apply Paris green and water.
Result. — Only a small number of tbe youngest were destroyed.

Experiment 3.— WOLF'S SOAP.

Solution of 3 ounces to 1 gallon of water, applied to nearly full-grown
larvae on potato vines.
.Result. — Nearly all were alive next day.

Experiment 4.— WOLF'S SOAP.

Solution of 3 ounces to 1 gallon of water. Sprayed on tomato vines
being eaten by nearly full-grown larvae and adults.

Result. — Two Lours after, both larvae and adults had left the vines,
but I found no dead. Three days after, adults were again feeding on
the same vines, but no larvae were observed to return.

Experiment 5.— AMMONIA AND WATEE.

Solution of 3 tablespoonfuls of ammonia to 1 gallon water. Sprayed
on plants infested bv larvae of various sizes.

Result. — One day after, only a very few of the youngest larvae had
been destroyed.

Experiment C— AMMONIA AND WATER.

Solution as in Experiment 5. Placed enough of this mixture in glass
to cover bottom ; i)ut in glass nearly fall grown larvae and beetles, shook
thoroughly, turned off fluid and insects and inverted the glass over
them.

Result. — Xot a single larva or adult was injured.

Experiment 7.— AMMONIA AND WATER.

Solution, 1 tablespoonful to 1 quart of water; applied as in Experi-
ment 0.

Result. — The same as in previous experiment.

Experiment 8.— CARBOLATE OF LIME.

Sprinkled thickly on tomato vines that were being eaten by adults
and larvae.

17

Result. — Twenty-four hours after application the insects had appar-
ently deserted the vines, but I found none dead.

Experiment 9.— CARBOLATE OF LIME.

Sprinkled larvae and adults with carbolate of lime, and placed under

glass.
Result. — IN'one died.

Y. — Striped Cucumber Beetle. (Didbrotica vittata Say.)
Experiment L— WOLFS SOAP.

Solution, 3 ounces to 1 gallon water, applied at normal temperature,
to adults.
Result. — After G hours none appeared injured.

Experiment 2.— CARBOLATE OF LIME.

Dusted on male blossoms of squash in which six adults were feeding
on the pollen.
Result. — Two days after, they were dead in the blossom.

YI. — Margined Blister Beetle. {Epicauta cinerea Forst.)

Experiment 1.— TAR WATER.

Applied to a row of mangel wurzels, seven rods in length, which
was being seriously defoliated by this insect.
Result. — Five hours after, only an occasional plant was being eaten.

Experiment 2.— WOLF'S SOAP.

Applied solution of 3 ounces of soap to 1 gallon of water to a row of
mangel wurzels beside that used in Exx)eriment 1.

Result. — Five hours after, only three beetles were found on the leaves,
but none were found dead or injured.

Experiment 3.— COPPERAS WATER.

Solution, 1 ounce to 1 pint water sprayed on row next to Experi-
ment 2.

Result. — Five hours after, the number of beetles feeding on leaves
does not seem to have diminished.

Note. — Three days after, the beetles had returned to all three rows
in about equal numbers.

YII.— Ants.

Experiment 1.— CARBOLIC ACID.

Large numbers of ants had excavated burrows between the crevices
of a brick walk in my yard, and kept the entire walk in an unsightly
condition by reason of the numberless little circular heaps of excavated
02G8— Bull. 11 2

18

earth. To these burrows I applied about a tablespoonful of a solutiou
of 1 part carbolic acid to 64 parts water.

Result. — ^o ants appeared in the burrows, and no attempt was made
to re-establish these burrows again.

About two weeks later, a few burrows were excavated in the crevices,
and these were treated in the same manner. The results were as fav-
orable as before, and up to date (October 20), no ants have attempted to
work in crevices of the walk.

Experiment 2.-CAEB0LIC ACID.

Solution of 1 part acid to 128 parts water was applied to burrows,
about two-thirds of a tablespoonful to each burrow.

Result. — In some cases, 24 hours after application, the ants had re-
turned to work in the old burrows, but in most cases the burrows
showed no signs of life.

Experiment 3.— CARBOLIC ACID.

Solution of 1 part acid to 96 parts water, aijplied as in Experiments
2 and 3.

Result. — Only in a single instance was any attempt shown to dig out
the old burrows, and about this were a. large number of dead ants that
had been removed m re-excavations.

A few attempts to excavate burrows in the vicinity of the old ones
were observed a few days after first application, but these burrows were
drenched as before, and no attempt was afterwards made to excavate
between the crevices in that vicinit^^

Experiment 4.— COPPERAS WATER.

Solution of 1 ounce to 1 pint water was poured into the burrows.

Result. — ^ext day the ants were busily engaged in clearing out the

old burrows.

Experiment 5.— AMMONIA WATER.

Solution of three tablespoonfuls to one gallon water was used, as in
previous experiments.

Result. — Same as in Experiment 4.

Experiment 6.— TAR WATER.

Drenched as in previous experiments.

Result. — The ants did not attempt to clear out the old burrows, but
excavated others close behind them.

yill.— Lettuce Aphis. (Siplwnophora lactucce Linn. ?)

Experiment 1.— SALT WATER.

Dissolved salt in water to its full capacity. Sprayed solution on
lettuce plants infested, the aphids being on upright stalks and hence
easily reached.

19

Result. — About 50 per cent, were killed. A second application on

the following day was fatal to nearly all of the remainder, and to the

plant also.

Experiment 2.— WOLF'S SOAP.

Solution of 3 ounces soap to 1 gallon of water. Sprayed on aphid s
on plants.
Result. — Thoroughly effective.

IX. — WooLY Apiiids. {Species various.)
Experiment 1.— WOLF'S SOAP.

(Species on Tree-Ferns in green-house.)

Solution of 4 ounces soap to 1 gallon of water. (Temperature normal.)
Sprayed ou foliage previously wetted; drenched with water soon after
application of solution.

Result. — This made no impression on the insects.

A second application after 24 hours had elapsed from first.

Result. — Only a small per cent, were destroyed.

A third application, the foliage not beiug sprinkled with water after
application of solution, proved fatal to the aphids and killed the entire
foliage of the plant.

Experiment 2.— TAR WATER.

WooLY Aphis of Apple. [ScMzoneura lanigera Hausm.)

Tar water sprayed on infested branches, August 31.

Result. — September 2, does not seem to have had the least effect.

Experiment 3.— SOLUBLE PINOLEUM.

Species as in Experiment 2. Solution of 5 parts pinoleum to 100

parts water. Sprayed on branches with atomizer.

• Result. — On following day, many active lice were observed. Three

days after, they were abundant, and five days after, were as abundant

as at first.

Experiment 4.— SOLUBLE PINOLEUM.

Species as in Experiments 2 and 3. Solution of 15 parts pinoleum to
82 parts water. Sprayed ou branches, September 15.

Result. — Three days after application, none were to be found, and up
to October 20, none have appeared on these branches.

Experiment 5. -KEROSENE EMULSION.

{Glyphina eragrostidis Middleton.)

An emulsion, composed of equal parts kerosene, molasses, and water,
was diluted with three times its volume of water. This was sprayed
on aphids, September 12.

20

Result. — September 13, found hardly a trace of aphids. September
16, a very few Lave appeared. September 25, tliey have spread over the
grass, and are as abundant as ever.

Experiment 6.— SOLUBLE PINOLEUM.

Solution of 5 parts pinoleum to 100 parts water, sprayed on same
species, September 3.

Result. — September 4, none appear affected and none are destroyed.

X.— Apple Aphis. [Aphis mali Fabr.)
Experiment 1. -SOLUBLE PK OLEUM.

Solution of 15 parts pinoleum to 85 i^arts water. Sprayed on twigs
and leaves.
Result. — The aphids were completely destroyed.

XT. — Apple Leap Skeletonizee. {Pempelia liammondi Eiley.)
Experiment 1.~S0LUBLE PINOLEUM.

Solution of 15 parts of pinoleum to 85 parts of water. Sprayed over
leaves, September 15.

Result. — Probably 75 per cent, of the larvae were destroyed, but full-
grown larvae were observed on leaves, October 1st.

Experiment 2.— HAMMOND'S SLUG SHOT.

Dusted leaves seriously affected by larvae, September 15, when no dew
was on them.

Result. — September 16, 50 per cent, are dead. Dusted again, on
17tb, on dew-wet leaves. October 1, not one living larva could be found
on the leaves that had been dusted, while numbers were on leaves not
treated. September 2G, nine days after, a larva established itself on
one of the dusted leaves, ate a very small spot on the leaf, and died.

XII. — Yellow NECKED Catekpillar. (Datana ministra Dru.)

Experiment L— POTASSIUM SULPHIDE.

Solution of 1 part potassium to 500 parts water. Sprayed on larvae
feeding on waluut.
Result. — The larvae were uninjured.

Experiment 2.— POTASSIUM SULPHIDE.

Solution as in 1. Applied to larvae clustered on trunk of tree, prepara-
tory to molting.

Result. — The larvae molted, and ascended the tree. I could not see
tLat the application had the slightest effect.

21

EXPERIMEXT 3.— WOLF'S SOAP.

Solution, 4 ounces to 1 gallon of water. Sprayed on larvae feeding on
walnuts.
Result. — The larva? only changed their location for a branch higher up.

EXPERIMKNT 4.— COPPERAS WATER.

Solution of 1 ounce to 1 pint of water. Sprayed two colonies of nearly
full-grown worms.

EcsuJt. — This seemed to destroy a very fewlarvce, and the remainder
changed their location on the tree.

ExrERiMENT 5.— COPPERAS WATER.

Solution as in Experiment 4. Sprayed cluster on trunk of tree.
Result. — They molted, and ascended the trunk and began feeding.,

Experiment G.— SOLUBLE PINOLEUM.

Solution of 1 part pinoleum to 32 parts water. Sprayed one cluster
on leaves and another on trunk.

Result. — There appears to be some reduction in the numbers of those
feeding, and those on trunk were destroyed .

Experiment 7.— SOLUBLE PINOLEUM.

Solution of 5 parts of pinoleum to 100 parts water. Sprayed half
grown larvDc on branch high up in tree, so that I could only give them
a slight wetting.

Result. — Xone were injured, and, two days after, they were feeding as
though nothing had happened.

Experiment 8.— SOLUBLE PINOLEUM.

Solution of 15 parts to 85 parts water. Sprayed copiously on cluster
on trunk of walnut tree.

Result. — About 50 i)er cent, were killed, some dying after the second
day. The cluster became detached from the tree and fell to the ground,
but a few larva? detached themselves from it, and again ascended the
tree, and molted.

Experiment 9.— AMMONIA WATER.

Solution of 1 tablespoonful to 1 pint of water. Sprayed cluster on
trunk of tree.
Result. — They molted and ascended the tree.

Experiment 10.— KEROSENE EMULSION.

An emulsion, of equal parts kerosene, molasses, and water, was di-
luted with three times its volume of water. Sprayed on cluster on
trunk of tree.

22

Result. — I^ot over 20 per cent, molted, and many of these died before
ascending the tree.

Experiment 11.— KEEOSENE EMULSION.

Emulsion the same as in 10. Sprayed on caterpillars on leaves and
twigs in walnut tree.

Result — All disappeared within forty- eight hours after application.

Experiment 12.— HAMMOND'S SLUG SHOT.

Dusted leaves on which nearly full-grown larvse were feediqg.

Result. — The worms changed their position soon after to a distant
branch, but their route was clearly indicated by occasional dead larvse
hauging to the branch along which they had crawled, and soon after all
disappeared.

I

REPORT OF EXPERIMENTS AT AMES, IOWA.

By Prof. Herbert Osborn.

Sir : I send you with this a summary of my tests of various reme-
dies for cabbage insects, &c. My work has been almost entirely con-
fined to cabbage pests, as some of the insects mentioned in your in-
structions had already passed the active stages, while some mentioned
have not appeared in this locality. There are no gardens worthy the
name in the vicinity, so that some of the most common vegetables, with
the insects infesting them, have not been within my reach. Even
cabbages were rather scarce this year. One patch of about eighty plants,
on the college farm, was quite well stocked with insects — Pieris rapce,
Plusia hrassicce, Plutella cruciferarum^ Aphis brassicce^ Haltica striolata^
&c. Another patch on the college farm, containing a greater number of
plants, contained scarcely one with a solid head, and they were so poor
that the insects seemed to consider them beneath notice. Scarcely a cab-
bage worm could be found there during the entire fall.

A small i:)atch of about eighty plants, on a farm owned by Professor
Mount, was quite free from worms till the 1st of October, after which
they were more plentiful, and served for experiments with several sub-
stances. The small number of plants necessitated experimenting on a
few for any one substance, and going over the same plants with other
remedies after the lapse of a few days, sufficient to note results.

The appearance of the epidemic disease among the cabbage worms,
mentioned in connection with the cold-water experiments, made it
necessary to be very careful in judging of results. It commenced
about the middle of September, and continued till all the worms disap-
peared, great numbers dying from it, though all the plants in a patch
would not be found to contain diseased worms at the same time (at one
time a great many dead or diseased worms could be found at one end of
the patch and none at the other). The characteristic appearance of the
worms dying of this disease makes it easy to distinguish them for a time
after death, but later they turn dark and shrivel, and do not differ much
from worms that have been killed by parasites or predaceous insects or
by application of remedies. Parasites have been quite abundant, both
in Aphides and worms. Coccinella larvae and adults, Syrphus larvae,
and Ichneumons were on hand, and I noticed one cabbage worm im-

24

paled on the beak of a soldier-bug, and others which appeared to have
had their life extracted by the same foe. Altogether the worms and
Aphides have had a hard time. Only a small projjortion of Pier is rapw
could have pupated in a healthy condition.

Concerning the cold-water remed^^, to which you desired me to give
particular attention, my tests, while not crucial, for the reasons stated,
satisfy me that it has no direct effect on the worms. I applied the water
ice-cold (at one time with temperature of air above 80^ F.), so as to
thoroughly soak many of the worms which I could see, and in one in-
stance I placed lumps of ice on a couple of cabbages so as to come in con
tact with worms, and so that the water running from these lumps would
give them a cold bath for some time, but could not discover any worms
dead from its effect. However, the worms on the plants treated with
the ice water died off ver^^ rapidly with the micrococcus disease, and I
think it possible that the treatment made them fall an easier prey to
this epidemic.

Kespectfully,

HERBERT 0SB0E:N^.

Prof. 0. Y. Riley,

U. 8. JEntomologist.

TESTS OF REMEDIES.

Kerosene and Molasses Emulsion. — Made by shaking together violently
equal parts ot kerosene, molasses, and water. Emulsion thus formed
would remain for some minutes, but gradually separate. This emulsion?
applied September 10, 1885, killed cabbage worms of all kinds, Ai:)liides,
and other insects, i>rovided it came in contact with them 5 but owing to
their secreting themselves so fully within the leaves, many escaped.
Even when applied so thoroughly as to kill the leaves of the plant,
numbers of the worms would escape, and were seen afterwards as
healthy as ever upon the plants treated with the emulsion. Not more
than half the insects were killed by this treatment.

'Cost of this application, one-fifth of a cent per cabbage, not counting
time of making or applying.

Cold-icater Application. — September 19, applied cold water from a well*
direct to cabbage worms, at about 11 a. m.; day warm (77° F., at noon).
Examinations later in the day showed no result. On the 21st, on plants
thus treated were a number of dead larvae, also many alive and healthy.
Those dead had the appearance of worms dying from the micrococcus
disease introduced from Illinois two years ago, and microscopic exam-
ination of the body contents showed them to be swarming with micro-
cocci apparently the same as those in the disease of two years ago.
Later many of these dead larvse were found on plants not treated, sd it

* Temperature of water in well here is about 40° F.

25

is uncertain whether the applications of water produced any effect. On
September 21, at about 11.30 a. m, (temperature at noon, 81° F.), applied
ice water to cabbage worms. Worms were decidedly disturbed when
it came in contact with them, but I could get no positive evidence of
any of them dying from its effects. On the plants thus treated the
worms soon after began dying, as in the case of the first application of
water; but as they also died on plants not treated, it is unsafe to con-
clude that this application induced the disease. Ou these plants
worms died off till scarcely a living worm could be found. October G,
on farm of C. F. Mount, applied cold water to cabbage worms (day
cool; at noon, 51^ F.) — water cold enough to make the worms curl uj)
and drop when it came in contact with them. Examined October 7,
and could find none killed or dying from effect of this application.

Carbolic Acid in Water. — September 21, applied carbolic acid in water,
very dilute (1 dram carbolic acid to 1 gallon water). An hour or two
later no effect could be noted, nor on subsequent days. September 26,
applied carbolic acid and water to plant-lice on squash and on cabbage,
and to Avorms on cabbage and i^arsnips. Up to October 1 no effect was
to be noted from this application. On October 6, on farm of C. F.
Mount, ai)plied carbolic acid and water (one-half ounce to gallon of
water), sprinkling eighteen plants. On October 7,ou plants thus treated
a number of dead worms were found, but a considerable number had
escaped. Professor Mount applied carbolic acid, about one-half ounce
to one gallon of water, for the first brood of worms, and his cabbages
were not injured till late in fall. He does not know that any were
killed, but thinks it i^revented injury.

Bran. — October 0, api^lied bran to cabbage i)lants on which worms
were quite plenty. October 7, found the worms as numerous and
apparently as healthy as before. Perhaps they avoid places where bran
is thick.

iSalt Solution, — September 21, this solution was applied to cabbages,
on which were numerous worms and Ai)hides. Worms neither killed
nor driven away. Aphides unaffected, except where they were washed
oft'. The plants were watched until the 25th, and no result noted. The
solution was also applied to Aphides on weeds, with no effect. Was also
ai)plied as a warm solution to Aphides on weeds, and some branches
thickly covered with the insects were dipped into the solution, without
effect on the Ax)hides that held to the plant. Some were washed off' or
crushed, but the colonies a few hours later and on following days were
as thickly populated and as healthy as ever.

Saltpeter Solution. — September 21, applied saltpeter in solution to cab-
bages on which worms and Aphides were abundant. Neither seemed
affected by the application. Up to September 25 there were no signs
of injury. October G, applied solution of saltpeter to eighteen cabbages
on which w^orms were tolerably plenty. October 7, no eff'ect to be seen ;
worms plenty and healthy.

26

AZwm.— September 26, dusted pulverized alum on cabbages where
worms and Aphides were abundant. Up to October 1 no effect was
noted on either. September 26, it was applied in solution to them, but
no signs of injury to either worms or Aphides were observed. October
6, applied to cabbages on which worms were plenty. October 7, worms
as healthy and numerous as ever.

Kerosene in Ashes. — On October 4, applied this mixture to cabbage
plants on which worms and Aphides were plenty, and watched for
some time to see the effect. Could not find any worms killed by the ap-
plication, though many were seen with the oily particles in contact with
them on the leaves or adhering to their hairs. On subsequent days no
decrease in numbers could be noted as a result of this application.
Aphides were killed in some instances, but their position under leaves
made it very difficult to dust them. The worms (P. rapce) seem to be
protected by their hairy covering, which prevents the particles from
coming in direct contact with the skin, and renders the spreading of the
oil less effective. The worms with smooth skin might be killed more
readily, but they were not plenty enough on the plants treated to enable
me to arrive at any positive conclusion.

Kerosene in Gypsum. — Applied on October 4, the gypsum containing
as much kerosen e as possible while allowing it to be dusted on the plants.
The results were the same as followed the use of ashes, but I found it
more difficult to mix and apply. There was a constant tendency to form
lumps too large to be dusted on the plants, and unless quite fine the par-
ticles will simply roll off the leaves.

Kerosene in Saivdust. — Sawdust thoroughly saturated with kerosene
was applied, October 17, to a number of plants on which cabbage worms
were but moderately plenty. They were watched for nearly two hours,
without any marked result. Unfortunately, I was prevented from
making any further observations for several days, and in the meantime
some severe frosts, the ravages of disease, and the maturing of the worms,
left scarcely a living worm to be found even on plants not treated.

Tomato-vine Infusion. — Applied, October 7, to 18 cabbage plants infest-
ed with cabbage worms. The plants were thoroughly drenched with the
infusion, and many of the worms were well soaked in it without appar-
ent inconvenience to them. On the following day the plants thus treat-
ed were as badly infested as before and the worms were all vigorously
feeding.

REPORT OF EXPERIMENTS AT TRENTON, NEW

JERSEY.

By Thomas Bennett.

Trenton, N. J., Ju7ie 15, 1885.

Sir : Under your direction I have tested the insecticide value, to a
limited extent, of five of the six vegetable substances you gave rae to
exi)eriineut with. These were as follows : Jamestown weed {Datura
stramonium)', tomato lenves {Li/cojyersicum esculentum) ; Eilder {Sambu-
cus)', Ailanthus; mandrake root {Podophyllum peltatuyn) ; and Tansy
{Taiiacetum).

At this date I have not been able to procure tomato leaves in suffi-
cient quantity to experiment with; the others I have. The first insect
that I found requiring attention was the green Aphis, or x^lant louse
{Myzus persicce), of the Peach, which was collected in great numbers on
six young peach trees in my garden. They were only on the ends of the
branches of the present summer's growth. I marked one tree, and pre-
pared a decoction and also an infusion of tansy in the following manner:

Tansy. — June 5: weighed a handful of tansy, weight J pound ; put it in
three quarts of water; set on to boil; let it simmer an hour, then set
away to cool. At the same time, made an infusion of ^ pound tansy by
pouring on three quarts of boiling water, and set away to cool. This ex-
tract 1 found much the stronger of the two.

The leaves of the peach trees were so curled that I could not apply

the liquid by other means than by dipping; besides, I wished to save my

liquid. I dipped one side of the tree in the decoction, the other side in

the infusion or extract. I found the liquid in both cases would wet the

leaf but not the insects. They seemed covered with an oilj^ substance

which prevented the preparation in both cases from adhering to them ;

and it would roll off'as water rolls from an oiled flag or pie(;e of polished

marble. Then I thought, as lye has an affinity for oils and grease, I

would try lime-water and also urine, in the proportion of first one-quarter,

then one-half; but although each proportion and each sort did some

good, they were not satisfactory. However, the insects did not increase

any, and I dipped them every day, for four days, and at this writing

(June 15) there are few to be seen.

87

28

Elder Leaves. — June 7: made an infusion of elder leaves and tops,
weiglit J pound ; poured on two quarts of boiling water; set on back of
range to draw ; time, two hours. I had expected a good result from elder,
as it has long been used by gardeners and farmers, combined with bur-
dock and walnut leaves, &c., as an application against insects ; but in
this case it did not seem to work well. I marked another tree, and ap-
plied it by dipping the ends of the branches. The water rolled off as
usual, and would not stick. I mixed a little alkaline lime-water, but it
seemed not to injure them in the least. I noticed that the infusion was
nauseous but not bitter. I cannot see how it acts as an insecticide unless
by the smell. Some insects have a great dislike to pungent and strong
smells. After the fourth dip, which was on the fourth day, I despaired
of its doing any good in this case, and so tried my next remed}^, which
was mandrake root.

Mandrciike Boot. — June 8 : made a decoction of mandrake root, 1 pound;
put in two quarts of water; let it come to a boil, and then simmer or
stew slowly for one hour. When cool it tasted very bitter and was
rather dark colored, and I had good hopes of it, in which I was not dis-
appointed. T applied it to another young peach tree, and also to a
young, six-yearold cherry tree, infested with black Aphides {^fyziis
cerasi). Three dips almost cleaned them entirely from the peach tree^
and also from the cherry tree, so that the Ladybug and her larvae made
short work of the few sickly ones that remained. I cannot account for
it, but this wash seemed to take a better hold of the insects, so that the
Peach Aphis would turn brown after the second dip; and in my subse-
quent experience I found that whenever the insects turned brown it was
a sure indication that their time was short. They would not increase
afterwards, and the Ladybug larvae soon destroy them. I also tried
this remedy on rose bush Aphis, with about the same result.

Ailantlnis. — June 9: made an infusion of 8 ounces of the leaves of
Ailanth us in two quarts of water ; let it draw two hours. The liquor was
very dark, and the infusion similar to elder in its effects ; the water rolled
off and would not adhere to the insects. An infusion of the bark was
clear, only slightly brown. I added some lime-water, for the purpose
mentioned in my first experiment, and also applied a little fine dust
through a small dredging box. This made the infusion adhere very
closely, and the Aphides succumbed after the third dip. It will be re-
membered in all these cases that I made only one dip each day, and
waited till next day to see its effects; then dipped again. ^S'o one need
be surprised that these different bitter and obnoxious plants had no
better effect on these insects when I say that I afterwards tried two of
the strongest vegetable bitters we know — namely, quassia and coloquin-
tida, or the colocynth gourd — with no better effect.

I may here remark that I bottled and labeled all those bitters for
other experiments.

N. B. — I have since found that the ailanthus bark contains the bitter
principle very largely, but takes a long time to draw.

29

Stramoniinn. — June 10: made an infusiou of 6 ounces of the leaves
and young tops of Stramonium in 3 pints of water. Let it draw two
hours. When cool I applied it as I did the others, by dipping the ends
of the branches. The liquid was not bitter, but I depended on the effects
of the poisonous narcotic principle, which, like its near relativ^e, tobacco,
it very largely contains. In this I was not disappointed, for, although
it would not adhere ver^^ closely, the Aphides seemed to diminish and die
after the third application ; and if any scattering ones remained they
were soon eaten up or destroyed by their enemies. T should note that a
few rose bushes, infested with Eose Aphis [Siplionophora rosw), were
treated in a similar manner to the peach and cherry leaves, but the lice
seemed somewhat harder to kill.

Alder Baric. — June 11 : I thought I would try an infusion of alder bark,
because it contained the tanning principle, which is an astringent, and as
all astringents, whether vegetable or mineral, are more or lessinsecticidal
in their nature, I thought that perhaps it might be of some value. I
found it had some effect as an insecticide, but as the infusiou is very
dark, almost as black as ink, and discolors the leaves a good deal, I
left it off and do not recommend it.

Quassia. — June 11: made an infusion or extract of quassia chips
or bark, ground fine. These are made more nicely prepared than for-
merly. Gardeners know well the power of this bitter, in greenhouses
and graperies, in keeping down Green Fly, as they call it [Siphonophora
viticola), also Thrips [Erytkroneura)^ and lied Spider {Tetr any elms). I
poured two quarts of boiling water on four ounces of quassia. This
made a strong inf'asion of a beautiful brown color, similar to the tea we
use from the shops. I thought surely this would kill at the first dip, but
it did not, though very bitter. It took three dips of this strong liquid
to kill these Aphides on the Peach, the Oherrj^, and the Rose, and then
there were some stragglers around, of which I could not be sure whether
they escaped from the effects of the dipping, or came in from other parts
of the tree or rose bush.

Coloquintida, or Colocyntli Gourd. — June 11: this bitter principle I have
formerl}' used to a limited extent, in greenhouses, and have a high o[)iu-
ion of its meritsj but quassia being so much cheaper and generally
effective, I have mostly used it. However, I procured an ounce of colo-
cynth, ground it up, and put on nearly a piut of boiling water, and drew
it as tea. It is very i)Owerful as a bitter, but it took three dips to erad-
icate the Aphides from the rose bush, peach, and cherry trees.

Furtlier Experiments. — Monday, June 15: went out a short distance in
the country, about one mile east of Trenton, to the lands occupied by Mr.
James McGrath, who is an extensive cabbage-grower, and got liberty to
make some tests with a view to preventing the cut-worm froui injuring
the young cabbages. I had previously learned that he was going to
plant on this day. Was allotted a piece to experiment on, that contained

30

60 plants to each row. I poured on tlie stems and lower ends of tlie
leaves of

Eow '^o. 1: Mandrake infusion ;
Row Xo. 2: Elder infusion;
Eow Xo. 3: Stramonium infusion;
Row Xo. 4: Ailauthus infusion;
and, Tansy beiug plentiful on the place, I made a strong infusion of it,
and wetted over 1,000 plants wbicli were to be planted on another part
of the lot. I also made a solution of

Alum, 2 ounces to 1 pint of water ;
Xiter, 2 ounces to 1 pint of water ;
Saleratus, 4 ounces to 1 pint of water;
Lime water, 4 ounces to one quart of water;
and applied these strong liquids to rows 5, 6, 7, and 8, which together
made 9 tests or experiments.

I did not examine these for results till June 29. The Tansy seemed
to show the best results, and I could only find 4 plants eaten off by cut-
worms.

The saleratus had been strong, and killed several plants, and I could
not pronounce any of the other experiments entirely successful.

Mr. McGrath had lost many plants in this lot of about four acres by
cut- worms during the last two weeks.

June 17: tried the effect of infusion of Ailauthus, Tansy, Elder, and
mandrake, sprayed on with a brush by drawing the hand lightly over
the brush till all the leaves were wetted. These did not give very sat-
isfactory results, though partially effective. Xext day, I thought I would
assist them with some cheap powders. I procured some gas lime, and
sifted it; and also made a powder of gastar and lime, then sifted. This
last was composed of ^ ounce of tar to 1 pound of lime. I also made a
preparation of quicklime, well sifted. After spraying the vines, and
making a number for each experiment, I proceeded thus —

Ino. 1. Elder leaves, followed by a dusting of gas-house lime.

Ko. 2. Stramonium, followed by a dusting of tar lime.

'Eo. 3. Mandrake, followed by a i)ure lime dust.

Xo. 4. Tansy water, followed by pure lime dust.

!No. 5. Ailauthus leaves tea, followed by gas-house lime.

]S"o. 6. Ailauthus leaves tea, followed by tar lime.

Ko. 7. Ailauthus, followed by pure lime.

!N"o. 8. Lime water alone, as a thin whitewash.

No. 9. Niter water alone, 2 ounces to L pint of water.

No. 10. Alum water alone, 2 ounces to 1 plot of water.

No. 11. Saleratus, 4 ounces to 1 pint of water.

No. 12. Gas lime and pure lime, mixed in equal quantities.

No. 13. Tar lime alone.

No. 14. Pure lime alone.

I had never seen potato vines more thickly covered with bugs than
these were when I commenced with them, owing to the fact of the

31

owner havinfi^ removed to the other side of the city, and not havin^- time
to attend to them. On Saturday, June 20, there were no bugs there.
I did not see them again till June 28, then I saw only 5 bugs on the lot.
I have given them another sprinkling of tar lime since then, and there
is not a bug to be found. I am sure they never got a particle of Paris
green.* As many persons have an objection to putting Paris green on
potatoes, I can recommend a dead shot made of one pint of gas tar to
1 peck of lime as an effectual remedy against potato bugs.

J'kily 15, 1885. — As you directed, I have continued through this month
to make experiments with the six vegetable substances yon advised,
namely, Ailanthus, Tansy, stramonium, Elder, mandrake, and tomato.

Before I proceed further, I wish to say that during the fore part of
this month I succeeded in cleaning a few hop vines in my yard and
those of some of my neighbors from two species of a destructive cater-
pillar, and also a species of Corens or Stink Bug, which was doing much
harm by sucking and killing the leaves of the vines. I herewith send
specimens of the bug and the caterpillar.t I made a powder of gas tar
and lime, which soon cleared the vines of every insect, and now there are
none to be found on them. I find this powder is good also for every
species of Plant-louse.

JuJy 6. — Collected these leaves and plants, and made strong infu-
sions. First tried them on the Cabbage Cut-worms, by burying a worm
one-half inch deep and within 1 or 2 inches of each cabbage plant, wet-
ting them thoroughly with each liquid, and labeling each one. At the
same time I tried Hansen & Smith's Pinoleum, diluted with 25 parts of
water. Next morning, when I went to examine my plants, I found the
worms had all moved away but one ; this one had been wetted with
tansy, was curled up in the usual way, and apparently in good health.
It was evident, however, they did not like their situation, for only one
ventured to cut his plant, and that was the one wetted with elder; he
was also gone.

I next tried the effect of these infusions on the Jumping Flea-beetle
(Haltica), on Early Dutch cabbages. Most of them proved very good, but
were most effectual when followed by a dusting of lime powder or i)laster.

The liquid adheres better after the garden syringe than the watering
l)ot. Infusions of ailanthus leaves and also of stramonium I have used
in former years for this and green fly and cabbage lice with good effect, but
they were mostly followed by a dusting of lime in fine powder. I would
remark just here that tobacco dust, lime powder, plaster, ashes, or soot
well mixed with five or six times its bulk of charcoal dust, or in fact any
other dust, will effectually keep off the Jum ping-bug, if the ground around
the plants be kei)t stirred; and here is where many fail in applying these
powders ; they do not seem to be aware that it is necessary to stir the

*I should note that the saleratus was too stroug, aud killed part of the leaves of
the potatoes as well as the bugs.

t These insects were Agrolis malefida, Arctia virginica, and Coreus tr talis. — C. V. K.

32

ground often around the plants. If a field of turnips or a bed of cab
bages, when just coming over the ground, be only lightly stirred, by
drawing a garden rake over the plants, along close to the rows, there will
be very little if any powder required, but this must be done often to keep
down this bug; and in this the secret of saving the crop lies, of which
few seem to be aware. These bugs seem to breed in and come from the
ground around the plants, but, it seems, cannot generate if the ground be
kept frequently stirred. This I have proved to my entire satisfaction ;
and wben the ground cannot be stirred, all of the above powders will
often fail.

I next tried the effect of these infusions on cabbage lice {Aphis bras-
sicce) on about 200 j)lants. Here, again, I found it was essential to fol-
low with the lime powder, for although these washes killed some and
stunned most of the others, yet it had not the powerful effect of the lime
powder. This, as far as I have gone, has proved effectual, and I think if
put on in time will keep down this pest altogether.

During this month 1 have also been trying to find out something to
prevent the Out- worm from injuring cabbages after being planted. I
have tried soft soap and tobacco water separately and combined, as a
dip, also Hansen & Smith's Pinoleum in 12 times its volume of water*
They were all too strong and killed many of the plants at first. Noth-
ing daunted, I tried again, at least the soap and tobacco. Infused two
ounces of tobacco stems in one quart of water, as a dip for the stems
and lower ends of the leaves. Also made a suds of one teaspoon t'ul of
soft soap to one pint of water. With each of these I wetted 25 cabbage
plants, and placed a Cut-worm in the ground near the stem of each.
This was done a week since, and I have had none of these cut yet, and
they continue to be cut in a field of 14 acres near by. The owner has
only saved this lot of cabbages by keeping boys constantly searching for
and killing the grubs around the plants and occasionally transplanting.
I also tried a plan of former days, by putting a little freshly slacked
sifted lime around 115 plants, with this exception, that in order to make
the test good I buried 12 Cut-worms, about one-half inch deep, and from
one to two inches from the stems of each of a dozen plants. I have seen
them every day for more than a week, and I have not found one plant cut
yet. I have also tried the effect of these infusions on the Sing {Selandria),Sb
small solt-bodied caterpillar I found on pear and cherry trees. Syringed
the branches, and wetted them weU. The stramonium water was the
most powerful ; seemed to kill at once, but next day I found many yet on
the leaves. I then gave them a dusting of lime powder, and that com-
l)letely banished them.

I formerly used a powder of ailanthus and also of stramonium
leaves to eradicate this pest from fruit trees, but of late years I find
lime powder, well sifted and dusted on, involves less labor, and is a most
effectual ren)edy against this pest.

I find cabbage-growers in general make a great mistake by plant-

33

iiio' too deep. They pot nearly all the stem into the ground; this gives
easy access to the Cnt-worin to destroy tlie heart of the cabbage; they
wonld do much better not to plant so dee]>, especially the late-grown
kinds, as the hard stem is less liable to be cnt than the heart of the
c>abbage.

JuJij 31, 1885. — In yonr favor of the 17th instant you requested me to
continne my experiments as heretofore with infusions of Tansy, Ailan-
thns, stramonium. Mandrake root, Elder, and tomato leaves, in order
to give a definite answer as to which may be of value as an insecticide
and which are worthless. I beg leave to say I have gone to work very
willingly to try to answer this important question, and made tests on
various insects.

As most of the above plants are now easily procured, I made infusions
in large quantities, but of about the same strength as heretofore. I find
it is better to let these leaves dry two or three days before the infusions
are made. These liquids seem also to gain strength by age. At a week
or ten days old they are much stronger than when first made. One
l)ound weight of the partially dried leaves to one gallon of water makes
a good wash. I first tried the relative value of these infusions on some
brown and yellow hairy caterpillars, the larvae of a Bomb^^cid moth
(Arctia virginica), li- to 2 inches long, which had been very plenty in
this locality, on the Sunflower. I marked a certain number of plants for
each test, and sprayed and wetted both sides of each leaf thoroughly.
They all continued to eat the leaves after this as before; but with those
sprayed with ailanthus, stramonium, and mandrake not nearly so raven-
ously— they seemed rather dainty in their biting.

Next day I wetted again as before, with about the same result; but
when 1 wetted the worms thoroughly with stramonium they fell off and
crawled away, and seemed not to ascend the plant any more.

Then, in order to satisfy myself as to the merits of the different liquids,
I collected a number of these caterpillars and i)laced them in six groups,
on a short piece of board. I wetted them all over equally. They were
all able to crawl out of their bath; but, when I i)ushed them back and
wetted their heads, they did not get out again from either mandrake,
ailanthus, or stramonium. The others crawled out of several wettings ;
but these remained on the board, and were dead next day.

About the middle of the month I sowed a patch of white turnips in
drills, for the purpose of testing these liquids on the Turnip Fly {Raltica).
They were up in about four days. I commenced wetting them; not all,
but part of each of six rows. I found it was necessary to wet them every
day for a week, and afterwards two or three times, before they got
ahead, in order to keep down this pest ; and where I did not wet them
they were all eaten off" in about seven or eight days, and I could not
say positively which of these liquids was the best.

I tried these infusions also on the Grai^e-vine Thrips, on an outdoor
arbor, and both sides of the leaves had to be wetted. In this case the
02(38— Bull. 11 3

34

stramonium and tansy seemed the best, but the leaves had to be well
drenched twice, and in some cases three times, before the insects forsook
them or were all killed.

I have also tried the effects of these washes on the Cabbage Louse
[Aphis hrassiece). These seem easier killed now than about the begin-
ning of this month. Each liquid seems to have a better hold of them
than at first, and two applications killed them all on every head to
which these washes were applied. I sprayed 12 heads, two to each

liquid used.

I also tried the power of these infusions on some cucumber vines, to
see what effect they would have on the Striped Cucumber Beetle {Gale-
n/ca), and find that unless these washes are very plentifully applied they
will have but little effect on this bug.

On the 24th of this month I procured six Cabbage Cut- worms, and pat
one near the stem of each of six cabbage plants, and placed it about
one inch under ground. I then placed a common tomato can over each
plant and sunk it in the earth about one-half its depth. I had previ-
ously cut off both ends smoothly with a pair of scissors ; then about
one-half pint of liquid was poured into the can around each plant, and
this wetted the ground, I should say, about three inches. The follow-
ing night the plant wetted with elder was cut off by its worm, and the
fourth*night, the 28th instant, another, marked ''Ailanthus,^' was cut;
but since then no more have been cut.

My object in this experiment was to find out, if possible, the real
value of each of these infusions as a preventive to the Cut-worm ; for if
some will not cut at all, after being starved, as it were, in prison, I think
that wash may be depended on.

These infusions have been taken on their merits alone, and I do say
they all have some good properties as insecticides. I do not think much
in general of tomato leaves, nor Elder alone ; nor do I think Mandrake
will ever become popular, from the tact of the extra labor and difaculty
of collecting and preparing it. Tansy, Ailanthus, and stramonium are
the best, in my opinion, and of these three stramonium stands the high-
est in mv estimation.

I have to thank Professor Riley very much for assistance rendered
in determining the species of many insects in these and many other
tests performed by me.
Most respectfully,

THOMAS BENIs^ETT.

Professor C. Y. Riley,

Entomologist., &c.