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Bulletin No. 1 1— New Series.

U. S. DEPARTMENT OF AGRICULTURE.

DIVISION OF ENTOMOLOGY.

S

THE

GIPSY MOTH IN AMERICA:

A Summary Account of the Introduction and Spread of Porthetria

dispar in Massachusetts and of the Efforts Made by

the State to Repress and Exterminate it.

I.. ( ). HOWARD.

ENTOMOLOGIST.

WASHINGTON;

GOVERNM E NT I ' K 1 \ l' 1 \ < , Ot V 1 I K

1 S 9 7 .

Bulletin No. 1 1— New Series.

U.S. DEPARTMENT OF AGRICULTURE.

DIVISION OF ENTOMOLOGY.

THE

GIPSY MOTH m AMERICA

A Summary Account of the Introduction and Spread of Porthetria

dispar in Massachusetts and of the Efforts Made by

the State to Repress and Exterminate it.

L. ( ). IK IWARD,

ENTOMOLOGIST.

WASHINGTON:

(. I l v KB N M I". \ T PRINTING 0 W F I I B

1 89 7.

LETTER OF TRANSMITTAL

TJ. S. Department of Agriculture,

Division of Entomology,
Washington, D. C, November 30, 1897.
Sir: I have the honor to submit for jmblication an account of the
Gipsy Moth (Porthetria dispar) in Massachusetts and the efforts which
the State has been making to exterminate it. This report has bee ;
prepared in accordance with a provision made in the appropriation
bill for this Department for the fiscal year ending June 30, 1898. I
recommend it for publication as Bulletin No. 11, new series, of this
division.

Respectfully,

L. O. Howard,

Entomologist.
Hon. James Wilson,

Secretary of Agriculture.
2

CONTENTS.

Introduction : Reasons for this publication 5

The Gipsy Moth in Europe 6

Life history of the insect 6

Appearance <>f the Gipsy M<>th in America 7

A review of the State legislation 9

Methods used by the State authorities 14

Opposition to the State work 22

The investigation of the work by the writt-r duri

Present condition of the infested territory 24

Conclusions

ILLUSTRATIONS.

Fig. 1. Female Gipsy Moth 5

2. Male Gipsy Moth 6

3. Full-grown caterpillar of Gipsy Moth 7

4. Pupa of Gipsy Moth .' 8

5. Map showing the territory actually infested by the Gipsy Moth, as

determined in 1891 by the State board of agriculture, and the areas
supposed to be infested in 1889 and 1890 10

6. Map showing the region found infested in 1891, the colonies of the

Gipsy Moth found since 1891 (but prior to 1896) outside that region,
and the three principal centers of infestation and distribution in
the woods 11

7. Manner of applying burlap bands 18

8. Map of the territory found infested in 1891, showing the relation of

the distribution of the Gipsy Moth to population 25

4

THE GIPSY MOTH IN AMERICA.

INTRODUCTION: REASONS FOR TIIIS PUBLICATION.

As almost everyone has learned through the publications of the
State Board of Agriculture of Massachusetts and through the news
paper press, the Gipsy Moth of Europe was some years since acci-
dentally introduced into the State of Massachusetts, nourished there
to an alarming extent, and became as early as 1890 the subject of State
investigation. Since 1890 large sums of money have been expended
in the effort to exterminate the insect. All of the work has been done
under State authority and with State funds. Outside entomologists of
standing have occasionally been called in to advise the persons charged
with the work, and in the
winter of 1894-95 an un-
successful attempt was
made to secure aid from
the National Government.
In fact the United States
Sen ate inserted an amend-
ment to the appropriation
bill for the Department
of Agriculture allotting
$40,000 for the purpose,
but this amendment was
not accepted by the! louse

of Representatives and was eliminated in conference committee. In
the session of Congress of 1896-97, however, a clause was added to
the section making appropriations for entomological investigations
under the Department, providing for u an investigation into the ravages
of the Gipsy Moth." In conformity with this provision an investigation
was duly undertaken in this division. This investigation lias included
a study of the extent and character of the ravages of this pest and of
the remedial measures used by tin4 State officials of Massachusetts,
with the object in view of deciding upon the best course to pursue in
the future. The insect is at present confined to eastern Massachusetts,
and it is highly desirable not only to limit its spread, but also to
exterminate it. if possible, in the territory already occupied.

Fig. 1.— Female Gipsy Moth— natural siie (from Tnatet Lin).

THE GIPSY MOTH IN EUROPE.

Porthetria dispar is an old and well-known European insect. It occu-
pies the whole of central and south Europe, flourishing in temperate
regions and extending its range across temperate Asia to Japan. It is
found as far south as Algeria, into which country it is supposed to have
been introduced in comparatively recent years, but does not abound
in England, and, in fact, is a very rare species in that country. In
portions of France, Germany, and Eussia it is considered to be an
injurious insect of first-class importance. In the protected forests of
these countries its ravages are occasionally excessive, while at frequent
intervals the shade trees of the larger cities are completely stripped
of their leaves. Few European insects have received more attention
from the European foresters than this species. Books published as
early as 1720 refer to its ravages. Judging from the European liter-
ature it does not appear in equal numbers every year, but will be

excessively abundant in a certain region
for two or three years in succession,
and will then remain in comparative
obscurity for several years, just as is
the case with other noxious species, not
only in Europe, but in this country as
well.

So far as can be learned no large scale
remedies have been adopted in Europe.
The intermittent character of the appearances of the insect in injurious
numbers render remedial work necessary only at intervals. Aside from
removing the egg clusters by hand, trapping the caterpillars with bands,
and preventing their access to uuinfested trees by means of sticky sub-
stances, no remedies worthy of detailed consideration have been adopted.

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Fig. 2.— Male Gipsy Moth— natural size
(from Insect Life) .

LIFE HISTORY OF THE INSECT.

All through its European range the Gipsy Moth has but one annual
generation, and this statement applies equally well to Massachusetts.
The eggs are about one-twentieth of an inch in diameter and are laid
in clusters, each cluster containing from 400 to 500 eggs and varying in
size from one half to one and one-half inches in length and from one-third
to one inch in width. Each cluster is covered with yellowish hairs from
the body of the female moth, causing the cluster to resemble a bit of
sponge in general appearance. These clusters are attached to the trunks
of trees, to stones, to logs, and in all situations which can be reached by
the females. The females have an especial propensity for crawling into
crevices, thus frequently concealing their egg clusters from casual obser-
vation. The eggs are laid in the latter part of summer and the insect
remains in the egg state for nine or ten months. The caterpillars hatch
from the end of April until the middle of June, reach full growth in
the course of about ten weeks, spin flimsy cocoons attached usually to

the trunks of the trees, and within these cocoons transform to chrysa-
lids, remaining in this stage from ten to thirteen days, and emerging
as moths in late July or August.

The feeding of the caterpillars is done as a rule at night, except
when they occur in very great numbers, and they arc known to destroy
the foliage of nearly every native and introduced plant of economic
importance. During the first few weeks they remain most of the time
on the leaves feeding on the under surface, but as they grow larger
they crawl down the branches and the trunk toward the ground in the
early mornings, and there seek protection under loosened bark or in
cracks in the trunk or quite at the ground under leaves and rubbish,
ascending again at nightfall to resume work upon the foliage. Upon
this habit depends one of the best remedies,
that of trapping the insects under bands, but
also upon this habit depends possibly the
main means of distribution of the species.
The activity of the caterpillar is responsible
in large measure for its spread.

The adult insect, or moth, although possess-
ing what seems to be abundant wing surface
in both sexes, Hies readily only as a male. The
female possesses such a heavy body that her
aerial locomotion is limited to a tew strug-
gling flaps which result simply in lessening
the force of her fall from a height. A female
issuing from a cocoon high up on the trunk
of a tree and falling from this cocoon, some-
times before laying her eggs and sometimes
afterwards, is seldom able by the use of her
wings to reach the ground at a greater distance
than a few yards from the base of the tree.

Many natural enemies of the Gipsy Moth
are known in Europe. The writer has listed
28 species of hymenopterous parasites. Several dipterous species are
also known to attack it, and many predatory insects as well as birds
and other animals. Diseases of a bacterial or fungus nature fre-
quently carry it off in large numbers, as is frequently the case with
other caterpillars, both in Enrope and in America.

APPEARANCE OF THE (ilPSV MOTH IN AMERICA.

Fig. 3. — Full-jrrown caterpillar of
Gipsy Moth— natoral Bise tt'n>m
Life).

Through the efforts of the persons having the Massachusetts work
in charge, it lias been practically decided that this insect was first
brought to the United States by Prof. L, Trouvelot. a naturalist and
astronomer, in 1869. Professor Trouvelot was at that time connected
with the astronomical observatory at Harvard University, and tor his
pleasure and interest was engaged in the study of wild silkworms with

8

the idea that species of commercial value might be found, and that per-
haps something might be done in the way of cross breeding allied
species, thus producing not perhaps a better quality of silk than that
of the silkworm of commerce, but a hardier insect, which would
require less artificial attention and at the same time would be more
resistant to disease. The whole experimentation, we believe, was sug-
gested by the disastrous prevalence in the silkworm establishments of
Europe of the pebrine disease, which some years later was controlled
by virtue of Pasteur's discoveries.

In the course of this work Professor Trouvelot brought over from
Europe living specimens of different silk-spinning caterpillars in differ-
ent stages of existence. Among others he imported living egg clusters

of the Gipsy Moth. He lived at No. 27
Myrtle street, Medford, and the insects
escaped from his window into the adjoin-
ing garden. One story is that the eggs
blew out of the window, and another that
the caterpillars crawled out. He seems,
however, to have done what he could to
repair the damage, gave public notice of
the escape of the species, and undoubt-
edly searched carefully for the missing
eggs or larvre. Unfortunately, the part
of Medford in which he lived almost
immediately adjoined an extensive wood
lot, densely covered with underbrush,
and in this jungle of vegetation the in-
sect soon established itself. For many
years, however, it was not noticed by
the citizens of Medford, from which it
is plain that it increased with extreme
slowness. The principal reasons for this
slow increase are supposed to be, first,
that the insect was gradually accommodating itself to the severe cli-
mate; second, that the wood lot abounded with insectivorous birds,
and, third, that almost annually it was burned over. That there was,
however, a constant, though slow, increase is shown by the fact that
after twelve or fifteen years the caterpillars began to be troublesome
in the gardens of the residents of that portion of the town.

They fought it vigorously and undoubtedly retarded its increase by
their individual activity, but by the summer of 1889 it had multiplied
to such an extent as to become a notorious pest. In that summer its
numbers were so enormous that the trees were completely stripped of
their leaves, the crawling caterpillars covered the sidewalks, the trunks
of the shade trees, the fences, and the sides of the houses, entering the
houses, and getting into the food and into the beds. They were killed

Fig. i Pupa of Gipsy Motli

size (from Insect Life)

-natural

9

iu countless numbers by the inhabitants, who swept them up into piles,
poured kerosene over them, and set them on fire. Thousands upon
thousands were crushed under the feet of pedestrians, and a pungent

and filthy stench arose from their decaying bodies. The Dam
were so gTeat that in the still summer nights the sound of their feed:
ing could plainly be heard, while the pattering of their excrementaJ
pellets on the ground sounded like a shower of rain. Valuable fruit
and shade trees were killed in large numbers by their work and the
value of real estate was very considerably reduced. So great was the
nuisance that it was impossible, for example, to hang clothes upon the
garden clothesline, as they would become covered with the caterpillars
and stained with their excrement. Persons walking along the streets
would become covered with caterpillars spinning down from the b
To read the testimony of older inhabitants of the town, which has
been collected and published by the Gipsy Moth committee, reminds
one vividly of one of the biblical plagues of Egypt.

During all this time the Medford people had been under the im]
sion that the insect which they were fighting in their gardens was a
native species, and they knew it simply as "the caterpillar" or "army
worm." There seem to have been no local entomologists, and no one
appears to have taken the trouble to find out definitely what the insect
might be. In June, 1889, Mr. John Stetson took a specimen to lion.
William E. Sessions, secretary of the State board of agriculture, for iden-
tification. The insect was new to Mr. Sessions, who advised .Mr. Stet-
son to send it to the State Agricultural Experiment Station at Amherst.
This was done, and in the absence of Professor Fern aid in Europe, his
wife, who is fortunately a learned entomologist herself, was able, after
searching through the European books, to identify the insect as the
larva of the well-known Gipsy Moth of Europe. The fact was immedi-
ately announced through the newspapers, and the writer, together with
many others, gained his first knowledge of the occurrence through the
"New England Farmer" of July 13, 1889.

A REVIEW OF THE STATE LEGISLATION.

The tirst combined effort to check the caterpillar was immediately

undertaken. A town meeting was held on July L5, 1889, and the sum
of $300 for the care of shade trees was appropriated, to be expended
under the direction of the road commissioners. Men were employed to
scrape off the e^^x clusters from shade trees, and much money and effort
were expended by citizens on their own premises, in November an
illustrated bulletin was issued, in an edition iA' 15,000 copies, by Profi
Fernald, at the State Agricultural Experiment Station. It was mailed
to taxpayers in Medford and vicinity, and was printed in full in one of
the local papers of December 6, It was found during that winter that
the insect was SO DUmerous and SO widely distributed that the town
authorities could not successfully tight it and the legislature was

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therefore petitioned for an appropriation. Governor Brackett men-
tioned the outbreak in his message to the legislature, and as a result
the joint committee of agriculture visited Medford and saw the masses
of egg clusters on the trees. Finally an act appropriating $25,000 was
passed. The act provided for the appointment of a commission of three
persons to take charge of the work. Inspection work was at once
undertaken to determine the extent of the region infested, and this
inspection resulted in the establishment of the fact that the moth
occurred over a much larger section of the country than had been sup-
posed, and as a result an additional appropriation of $25,000 was made
early in June.

In February, 1891, the first commission was removed by Governor
Eussell and a second one appointed. The first commission had been
salaried and the second served without remuneration. This commis-
sion was superseded after a few weeks by the State Board of Agricul-
ture, on their own recommendation, and in April an act was passed
authorizing the board to carry into execution all reasonable measures to
prevent the spread and secure the extermination of the insect. Unex-
pended appropriations were placed at the service of the board, and on
June 30 an additional appropriation of $50,000 was made. A map of
the infested region was the first work of the State board, and it was
soon found that previous surveys had by no means indicated the com-
plete distribution of the insect. In fact, the infested area, as it was
supposed to have been determined in 1890, was at once enlarged by
this new survey to at least five times its former size. The comparative
estimates of 1889-90-91 are indicated on the accompanying map (fig 1).
The survey of 1891 has been practically the basis of the work ever since
that time, and it is interesting to note that, although a few colonies
were soon after found in Danvers, Burlington, and South Boston, but
three localities of infestation have since been found outside of the
boundaries then laid down. These localities, in Brookliue and Lincoln,
will be mentioned in a later parn graph.

The organization of a competent field force was then begun and a
detailed system of work was decided upon. Professor Fernald, of the
Agricultural Experiment Station, was appointed entomological adviser
to the subcommittee of the board in charge of the work. In January,
1892, the committee recommended an appropriation of $75,000 for the
continuance of the work, and an act authorizing this appropriation was
passed on March 1. An attempt was immediately made to destroy all
egg clusters found on the roads in order to prevent the spread of cater-
jfillars, and after the eggs had hatched, spraying operations were begun
against the young caterpillars and the method of burlaping the trees
was introduced against the larger larvse. The appropriation was not
sufficient to provide enough men to thoroughly examine the burlaps,
yet during the summer the officers reported that nine-tenths of the
insects in places known to be infested had been killed, and in many

13

localities they had been exterminated. During the fall of this year an
attempt was made to thoroughly search the country, but the lack of
money was felt, and it was found necessary to discharge a large part of
the force. In its annual report the committee requested an appropria-
tion of $165,000 for the work in 1893. Instead of this sum, however,
an appropriation of $100,000 was made on April 12, and field work was
at once begun. An increased force was put at work, and in general
the same methods were adopted as had been used the previous year.
At the close of this season an appropriation of $165,000 was again
recommended to the legislature, and again the amount was reduced by
the legislative body to $100,000, and this was not secured until May 23,
when more than three weeks of the best working time of the season
had been lost.

Full inspection this year revealed the presence of the insect in several
localities not before known to be infested. This time an appropriation
of $200,000 was asked for by the State board of agriculture. This
proposition developed some opposition, and public hearings were held,
and the legislative committee on agriculture finally resolved to call
for an appropriation of $150,000, which was granted on May 17, 189.1.
Again valuable time had been lost, but work was immediately begun
and carried through the season. In the winter of 1895-96 the board
of agriculture recommended an appropriation of $200,000 for work
during 1896, and also urged that the appropriation be promptly made
in order to avoid the hindering of the spring work. An emergency
appropriation of $10,000 was granted and became available April 28,
but only $100,000 was granted for the work for the season of 1896, the
remaining $90,000 becoming available June 1, too late, as the officials
say, to carry out the plans made for the season's work, and necessitating
a complete change in plans. Extra work was also made necessary by
the hatching of the eggs which it had been planned to destroy in the
spring had the appropriation been avadable at that time. The small
amount of the appropriation would not admit of exterminative work
over all of the infested territory, and in order to prevent the spread
the outer towns were closely attended to through the season.

Two colonies were discovered this year in Brookline, just outside of
the previously known infested territory. The discovery of these outside
colonies, however, did not indicate any recent spread of the moth, as
conclusive evidence existed that they had been established for a number
of years, but had not been reported to the committee and had not been
discovered by its inspectors.

In December, 1896, an appropriation of $200,000 was asked for work
during 1897. On January 19, 1897, an advance of $8,333 R as made, and
a balance of $141,667 was made available February 26, making the
appropriation for the year $150,000. The committee was thus enabled
for the tirst time to begin work early in the season, and the results
accomplished during the year 1897 have greatly exceeded in value those
of any previous year.

14

METHODS USED BY THE STATE AUTHORITIES.

After the preliminary inspection work mentioned in the previous sec-
tion had been largely accomplished, methods of actual destruction of
the insect were adopted. In the course of the eight years during which
this work has been carried on, there has been a steady improvement in
the efficacy of the insecticide measures used. For a time these methods
consisted almost entirely of the destruction of the egg masses, spraying
with arsenical poisons for the caterpillars and killing the caterpillars
under burlap bands on tree trunks, and these measures are to-day prac-
tically the only ones used where colonies exist in towns or on cultivated
grounds. During the past two years, however, work has been carried
on with great energy in forest lands, and here the means mentioned
have been supplemented with extensive clearing out of underbrush,
thinning out of the woods by the felling of a certain proportion of the
timber, and by burning over the ground. When the writer first visited
the infested region in the summer of 1894 the earlier methods only
were in use. Nevertheless a number of original methods had been
adopted, and he was impressed, as everyone has been who has thor-
oughly investigated the work of the State officials, with the systematic
and thorough manner in which the remedial work was being carried on.
He had nothing but praise for this work, and the only obstacle to the
entire success of the effort which he foresaw was the occurrence of the
insect in islands throughout large stretches of densely wooded country,
where the methods then in use could hardly be completely effective.
He did not anticipate the possibility of such radical woodland meas-
ures as have been instituted. But of this more will be said in a later
paragraph.

The conspicuous color of the egg clusters and the long duration of
the insect in this stage of existence, together with the fact that the
destruction of an egg mass prevents much potential damage, very early
suggested to the officials the feasibility and importance of fighting the
insect in this stage. Indeed, one of the first measures adopted by the
selectmen of Medford was the collection of egg clusters from the trunks
of shade trees in the infested district. Moreover, it seems that this is
the principal remedial measure adopted in Europe.

The great success, however, which had attended spraying operations
against other leaf-feeding caterpillars in the United States caused cer-
tain economic entomologists to believe that the labor of collecting these
egg clusters during the winter time was unnecessarily great, and that
there would be much economy both in labor and money in waiting until
the eggs hatched in the early summer and then spraying the surround-
ing vegetation with paris green or london purple. In fact, this argu-
ment was put forward very strongly by Professor Riley in his testimony
before the State legislative committee on agriculture in Boston, March
4, 1891. It soon developed, however, that the Gipsy Moth caterpillar
was unusually immune to the effects of arsenicals; that trees sprayed

15

with the arsenicals, even if used at a strength sufficient to burn the
foliage, would support .these caterpillars without destroying more than
a small proportion of them.

Efforts were therefore made to discover an arsenical compound which
could be applied to trees at a strength considerably greater without
burning the leaves. These efforts were successful, and the substance
known as arsenate of lead was developed and is coming into general
use, not only against the Gipsy Moth, but against other leaf-feeding
insects. This substance may be sprayed upon the tenderest foliage at
a dilution of 10 pounds to 100 gallons of water without injury, whereas
1 pound of paris green to 100 gallons of water frequently injures the
leaves. Even with this valuable arsenical combination (the discovery
of which, it must parenthetically be stated, has already proved of the
greatest value to the economic entomologist) it was found that except
under certain conditions spraying could not be generally adopted with
perfect effect against the Gipsy Moth. A certain proportion of the
caterpillars on sprayed trees always escaped, so that it can not be abso-
lutely relied upon for exterminative work.

Moreover, extensive experimental work has shown that there is only
about one month in the year during which effective spraying can be
done. This is from about the 15th of May. when most of the caterpil-
lars have hatched, to the loth of June, when ail have hatched, and
when most of them have reached the age when they will cluster under
the burlap. If, during this short period, there are two or three weeks
of rainy weather, as is frequently the case, very little effective spraying
can be done. Furthermore, a concentration of the work in this short
season makes necessary a great expenditure for spraying apparatus,
and necessitates the employment of a large force of men tor this pur
pose — a difficult matter, since proper spraying requires expert hands.

The conditions under which spraying is still carried on and undei
which it is the only practicable remedy, are such as exist in certain
parks — franklin Park, for example, where there are extensive stretches
of tangled vines and valuable shrubbery which hide the egg masses
and which can not be banded, and which, at the same time, on account
of their value, can not be burned over. Here spraying is still carried
on, and with good effect, owing to repeated operations and great per-
sistence, which, of course, involve a very considerable expense.

Different methods of egg destruction have been tried. The first
recommended was to the effect that the eggs be scraped from the I
and burned. They were scraped off or cut away from the trunks on
which they rested, placed in tin cans, and burned in stoves or brush
tires. A tierce heat is required for their destruction. Whenever the
eggs were very numerous in undergrowth or waste land, tire was run
over the dead leaves and debris as an experiment, but this method
seemed to have but little effect, as the heat was not sufficiently intense.
The hairy cover seems remarkably noncouductix e and renders the

16

impervious for a time to sudden heat. Some minutes are required to
destroy them utterly. An ordinary brush fire merely scorched the
outside layer and killed a few of the outside eggs. Next, experiments
were made with crude petroleum, spraying it over the ground and
igniting it, but this was not perfectly effective. Continued experi-
ments were made with different methods. A remarkable apparatus
was constructed to distribute inflammable oil in a spray which devel-
oped wonderful combustive powers. Many substances, both liquid
and gas, were experimented with to destroy the eggs, and a series of
interesting implements were invented in the way of hand mirrors to
assist in searching for the eggs, and knives. and scrapers for removing
them and destroying them.

It resulted from this experimental work that creosote was found to be
the best substance for egg destruction, and the present method consists
in thoroughly painting each egg mass found with a cheap creosote oil.
There are great difficulties in the way of economically and rapidly apply-
ing this remedy. The eggs must be searched for in inconceivable crev-
ices, trees must be climbed and egg clusters, which can not be reached
by hand, must still be painted by means of brushes attached to the
extremities of long poles. The process, however, is carried on very
effectively and much more rapidly than would be supposed. The men
employed have become so trained in the discovery of eggs that they
will see them instantly, even at the tops of tall trees, where they would
be entirely unnoticed by nonexperts. A gang of men will proceed
rapidly through a bit of woodland, treating the egg clusters in this
way, and it is safe to say that after they have finished, and after the
still keener eyed inspectors have followed up, the number of potential
caterpillars has been reduced to a minimum.

After the eggs have hatched, the new method of work is at once
introduced. According as conditions vary in different localities the
director of field work has varied his method of treatment. Thus, in the
case of some colonies where the eggs were numerous, but concentrated
within a comparatively small space, it has been considered advisable
to allow them to hatch, and the work of destruction has in such cases
been directed exclusively against the caterpillars. Where, however,
the egg masses were more or less scattered, every effort has been made
to prevent the appearance of the caterpillars by destroying the eggs.
Against the caterpillars themselves several kinds of work have been
carried on — the spraying previously mentioned and two methods of
banding the trees. The first consists in placing around the trunk of
the tree a viscid sticky band, either tar paper or fish oil, or the sticky
German product known as a raupenlehn " (caterpillar glue), applied
directly to the bark. This substance, which has been used with good
effect in Europe against the Gipsy Moth caterpillar and against the
even more numerous and destructive larva of the nun moth, remains
viscid for many months, and is very effective for the purpose for which

17

it is used. The object of this sticky band is to prevent the ascent of
the tree by young caterpillars batching from egg masses at or near the
surface of the ground. Extensive experiments and considerable prac-
tical work have been conducted with bands of this character in the
course of the fight, but their use at present is not great, the officials
concentrating their efforts in the main upon other mean-.

These sticky bands, however, are still used in one rather important
connection. In forest work, where the eggs npon the trees have
already been treated with creosote in the fall, the undergrowth cleared
away, and the dead limbs burned, the colony is abandoned for the
winter. Just before the time of the hatching of the caterpillars in the
spring the sticky bands are placed around the trees and thus prevent
the comparatively few caterpillars which may hatch from egg masses
laid in hidden and undiscovered places at the surface of the ground,
such as deep crevices between rocks, from ascending the trees. Thus.
when all of the eggs have hatched, the remaining caterpillars can easily
be destroyed by burning the ground over with a very ingenious and
destructive apparatus, which has been invented in the course of the
work, and which is known as the "cyclone burner."

The second band is used to entrap caterpillars which have already
made their appearance in a given tree or the presence of which is sus-
pected. After much experiment, the committee has adopted a simple strip
of common burlap, which is tied about the tree with a single string at its
middle, at about the height of a man's shoulders. The burlap is pur-
chased in bales and cut into strips 12 inches wide. These strips are made
into rolls, which the workmen carry suspended from the shoulder.
Approaching the tree, the roll is passed around the trunk and enough
cut off to encircle the tree and lap sufficiently at the ends to allow for
shrinkage. A bit of twine is tied around both tree and cloth at the
middle of the latter. The upper half of the burlap is then turned down
over the twine, thus making a double band about the tree. The object
of this banding is to assemble the caterpillars which may be upon the
trees, since it has been found, as stated in an earlier sentence, that the
larva* feed at night and descend the trunk in search of hiding p!
during the day. Where the trunk and branches offer no better hiding
places, most of the caterpillars will crawl down morning after morning
and seek the shelter of the burlap. The men in making their rounds
raise the burlap and cut or crush the caterpillars collected beneath it.

Many little details connected with the systematic examination (^' the
burlap can not be touched upon, but it will suffice to say that tin' force
at the disposal of the committee is so organized and the system of
examination is so arranged that this method becomes a very effective
and by no means so expensive a measure as might be supposed for
destroying the caterpillars. Down to L897 it was found that sooner or
later practically all, in fact. 1 may almost say positively all, oi' t he cater-
pillars in a given tree seek shelter under the burlap band except dur-
S!»;,7_Xo. 11 ^

18

ing very rainy weather. It will readily be seen that it is not at all
necessary to examine the bands every morning, since the life of the
caterpillar extends through several weeks, and examination at inter-
vals of a number of days will thus suffice. So effective has this method
of ridding the tree of the insect proved that one of the most experi-
enced and efficient of the assistants in the work has told the writer
that it is his firm opinion that the last Gipsy Moth larva in the State
of Massachusetts will be caught under a burlap band.

Very much to the surprise of the workers, it was found that with the
season of 1897 the caterpillars changed their habits to some extent, and
that they sought the protection of the bands during the day with much
less regularity than in previous years. It seems likely that this is to
be accounted for by the fact that the breeding season of 1897 was an
exceptionally dark and rainy one. The effort of the caterpillars in

entering beneath the bands seems to have
been for the purpose of avoiding the
bright sunlight, so that when the sky
was dark there no longer existed a neces-
sity for this effort. The fact remained,
however, that the bands were by no
means as effective as they had been in
previous years, and the workers were
obliged to adopt a modification of the
former methods. The extensive banding-
was done as usual in the spring, but the
changed habit becoming apparent more
spraying was carried on, and it was found
that with the smaller trees a severe jar
would cause most of the larvaj to fall to
the ground, more or less suspended on
their journey by silken threads. Upon reaching the ground they at
once crawl actively to the base of the tree, where, entering the burlap
band at a height of 4 or 5 feet, would creep under it, and were thus
in condition to be destroyed by the next gang of men. This jarring
method was adopted with great success in several bad colonies.

Toward the end of July, however, the weather changed radically.
The long-continued spell of wet weather ceased and the caterpillars, to
a certain extent, at least, resumed their normal habits and came to the
bands 5 but by this time the examining of the bands had practically
been discarded. They served a most excellent purpose, however, since
in many localities perhaps the majority of the egg clusters were laid
beneath them or in their immediate vicinity. Several badly infested
regions were visited for example on the morning of November 17, in
which it was noticed that almost every egg cluster on a given tree was
to be found within a circle of a few inches from the band. This renders
their treatment particularly easy, since the less expert men could be
used for the work.

Fig. 7. — Manner of applying burlap
bands : a, band as originally tied ; b,
band with upper half turned down-
greatly reduced (after Forbush).

19

In the banding work it was soon found that the burlaps were most
successfully used on well-kept trees with smooth, round trunks and
branches. If the trees were originally in such condition or were first
properly prepared, the insect was eradicated from many localities by
the banding method alone, but when trees with decaying blanches,
hollow trunks, or rough or loose bark become infested the caterpillars
frequently prefer the shelter afforded by such cavities or inequalities
to that afforded by the burlap. As a result, the employees in placing
the burlaps upon the trees throughout an infested region were obliged
to prepare the tree in many cases. Dead branches were cut off, cavities
were filled up or covered tightly with tin, and the rubbish and weeds
were removed from the ground about the tree. This work was onerous
and consumed much time, but it paid in the long run not only by bring
ing about the ready destruction of the worms under the burlap, but by
greatly improving the health and appearance of the trees. The writer
has seen many trees whose lives were undoubtedly saved by this sani-
tary treatment by the gipsy-moth workmen.

Experimental work was carried on sufficiently against the pupae
within their cocoons and against the moths to show that economic work
against the insect in either of these stages could not be as successful as
in other stages, although as a matter of fact thousands of the pupae
and moths are incidentally destroyed each year.

We have thus mentioned the mam methods used against the insect
in any one of its specific stages of life. Quite as important, however,
has been the general work of the committee in the wa}r of clearing up
the breeding places and rendering the localities swarming with large
colonies of the moth uninhabitable by them, or at least easy to treat
successfully. Rubbish heaps have been cleaned up and neglected door-
yards, pasture lots, and waste lands have been thoroughly renovated
or burned over. The general work, however, which has been carried
on in the woodlands has been still more arduous and important. Any
one visiting certain places in the Middlesex Fells or in the Lynn woods
Park or any of the dense forest areas lying to the northeast of
Boston, would be apt to say that an extermination of any species of
insect in such jungles of vegetation would be impossible, aud perhaps
so it would were the Gipsy Moth scattered generally through this
region, as seems to be the prevalent impression. Few people who have
not visited the locality realize the character or extent of the woods in
the outlying (owns of Melrose, Lynnfield, Peabody, Med ford. Stone
ham, Wakefield, Saugus, Woburn, Winchester, and Lexington.

Although the country is very thickly settled — so much so that in
driving along many of t lie roads one seems to be almost traversing a
continuous village — yet standing upon some point of vantage like
Castle lvock or Bear Hill, the whole country for miles around has almost
the appearance of a virgin forest. The Gipsy Moth, however, is not
generally distributed throughout this region, but occurs here and
there — frequently at great intervals— in isolated and restricted spots, to

20

which the workers have given the name colonies or groups of colonies.
It is therefore unnecessary to work through hundreds of acres of wood-
land, but only here and there through patches of comparatively few acres.
This distribution is readily accounted for by the fact that the insect
spread from a common center in Medford, not by the flight of the moth,
for the moth does not fly, but by caterpillars being carried upon the
clothes of pedestrians, and upon buggies, market wagons, carts, and
other vehicles, and crawling off again at some stopping place perhaps
miles from the original center. This had been going on for years before
the State work was begun.

Wherever circumstances favored the production of a female moth at
one of these stopping places of the caterpillars and a male moth was at
a near enough distance to allow it to fly to the female and fertilize her,
there a colony was apt to be started the next year by the larvae hatch-
ing from the consequent batch of eggs. Of course, many such addi-
tional colonies proved abortive and died out, but many others continued
to propagate and to gradually spread, although very slowly. At the
same time, however, when they had become of a certain size, they were
again centers of distribution in the same way. Owing to the slowness
of natural spread of the insect, very few of the colonies, so called, are
of any great extent, so that by stamping out one here and one .there
and a third in some other place, a considerable extent of woodlands
can be rid of the insect. Moreover, on account of the vastly less fre-
quent traffic through woodland regions, the colonies are by no means
as widespread and are in almost every case to be found in the immedi-
ate vicinity of the traversing roads.

In the case of these woodland colonies the committee at once realized
that the work was very difficult and would have to be of the most
thorough character, and in the carrying out of work of this thorough
character, much opposition from the owners of the lands was antici-
pated. Such opposition has been found in some cases, while in others
the committee has been agreeably surprised to find that the gravity of
the case has brought about a disposition to permit almost any kind of
extermmative work.

It is interesting to note that a large portion of the woodland which
the committee has been obliged to treat was not owned by individuals,
but belonged to the parking systems of the different towns. In a way
this has facilitated the work of the committee, since they have been
enabled to treat in such cases with one body for a large area; but in
another way it has proved something of a hindrance, since the parking
people have, in general, been less complaisant than individual owners.

Owing to the great desirability, and in fact the almost absolute
necessity, of avoiding popular opposition, the committee has been loath
to use the powers conferred upon it by law in the way of forcibly enter-
ing premises and carrying on the necessary work. It has much pre-
ferred to adopt the conciliatory measures of enlisting the owner's

21

sympathy and support by allowing the necessity of the work and reduc-
ing his loss to a minimum. The first measure which they have adopted
in eradicating a woodland colony is to thin out the timber. This lias
been done in some places much more radically than in others. One
extensive colony in the vicinity of Woburn it was thought could not
be exterminated without the destruction of the entire timber growing
upon a certain hill, and this was done.1 In other cases about every
third tree was cut down and its stump cut close to the ground; in still
others, about half of the trees were thus felled, and in other cases only
every third tree was left standing. In one exceptional case five-sixths
of the trees were felled. The wood, as a measure of economy, was
naturally saved in every case.

Practically no timber trees have been felled. Only very rarely has
one been found which it has been necessary to cut. The poorer and
smaller trees were invariably chosen, and these were cut up into cord
wood and hauled away, and thus became a source of some recompense.
After the thinning out, the underbrush was all cut down and the sur-
face of the ground thoroughly burned over, the egg clusters upon the
remaining trees being destroyed with creosote, and the trees themselves
given a raupenleim band in the spring, burlaped where necessary,
and watched through the ensuing seasons until satisfactory evidence
was gained that the colony was exterminated. In many cases the actual
value of the timber patch has been raised by the treatment given it by
the gipsy moth people. The woods have simply been opened up to some
extent, allowing more sun to enter and better growth on the part of the
timber trees through the destruction of poorer soil exhausting vegeta-
tion, while the sale of the firewood saved has been a profit to the owner
of the land. In other cases, where the felling lias been more extensive,
the wood saved has been in the nature of a compensation rather than
a profit. In certain cases, where owners remained obdurate, men witli
ready funds and more complaisant dispositions have been found who
purchased the land and then permitted the work as a strict business
venture. In still other cases,there was no ultimate intention of preserv-
ing the woods, and the clearing of the land by the committee has simply
saved the owner the expense of doing it himself, and enabled him to
carry out at once his plans of putting the land into cultivation or cut-
ting it up into building lots.

'The exact steps taken in this operation were as follows: "The caterpillars
appeared in the summer of 1895 iu sufticienl numbers to strip the Leaves from the
I lees on two areas of an acre or more each, and it was found that they had scattered
over some 15 acres in the immediate vicinity. All of thetives (largely oaks \o to 60
feet in heighl ) and the undergrowth of nearly 10 acres were burned, and the r» si of
the wood was cut and Bold. The leaves \\ ere taken ap and burned in the fall of L895,
and in the spring of L896 tin- ground was all hu inc. 1 over. Although this burning left
little on the land except stumps and ashes, a tew oaterpillars appeared later in the

season around tin1 edges and fed tor a time on the sprouts which made their appear-
ance after the tire. Here the ground was burned over again, and no traces of the
insect have since been found."

22

By such work as this the caterpillar has already apparently disap-
peared iu a number of these dangerous woodland colonies, and the
employees of the committee claim that it has been exterminated.

A good idea of the activity of the committee and its employees may
be gained from the following statement, showing the work done during
the year 1896, and which is taken from the report of the State Board
of Agriculture, published in January, 1897 :

Work done during 1S96.

Trees (fruit, shade, and forest) :

Inspected 10, 718, 836

Found to lie infested with caterpillars, pupse, moths, or eggs 57,723

In whicn cavities have been cemented or covered 3, 408

Burlaped 567, 025

.Sprayed 4, 327

Trimmed 90, S20

Scraped 929

Cut 132,391

Acres of brush land and woodland cut and burned over 477

Buildings:

Inspected 21, 764

Found to be infested 815

Wooden fences :

Inspected 43, 917

Found to be infested 1, 318

Stone walls :

Inspected (rods) 18, 997

Found to be infested 633

Number of each form of the moth destroyed during the year by hand:

Caterpillars 1,808,105

Pupa> 441, 899

Moths .- 44,291

Hatched or infertile egg clusters 31, 501

Unhatched and probably fertile egg clusters 884, 928

OPPOSITION TO THE STATE WORK.

As has been indicated in a previous section, there has always been
more or less opposition to the passage of acts before the legislature
involving these large annual appropriations for the gipsy-moth work.
On several occasions the committee on agriculture of the legislatures
has listened to persons opposed to the work. The arguments brought
forth by such individuals have in no case interrupted appropriations,
but it is safe to suppose that some of the delays in making appropria-
tions and some of the reductions in the amount from the estimates
submitted by the State board of agriculture have resulted in part from
this opposition. The writer has made an earnest effort to learn the
grounds for this opposition. He has talked with a number of individ-
uals, some of them scientific men of high standing, but has been unable
to find a person holding opposing views who was sufficiently well
informed about the work actually being done by the committee to thor-
oughly justify the expression of a positive opinion. In the main the

23

opposition is based upon theoretical ideas, and a thorough acquaintance
with what is actually being done renders these arguments void, with
possibly one exception.
The writer was somewhat struck with the vi<-w expressed by one of

these gentlemen in regard to the influence winch the woodland work of
the committee might have upon native birds. It was said that in the
extensive partial deforestation and thorough (dealing up of underbrush
and burning over the dead leaves and low growth the nesting places
of many birds were destroyed and the birds themselves were driven
away. This seemed so important a matter that some attention was
paid to it. It will be remembered that it has already been pointed out
that none of this woodland work is general — that the insect occurs
only in isolated colonies or in groups of colonies of slight extent com-
pared with the forest area. A patch of a thousand acres of woodland.
for example, may contain two or three infested localities, none of which
will exceed 10 acres in extent, so that, admitting that the birds are
temporarily driven from their nesting places in the areas worked over.
they are not driven far and may shortly return to their original haunts.
Moreover, the workers have this very matter distinctly in view, and
they have even gone so far as to have constructed numbers of bird
boxes, which are placed in appropriate situations for the purpose of
attracting nesting birds.

Appreciating thoroughly as they do the aid that insectivorous birds
afford them in their work, they endeavor to tune, where possible, their
operations in localities where birds abound in such a way as to interfere
as little as possible with the nesting. The bird argument comes, too.
from persons living in houses with old gardens, where the birds nest in
the shrubbery. It becomes necessary sometimes to destroy this shrub-
bery in order to eradicate the moth, and. as a matter of course, the
birds are here driven away temporarily. Moreover, the workers invari-
ably break up. wherever possible, the nesting places of the English
sparrow. 80 that after all the bird argument against the gipsy-moth
work becomes unimportant.

THE INVESTIGATION OF THE WORK BY THE WKTTEK DURING 1897.

Although the writer was reasonably familiar with the conditions
existing in the infested region and the results which had been accom-
plished, as well as the methods used by the committee and the means
by which these results had been brought about, by virtue o\' two pre
vious trips to Boston in the summers of L894 and IS'.)."), as well as from
a familiarity with the published results ot' the work and from informa-
tion gained by occasional meetings with the consulting entomologist
and the director of the field work at Washington. 1>. ('.. and during
the summer meetings of the American Association tor the Advance-
ment of Science, he saw the absolute necessity for a careful investiga-
tion throughout an entire season before expressing such an opinion ot'

u

the work as that called for by the Congressional act. In order, there-
fore, that no time should be wasted, work was begun immediately upon
passage of the act, in April, although the legislation was not effective
until the beginning of the fiscal year, July 1. At the latest possible
moment before the bursting of the buds in the spring he visited Boston
and watched carefully through several days the winter work of the
committee in inspection, egg destruction, forest clearing, burning over
of ground, and preparations for summer work, making at the same time
a more or less careful round of the infested territory.

In May he again visited the headquarters of the committee in
Maiden, watched the work of this season, which consisted practically
in burlaping trees in the portions of the territory in which this
method was to be relied upon. In June the first assistant entomolo-
gist, Mr. Marlatt, who has for some years interested himself particu-
larly in the matter of insecticides and insecticide appliances, was
deputed to take up the work and carefully examine its progress and
the general conditions and to formulate an independent opinion. In
July the writer once more went over the ground, thoroughly investi-
gating the critical midsummer work of the field force, and at the same
time interviewed several persons who were opposed to the continuance
of the State work on so large a scale. In September the exped ition
was repeated, the early fall work was looked into, and additional
information gained. In November a final trip was taken for the pur-
pose of verifying all doubtful points. At this time some of the most
interesting and important work of the whole season in the way of the
wholesale destruction of the egg clusters in the Medford woodland
district about Pine Hill was being carried on. This work was studied,
other portions of the regions were visited, and a number of persons
were consulted.

PRESENT CONDITION OF THE INFESTKD TERRITORV.

As the conclusions which we may justly draw from our summary of
the work which the State of Massachusetts has done in this gipsy-
moth investigation must be based largely upon the piesent condition
of the territory in comparison with what its condition has been in
previous years, we must be more detailed in this section of the bulletin
than in others. It will be, in fact, impossible to present a satisfactory
view of the present condition without detailed consideration of the
exact facts connected with each of the thirty-two towns in the territory
in question. These are given hereafter. It must be distinctly under-
stood that while what is said under these headings of the condition of
the different localities in the previous years has not all been substan-
tiated by personal investigation on the part of the writer practically
all of that which relates to conditions in 1897 has been so substantiated,
and he is thoroughly convinced of the accuracy of /the statements
which follow.

25

1 / " W JW

1 %

26

It must further be j)remised, iu order that a distinct understanding
of the statements may be had, that from the standpoint of a person
unfamiliar with the conditions no portion of the infested territory con-
tains at preseut many Gipsy Moths. The residential portions of the
closely connected villages, where many colonies have existed in pre-
vious years and which at times in former years have been overrun
with caterpillars, now contain almost none. Practically the whole of
this residential portion (except Maiden and Medford), including even
the farming portion with its orchards, has been burlaped this season
wherever the insect has been found within the last three years, and, in
general, it is safe to say that only a few caterpillars have been found
in any one locality. The workers have found it easy to distinguish
between spots where an undiscovered egg cluster has been the pre-
vious winter and those where a straggling caterpillar or two have been
brought in from more thickly infested woodland districts, as well as
those where there have been only a few scattered eggs — no single
sound egg cluster.

Where one or two egg clusters have hatched the present year, the
colony is called a bad one in this residential district, so near to exter-
mination has the work progressed ! Practically, then, the insect can be
found in numbers only in the woodlands. But from the fact that vehi-
cles are constantly being driven through the territory every summer
numerous caterpillars are conveyed from the woodlands into the vil-
lages, but are then almost invariably caught under the burlap bands.
This scattering of caterpillars by carriages and carts has shown the
committee, now that extermination is approaching and now that they
have a good grasp on the entire territory, that the working policy
must be altered to some extent* Instead of devoting a great majority
of the funds to the outskirts it is necessary to at once reduce all colo-
nies where the insects are present in number to what may be termed an
"innocuous condition," since, so long as a single colony exists in which
the insects are numerous, there will always be these stragglers, which
may at any time start a new colony. How much depends upon this
work may be illustrated by the fact that in the fall of 1897 a man was
discovered carting leaves from one of the worst infested regions in the
Medford woods into Somerville. A reinfestation of Somerville would
probably have resulted. Experience has also shown that every sum-
mer at commencement time a few caterpillars are brought by visitors
to the campus of Tufts College.

After this explanation the statements concerning the present condi-
tion of the infested towns will be perfectly understood.

ARLINGTOX.

In the 1891 inspection this town was found to be badly infested, both
in the woodlands and the open and cultivated lands. At present the
territory east of Spy Pond is practically clear. Only two caterpillars

27

were found there last year. In the woodland districts only two colonies
of any extent exist at the present time. In tin- western parr of the town
an occasional e<™- cluster has been found this year. Nothing has been
done in the town for two years except burlaping, and this year in
taking off the burlaps all e,u'<r clusters found were destroyed. Tn Bpite
of this paucity of work the town is in better condition than it was two
years ago, and with means the extermination of the insect from the
whole town is only a question of a short time.

BELMONT.

This was one of the towns early found infested (1*90). and the later in-
spection showed the insect along the roads, on the farms, and also in the
woods. Many of the colonies were exterminated prior to 1896, and dur-
ing the preseut year much good work has been done there. Only an
occasional caterpillar can now he found. The residential portion of the
town was burlaped and the insects which now occur there are in the
shrubbery about residences where the people have objected to the
work.

BEVERLY.

In this town the insect was practically exterminated in 1896. In
1897 old localities have been inspected once or twice, but nothing has
been found. The original colonies, of which there were about ten. have
been wiped out of existence.

BOSTON".

Prior to 1896 the insect was practically exterminated in East and
South Boston. One colony in South Boston was cleared in 1896 and in
1897 several dozen caterpillars were taken under burlap. These had
evidently been brought in on vehicles. The Dorchester district was
badly infested several years ago. but iu 1897 only an occasional cater-
pillar was found, aud no egg clusters were found on careful inspection
in the tall. In the Roxbury district, which was considerably infested
in 1894, nothing was found on careful inspection this year. Franklin
Park, which has been referred to in a previous section, and which con-
tained in 1893 an old colony which, owing to conditions, was very
difficult to exterminate, has been absolutely free of caterpillars both m
189G and 1897. In Brighton and Charlestown the insect appears to be
exterminated. All the old colonies were burlaped and inspected in
Brighton and but one caterpillar was found. This had evidently been
brought in accidentally from some other portion of the territory.

BRMOKI.IM.

Two important colonies of the moth were found in Brookline in L8

This town is outside of the infested territory as mapped in L891. These
colonies were of several years' growth, and the most energetic work
was done in 1896 and 1897. A thorough inspection of the town was
made in the winter of 1896-97 and no other colonies were found. The

28

adjoining portions of the town of Newton were also inspected for a
distance of 2 miles, and nothing was found. The work in both colonies
has been thorough. In the immediate vicinity all trees have been care-
fully burlaped. About 20 egg clusters, however, were found at the
extremity of the colony on the Schlesinger estate, which shows that
further work will have to be done next year. The other colony, that
upon the Crafts' estate, was so thoroughly worked over during the win-
ter of 1896-97 that apparently but two egg clusters escaped. One of
these was under a building and the other uuder a stone covered with
snow. The caterpillars hatching from these two egg clusters were
probably all trapped by burlap.

BURLIXGTOX.

A woodland colony discovered in 1895 furnished the ouly caterpillars
which occurred in any numbers in 1890. This colony was thoroughly
worked over in the winter of 1896-97, and during the present season a
few caterpillars were caught by the bands, but no egg clusters were
laid, so far as could be found. Traffic through the northern part of
the town necessitates a tree-to-tree inspection, which will be given it
next summer.

CAMBRIDGE.

The town of Cambridge has been comparatively neglected until the
present season. Nearly every tree in the town was burlaped in 1897
and a few caterpillars were found. In many old localities of importance
none at all were found. Only here and there were enough caterpillars
found to indicate the occurrence of a complete egg cluster. In North
Cambridge, which has been the worst section, only three caterpillars
were found, evidently stragglers from some other locality. The portion
of the town west of Harvard Square and Massachusetts avenue is now
the worst infested region. There were three or four places where quite
a number of caterpillars were found, but the probabilities are that all
were captured. In Mount Auburn Cemetery, formerly a very badly
infested district, very few caterpillars remain.

A few egg clusters were found in Chelsea in 1896, whereas the insect
was generally scattered about the city in 1891. Most of the colonies
were exterminated prior to 1896. Burlaping in the most suspected
localities was resorted to in 1897 and a very few larva? were found,
although more may be brought in owing to the constant traffic with
Everett and Maiden.

DANVERS.

The two colonies previously known in Danvers were reported as
having been exterminated in 1896. The town, however, has not been
carefully inspected for two years and stragglers may have been brought
in. It needs a new inspection.

29

EYKKKTT.

This town was badly infested in 1891, but was in fair condition in
1894. Comparatively little work was done in 1895, owing to pressure
elsewhere, and the insect increased. Daring 1890 the town was bur-
Japed and inspected. More caterpillars were taken there in 1890 than
in any other city or town. It 1897 it was rather generally burlaped,
and several thousand caterpillars were taken. A few egg clusters
were found at the end of the season, which indicates a necessity for
careful burlaping again in 1898.

LEXINGTON.

In 1890 it was reported that the greater portion of Lexington was
cleared. In two colonies in the woodland in the northern portion of
the town much work was done during the winter of 1896-97. During
the summer of 1897 nothing was taken under burlaps in one of these
colonies, showing the insect to have been exterminated. In the other
a few caterpillars were found, but no egg clusters, indicating that
extermination was probable also in this colony. In East Lexington
village a few caterpillars were found in 1890. In 1897 there was no
evidence of any hatching, and only an occasional caterpillar was taken,
which had evidently been brought in on some vehicle. The eastern
corner of the town extends into one of the badly infested spots in the
woodland, and many trees were found infested in some of the woodland
colonies in 1896. Much work was done there in the winter and spring.
There was a woodland fire in the spring at one point, and only a few
caterpillars were found under burlap in the summer. A number of
egg clusters were found this fall. Work in these woods was not car-
ried on very extensively, for the reason that the owner intends to cut
ofi' the timber. All of the old orchard and village colonies in this
town are extinct.

A new colony was found in Lincoln during 1897. This is well out-
side of the territory mapped in L891. It was reported to the State
board by persons who noticed the stripped trees and who sent in cater
pillars in July. Some trees were entirely covered. The colony was
certainly several years old. .V force of men was set at* Work imme-
diately. About 1 acres of ground was cut over and about 0 acres
burned over, and in the center of the colony the number of insects was
reduced about 90 per cent. Apparently the insect is distributed more
or less sparsely over about 100 acres of difficult ground to work over,
since it contains many stone walls and loose ledges of rock. Next
spring all of the small brush will be burned when the larvae are small
and the stone walls will be burned over in .May. which will kill at least
two-thirds of the larvae. New sprouts will then conn4 out, thus con-
centrating the remaining Larvae, and a new burning in July will kill
most of these larva1.

30

"LYNXFIELD.

In all the colonies in Lynnfield known before 1894 the moths were
exterminated in that year or previously. Further inspection in 1895
showed several colonies in the woodland. Some of these were exten-
sions of Saugus colonies and others had existed in the woodland for
several years. By the close of 1896 these woodland colonies had been
nearly exterminated, the brush having been cut down and burned and
the trees burlaped for two years. No insects were found in some of
them in 1896, while in others a few were found. In the spring of 1897
a thorough search for egg clusters was made and a few eggs were
found. All the colonies were burlaped and a very few larvae were
found, indicating the presence of scattered eggs, but of no complete
egg clusters. The territory in November, 1897, was being inspected
for egg clusters. None had been found up to the date of writing. A
search of part of the woodland in the town was made in 1896, which
showed only one small new colony. Owing to the extent of the wood-
land in this town and its popularity as a place for outings and picnics,
the attention of the workers has been concentrated upon it.

At one time over twelve hundred estates in Lynn were infested,
mostly in and about the center of population. In 1896, during the fall
inspection, egg clusters were found in only one estate out of the 1,200.
This was in a bad colony found in 1895. In the fall of 1895, 2,000 egg
clusters were found in this colony. As a result of the remedial treat-
ment, however, in the fall of 1896, only one egg cluster could be found.
In 1897, as a result of burlaping, only one larva was found and that
was on the outskirts of the country and had evidently been brought in
on some vehicle. The extensive and beautiful "Lynn Woods Park" is
in this town, and the Gipsy Moth obtained a foothold in these woods
several years ago. During June, 1896, a colony was found in these
woods, where the caterpillars had become so numerous as to strip the
leaves from the trees and all vegetation over a small area. In the
spring of 1897 inspection was carried on in these woods down to the
time of the hatching of the caterpillars, and all known infested places
were treated and the trees burlaped. In 1896, 107,520 caterpillars,
41,535 pupa?, and 11,027 egg clusters were taken in the park colony
referred to, and in 1897 the number was reduced to 29,088 larva? and
926 pupae. The territory has not been as yet inspected for eggs, but
it will be gone over if possible in the spring of 1898. There is not the
slightest danger now of serious injury to the park, and the entire
woods can be freed from the moth in a comparatively short time.

This town, although badly infested in the early nineties, has not been
injured of late, except in a few cases. During 1896 there was an out-

31

break in the southern part of the city where the trees on about half an
acre were more or less defoliated. About half of the trees were cut
down and the undergrowth cleared out. Nearly the whole town baa
been gone over and the eggs destroyed this fall. The proximity of the
town to the Middlesex Fells renders the occurrence of straggling cater-
pillars more or less frequent, and the condition of the town at the close
of the season of 1897 was certainly no better than at the close of 1896.

MARKLKIIKAJ).

In the fall of 1896 one small colony was found in the southeastern
portion of the town, near Swampscott, and two egg clusters were found
near the center of the town, although in previous years about a dozen
colonies have been known in different portions of the town. In the
southeastern colony all of the egg masses which could be found were
destroyed and the trees cleaned up. It was in tillage land, partly in
orchard, with willows growing along a stone wall. The trees were
banded with insect lime in the spring of 1807, and after the larva- were
hatched the wall and low vegetation were burned over. Burlap bands
were placed on the trees, and outside of the burned portion 126 cater-
pillers were found during the summer. Xone were found on the burned
portion. Outside of the burlap limits two egg clusters were found.
In the center of the town, where the two egg clusters were found in
the fall of 189G, not a single caterpillar was taken.

MEDFORD.

This is the town in which the insect was originally found, and lias
contained as many as a hundred colonies in previous years. At the
present time, outside of the Medford Woods, there are not more than
three or four spots where the}' are present in any numbers. The central
and southern part of the Medford Woods maybe said to be rather badly
infested and the colonies almost continuous. In the eastern and west
era sections there are by no means as many. In the northern portion,
near Stoneham, there are only very small and scattered colonies. The
whole woods will be thoroughly inspected if the means will allow. In
November, 1897. the worst colonies were in process of treatment. The
woods were being thinned out and the egg clusters destroyed with ere
osote. The whole place has been reported in good condition for exter
minative work next season. A number of the worst colonies have
already been cleared.

Mil R0S1 •

In 1890 it was reported that a large amount of work remained to be
done in the southern portion of the town, especially in the woodlands.
This town was well inspected last winter, and in the whole northern
portion only one colony was found in which the insects occurred in any
number. Some i)[' the oldest and worst colonies seem to be wiped out.

32

The Cedar Park colony (a very bad one) is evidently exterminated.
There still remains, however, a wooded section which should have a
tree to tree inspection.

NAHANT.

Four colonies have been known at Nahant, but all have been extermi-
nated. There is so much travel to this delightful summer resort, how-
ever, that stragglers are likely to be brought in at any time.

A single male pupa was found in the town of Newton in September,
1897. The nearest infested area is in Watertown, a mile and a half away.
Some banding will be done about the spot where this pupa was found
next season, but it is not likely that any caterpillars will be caught. A
single tree in the Crafts' colony in Brookline is situated over the New-
ton border. The condition of this colony was described under Brookline.

Down to 1896 all of the colonies in this town except three had been
exterminated. One of these was reported in the fall of 1896 to be a
large woodland colony which it would take some time to exterminate.
These three colonies are known as the Newhall, the Marsh, and the
Spring Pond colonies. The Newhall colony is near the Lynnfield line.
It was burlaped in 1897 and two caterpillars found. No egg clusters
were found after close examination in the fall. This colony, therefore,
is probably exterminated. The Marsh colony is on Summit street, in
the West Peabody woods. In the spring of 1897 two egg clusters were
found. Ten thousand trees were burlaped, and in the entire summer
only one caterpillar was found, which, therefore, was evidently a strag-
gler. No eggs could be found in the fall, when the colony was carefully
inspected. It is safe to say that this colony was also exterminated,
and that it is not worth while to burlap another season. The Spring
Pond colony is the woodland one referred to in the opening sentence.
Here 130,000 larvae were taken in 1896. In January the territory was
gone over for eggs, and but two egg clusters were found. In 1897 the
whole territory was carefully burlaped, and 400 larvae taken in two
spots. Inspection in the fall of 1897 showed no eggs. In the sum-
mer of 1897 a yard in the center of the village was found to be infested.
The colony was probably 2 years old, and the insect was accidentally
introduced by the owner. Thorough work in this colony has reduced
it to insignificant proportions.

READING.

This town has been considered free for the past two years. Inspection,
however, this season shows that stragglers have been introduced and
that there must have been scattered eggs the past winter, a, thing which
is not likely to occur again.

33

Only one egg cluster was found in the residential portion of this
town in 1896, whereas they occurred in all parts of the town in 1891.
On account of the constant traffic through the town an occasional
caterpillar has been found during the past season. In the woods near
the Saugus and Maiden lines a number of caterpillars were caught
under burlaps the present season.

SALEM.

Nearly all of the colonies that were found near the center of popula-
tion in this town, and there were many, were exterminated by 1896.
The very bad colony at Harmony Grove Cemetery is certainly exter-
minated. The region known as the Salem Great Pastures, containing
thick brush, was generally infested, and all the work that was feasible
with the means provided was done up to 1806. It was then reported
that in many cases the work had been a success and in others the lack
of money resulted in cessation of work and consequent failure to
exterminate. This year all known colonies in the pastures were gone
over, beginning in April. The brush was cut and burned and wherever
larva1 or eggs were found the region was burned over with oil. The trees
were trimmed and burlaped and the whole region is now in excellent
condition. It is possible that an occasional egg cluster will be left, but
no inspection can be made this fall.

SAUGUS.

This is one of the worst towns. Colonies were found in the wood-
lands in 1803 and 1804, some of them quite large. The insects were
held partially in check, but in 1806 they were reported to have increased
and extended their limits, threatening not only to extend still farther
into Saugus woods, but to reinfest Lynn, Salem, Swampscott, as well
as other places where the moth was then nearly exterminated. In the
winter of 1806-07 and in the spring of 1807 egg clusters were treated
in these woods in all known colonies. Throughout these same colonics
about 150,000 of the smaller trees were cut out, as well as the under-
brush. The remaining trees were then burlaped and carefully watched
during the summer. The effect of this careful work is well indicated by
the following example: In what is known as Colony 17 during the fall
and winter of 1896-97, 76, 000 egg clusters were taken. In the same col-
ony under burlaps during the summer 130,000 caterpillars were taken,
and in tin' fall of 1807 rigid inspection showed six egg clusters only.
This was a very difficult block of woods to work in. containing high pine
trees, in which the moths as a general thing laid their eggs at a con-
siderable elevation above ground. In the other colonies the work has
resulted in about the same way. All of these spots will be burlaped
next year. The egg inspection during the fall o\' 1807 occupied only
about one-fourth of the time given to it the previous winter. The vil-
8057— No. 11 3

34

lages of Saugus were not burlaped during 1897, and there are prob-
ably a few egg clusters here and there. They will be inspected this
fall or winter. It is likely that other colonies will be found in the
Saugus woods, but this season's experience has shown how thoroughly
they can be worked another year.

SOMEP.VILLE.

The insect in 1891 was scattered in colonies throughout the greater
portion of this town. A steady improvement in the condition of the
city was noted down to 1890, in which year all of the known colonies
were carefully attended to. The present season almost nothing has
been found in this town, but straggling caterpillars are constantly
being brought from the Medford line. Two small colonies resulting
from this fact have been fouud this fall. They are only in spots where
an occasional egg cluster has not been found on account of the inacces-
sibility of its situation.

STOXUHAM.

The whole town was partially burlaped in the summer of 1897 and
scattered caterpillars were found which had probably been brought in
from the Middlesex Fells. The fells colonies in this town have been
watched and burlaped and have greatly improved, especially in the
southwestern corner. Very few caterpillars were taken except at the
Medford line, where they had been brought over from the Medford
woods. In the northern portion of the town only an occasional cater-
pillar has been found.

SWAMPSCOTT.

The insect swarmed in certain parts of this town in 1891. The
largest colony and one of the worst in the whole infested region was
early cleared, and no trace of the insect can now be found there. This
colony covered about 100 acres, a large part of which was woodland.
At the close of 189G it was reported that there was a small colony in
the woodland of Swampscott and three localities in which the egg
clusters were found. The three colonies where eggs were found during
1897 were burlaped, but only enough larvae taken to indicate scat-
tered eggs; not even the occurrence of a single whole egg cluster. No
egg clusters were found in the fall of 1897, although close inspection
has been made. The small woodland colony was cut over in the spring
and then burlaped, but so few larvae were found that it did not
require burning. Xone were found in the center of the colony, but on
the outside a very few, indicating that perhaps two or three egg clusters
in rocks had escaped attention.

WAKEFIE»LD.

Although the insect was numerous in this j:own in 1891-92, its condi-
tion was improved bjT work to such an extent that at the close of 1896
only five colonies were found, and few insects were found during that

35

season. The present season it is safe to say that all the upper region
of the town is tree from the insect. A few scattered larvae seem to have
been brought in from the Saugus woods, but all of the old colonies are
practically extiuct.

W ALT 1 1 A.M.

All of the old colonies in this town were practically exterminated
previous to 1895. In 189G one colony was found in the woods, which
was carefully watched, burlaped, and treated in such a way as to
promise extermination. Examination of this colony in 1897 shows that
this work was effective. A single white-oak tree at the border of the
colony, however, probably harbored a single egg cluster, as a few cater-
pillars were captured. Probably no more work will be required in this
town, although the locality just mentioned will be carefully watched
another season, and eventually another tree to tree inspection will be
made. As Waltham is one of the border towns, this result is most
encouraging.

WATERTOWN.

Although this town contained numerous colonies, all but two had
been exterminated by the close of 1890. The 1897 inspection showed
that in one of these the insect had been exterminated. The other is an
extension of Mount Auburn Cemetery, in Cambridge, which has already
been mentioned under the head of Cambridge. Very few caterpillars
were found there this summer.

WINCHESTER.

The Winchester woodland contained a part of one of the badly
infested wooded localities reported upon in 1895. Careful work was
done in 1896 in the western Winchester woods. It was followed up by
careful winter work. Considerable tracts were cut over and burned
over, then inspected and -burned again. The numbers of the insect
were very greatly reduced and very few individuals can now be found
there. In one of the worst colonies 33 acres of woodland was cut
over by the owners and the brush burned off by the committee and
the ground and sprouts burned over. No evidence of the insect has
since been found in this tract of land, except at two points on the out-
skirts, where the wood was not cut and where a few caterpillars have
been trapped this summer. In another colony the committee cut off
the wood from about 19 acres and this wood was marketed by the
owner of the land. In the southeastern borders i){' the town is a tract
of tanning land where there have been strips oi' badly infested wood-
land. Much of this was cut and cleared up in the spring of L897 and
vast numbers of eggs destroyed by tire. This work and this summer's
burlaping has so greatly reduced the insect as not only to prevent its
spread, but to promise practical extermination almost in a single sea-
Son. In the residential portion of the town the condition is excellent
and only occasional caterpillars are found.

36

WINTHROP.

This town, although generally infested at one time, was carefully
inspected in the fall of 1896 with the result that only three small egg
clusters were found. A few caterpillars were trapped in the summer
of 1897, but no egg clusters were found in the fall, so that the town is free
from the insect except for stragglers which may appear in another year,
and it must be remembered that the possibility of bringing in strag-
glers another year will be very greatly less than last season, owing to
the radical work which has been done in the woodland colonies.

WO BURN.

The village and southern portions of the town of Woburn have been
rather badly infested, but in 1896 it was reported that no moths were
known to exist in the town at that time, except in the southwestern
portion, near the Winchester-Lpxington boundary. In 1897 there were
only two places in which any number of caterpillars were found. Both
were in old stone walls covered Avith vines. These localities were thor-
oughly burned out. In the southwestern woods a considerable num-
ber of caterpillars were captured near the place where old colonies had
been destroyed the previous winter, but extermination in these dan-
gerous places has nearly been reached. Were there no reinfestations
from the neighboring borders of Winchester and Lexington, there
would be no difficulty iu absolutely clearing the town of Woburn in a
very short time with sufficient means.

THE TERRITORY AS A WHOLE.

The infested territory as a whole now includes portions of 33 towns,
portions of 31 towns having been included in the line drawn after the
inspection of 1891. There have been at one time or another since 1891
within this territory, which, by the way, comprises approximately 220
square miles, 1,893 so-called colonies of the insect, a colony meaning a
circumscribed spot infested by caterpillars. A colony may be very
small and contain comparatively few insects, or it may cover a space of
a number of acres and contain caterpillars by the thousand. At the
present time it is safe to say that more than nine-tenths of these 1,893
colonies have been practically exterminated. The 1891 boundary line
of the infested territory could at the present time be drawn in to a
very considerable extent, although, at present, there exist the remains
of three colonies outside of that boundary line, viz, two in Brookline
and one in Lincoln. Throughout the residential and cultivated portions
of the territory, as a whole, the Gipsy Moth is a scarce insect. The
dangerous colonies which still exist are in the woodlands, and at pres-
ent every one of these is in such condition that the insect is well in
check. The consequence of the prompt availability of the funds
appropriated by the legislature of 1890-97 has been that the entire
field is well in view and that the prospects are more encouraging than
ever before.

37

CONCLUSIONS,

It results from this reasonably thorough investigation that the
writer is in position to say, as preliminary to his conclusions concern-
ing future work, that the State of Massachusetts is most heartily to be
congratulated upon the manner in which tin's work has been carried
on. The effort of the State will rank as one of the great experiments
in economic entomology in the history of the world. On the whole, it
can be safely said that there has been no waste of the State funds.
The officials in charge had to feel their way at first, but. contrary to the
history of novel enterprises of this kind, there have been no disastrous
experiments. The work has been admirably directed toward the main
end almost from its inception. No criticism can be made, even in the
light of present experience, of any of the work carried on since it has
been in the hauds of the State board of agriculture. The methods
used have been not only sensible but ingenious to a high degree. No
promising line of experiment has been neglected, and many have been
followed out which would not have suggested themselves to le>s able
and original minds than those having charge of the work, lfesults
have incidentally developed which have already had a much wider and
more important bearing than the destruction of this one insect, and it
is safe to say that, even at this time, the total outcome of the work has
been of great value, not only to the country at large but to all civilized
portions of the globe.

The organization of the corps of workers, the selection of the men.
ihc systems, not only ot supervision, but of general organization, down
to the simplest details and the economical expenditure of the funds, all
seem as nearly perfect as can be desired. The writer has talked at
length with all of the principal men connected with the work, has
studied unnoticed the operations of the gangs of men in the held, has
earnestly endeavored in every possible way to substantiate critical
comments which have come to his ears, and is honestly convinced of the
truth of all of his statements, which he nevertheless realizes may seem
at first reading to be overenthusiastic. The most interesting feature ot'
the investigation and one which is rarely seen in such State work i> the
vivid interest taken by practically all of the employees in the thorough-
ness and success of the work. The principal men are full of enthusiasm,
full of the importance of their labors to the interests oi t aud

at the same rime full of a genuine and vivid scientific interest in the
experiment which they are helping to carry on. So great has
been the interest and so arduously have they labored that in several
- they have broken down in health. The field director of the work
was seriously ill through many weeks iA' the present season, one ot the
superintendents of sections has lost lii>> health entirely from overwork,
and another I have seen dragging himself about in the field superin-
tending his men when he ought to have been in bed.

It follows then that the work which has been done has been wisely

38

done and has been economically done. When we say that it has
been wisely done, we mean that, admitting that the State fight is
or was to be for the extermination of the species, the steps taken
have been wise ones, and after a review of the entire work, and
after the consideration of what is known as the habits of the insect,
as well as of local conditions in 1889, it can not bnt be admitted
that the effort of the State to exterminate the insect has also been
wise. It is true that a large amount of money has been expended,
and it is also true that much more money must be expended before
extermination can be accomplished; but it is undoubtedly safe to say
that the money which has been and will be spent by the State in this
work is but as a drop in the bucket to the loss which would have been
occasioned by the insect had it been allowed to spread unchecked.
This loss would have fallen not 011I3- upon the State of .Massachusetts,
but upon other States of the Union, so that we may say that the State
work has not only been wisely done, but that it has been patriotically
done. At the present time there can be little doubt that the extermi-
nation of the insect is possible and that it will be only a question of a
few years, if adequate State appropriations are continued. The simple
fact that it has unquestionably been exterminated over considerable
stretches of territory and that extensive colonies existing in the most
disadvantageous territory for the prosecution of remedial work have
been so thoroughly destroyed that not an individual has been found
for three years with the most rigid annual inspection is sufficient proof
of this possibility, for what can be done for one section like this can be
done for all, if the means be sufficient.

Thus the questions as to whether the State has done the right thing
in appropriating for the extermination of the insect instead of for hold-
ing it in subjection, and as to whether the money has been used in the
best possible way to forward this end, may both be answered emphati-
cally in the affirmative. The condition of the infested territory at the
time of writing (November, 1897) is by far better than it has ever been
before. This fact is largely owing to the promptly available appro-
priations of January and February, 1897. A great amount of admi-
rably effective work was done at the critical time of the year, and
the results are obvious. The writer believes that the condition of
the entire infested territory at the present day is such that with the
prompt appropriation of the amount asked for by the committee at the
beginning of the coming session of the legislature the work which will
be carried on during 1898 will be of so effective a character that even
those who most gravely doubt the policy of the State efforts will be
convinced of the efficacy of the work. A continuation of the appro-
priations for a few more years is unquestionably a necessity. Were
the appropriation to lapse a single year, the work which has been done
during the past six years would largely be lost. The $775,000 already
appropriated would have been spent in vain.

39

There is one rather serious point which still remains to be con-
sidered. It has been shown that three large colonics of the insect
have been discovered during- the past two years outside of the bound
aries of the survey of 1891. If such colonies — all of them of at least

lour years' standing and one of them of at least eight years' standing —
have only just been found, may there not be others the existence of
which is still unsuspected by the committee? It is probable that this
is the case, and it seems to the writer that not only should a warning
circular be seut to almost every property holder in a border of at least
two towns deep around the line of 1891 with a request to inform the
committee of the existence of caterpillars which resemble that of the
Gipsy Moth, but that a thorough inspection of these same towns with
as large a force as can be devoted to the purpose should be made in
the near future. The knowledge of the Gipsy Moth work is now so
widespread in Massachusetts and people have become so much inter-
ested in the work that it is not likely that many such colonies will be
found, yet knowledge as to the existence of every one is an immediate
necessity.

O