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CIRCULAR No. 58,

United States Department of Agriculture,

BUREAU, OF ENTOMOLOGY,

L. O. HOWARD, Entomologist.

REPORT ON THE GYPSY MOTH AND THE BROWN-TAIL MOTH,
JULY, 1904.

3 By C. L. MARLATT,
In charge of Experimental Field Work.

The renewal, in the summer of 1904, of excessive damage by the
gypsy moth in the woodlands about Boston, and more or less in the
residential districts, was brought to the attention of the Secretary of
Agriculture primarily by Congressman Ernest W. Roberts, of Chel-
sea (Boston), and about the same time, also, by the secretary of the
Massachusetts State board of agriculture, Mr. J. Lewis Ellsworth,
in a letter addressed to the Entomologist of the Department. In com-
pliance with the request of Mr. Roberts, the Secretary of Agricul-
ture authorized a thorough investigation of the present status of the
gvpsy moth in Massachusetts, and, at the same time, of the brown-
tail moth. Acting under instructions from the Entomologist, Dr.
L. O. Howard, the writer spent some three weeks (July 1-22) in

going over the infested districts about Boston, and visiting certain

localities in adjoining States. The conditions found, relative to the
two pests named, are summarized below.

THE GYPSY MOTH.
(Porthetria dispar Linn.)

The work of the gypsy moth committee terminated in January,
1900. The condition of the infested district about Boston at that
time, as shown by the reports of the committee, and by careful exam-
inations made by the Entomologist, Doctor Howard, and also, a little
prior to the termination of the work, by the writer, was most satis-
factory, from the standpoint of control, at least. In other words,

y

the very efficient and careful work of the agents of the committee had
exterminated the moth in many of the restricted outer colonies,
reduced it to inconsiderable numbers in others, and prevented defolia-
tion in the -more generally infested districts. The policy of the com-
mittee had been to effect extermination, as fast as possible, in the
outer portions of the infested region, working gradually inward, but
at the same time keeping up sufficient work in the central districts to
prevent any material injury.

In the prosecution of this work the committee had apparently good
reason to believe that extermination had been effected in a great many
isolated colonies, including a considerable number of large and
important ones, and it was beheved by them that with sufficient funds
actual extermination of the insect over the entire region of infestation
would ultimately be accomplished. Whether this was possible or
not, at least it had been demonstrated that the gypsy moth could be
exterminated in isolated colonies, and reduced to inconsiderable num-
bers, or to a status approaching extermination, in areas of more gen-
eral infestation.

With the cessation of the operations of the gypsy moth committee
under State appropriation, the gypsy moth was left to multiply and
spread at will, save for work undertaken here and there by individ-
uals, and, in the residential districts, by the local authorities of many
of the infested towns, the latter work being usually under the charge
either of tree wardens or of street commissioners. In the case of the
Fells reservation, also, a good deal cf work has been done, especially
during the last two years, under the general direction of Mr. B. de
las Casas, chairman of the Metropolitan Park Commission, by Mr.
Charles F. Price, in charge of the reservation. Other large areas of
forest infestation, such as those surrounding the Lynn woods, and
many private estates, have gone practically untreated. In the resi-
dential districts of some towns very good work has been done, as
noted, by individuals or the town officials; and, while the gypsy
moth has not been exterminated in these districts, it has been kept
down, so that no marked defohation of street and yard trees has
resulted.

The amount expended during the last two years in such work of
control, judging from careful inquiry and estimate, probably almost
equals the amount expended by the State during the years of its
most active operations against the gypsy moth, namely, approaching
$200,000. A single individual, Gen. S. C. Lawrence, has, for the last
three years, had a large force of men working on certain gypsy moth
colonies in his own and adjorming forest lands, expending each year,
as he assures the writer. more than the actual value of the lands.
Hundreds of individuals in each town have expended sums ranging

3

from $10 to $100 in the control of the gypsy and brown-tail moths.
Nearly every town corporation has made expenditures of from a few
hundred dollars to several thousand dollars for the same purpose. A
number of experts, or foresters, have gone into the business of clear-
ing the premises of individuals of gypsy and brown-tail moths, and
find constant employment for considerable forces of men. In general
this work is excellently done. The chief difficulty, however, is that
this and other work against the moths is scattering or patchy; in
other words, while some take good care of their property, others give
no attention to theirs, thus leaving numerous spots for the unchecked
multipheation of the pests. The result is, that while practically as
much money is now being expended as was formerly spent by the
State, the results are by no means comparable, from lack of general
direction and uniformity.

As a consequence of the general reduction in the number of gypsy
moths at the close of the work by the State, for the first two years
very little notable damage was exhibited in either the woodlands or
the residential districts. In September, 1902, the writer made a
rather careful survey of the worst gvpsy-moth regions, in company
with Mr. A. H. Wirkland, former entomologist of the gypsy moth
committee. At this time very little damage in the way of actual
stripping of considerable areas of woodland was to be seen. A few
comparatively small areas of actually-defoliated woodland were
found, and the general presence of the moth was noted in the central
residential districts always worst infested, but even here there was
very little actual stripping. There was ample evidence, however, that
the moth was on the increase, and promise of considerable damage in
the immediate future. The comparatively httle injury in the wood-
lands in 1902 was a matter of surprise, and the suggestion was made
by Mr. Kirkland that this had probably resulted from the attack of
birds and other natural enemies. The greater scarcity of such nat-
ural means of control in the residential districts was suggested as the
explanation for the greater infestation here noted.

The conditions found in 1902 scarcely prepared the writer for the
status shown in the course of the investigations just completed. Dur-
ing the years 1908-4 the gypsy moth had evidently made extraordi-
nary progress, and a condition of infestation and defoliation or strip-
ping was found which the writer had never before seen in the gypsy-
moth region, and which was undoubtedly many times greater than in
the worst of the earher years of gvpsy-moth damage.

In company with Mr. A. H. Kirkland, as assistant and guide, the
writer made a thorough investigation of substantially all of the
regions about Boston known to have been infestéd by the gypsy moth
in 1900, and of certain new colonies which have been discovered since
that time. On one occasion we were accompanied by the gypsy moth

4

committee of the Massachusetts State board of agriculture, General
Lawrence, Professor Fernald, and others, in'a tour of inspection
throughout the worst districts in Medford, Malden, Melrose, and the
Middlesex Fells reservation. Another day we were accompanied by
Congressman Roberts and local officials from several of the worst
infested towns, and also by Mr. Las Casas and Superintendent Price
of the Fells reservation. In various towns we received assistance and
guidance from the local tree wardens and street commissioners, and
notably, in Newton, from Mr. C. W. Ross, street commissioner. On
four days Mr. Kirkland and the writer were accompanied by Mr. H.
L. Frost, a forester who has been doing excellent work in the control
of the gypsy and brown-tail moths in Arlington and other towns. A
map (fig. 1) of the infested areas was prepared and accompanies
this report.

The present area infested by the gypsy moth, as shown by fing care-
ful examinations made, is substantially the same as at the close of the
work by the State of Massachusetts. There has, in other words,
apparently been very little extension in the area infested. Some
important new colonies were discovered, but these were within the
general limits of the old range of the insect. The failure of the gypsy
moth to widely extend its range during the four years since 1900 is
largely due to the fact, already noted, that at the close of State opera-
tions against this insect it had been reduced to such inconsiderable
numbers that it was not until the present summer (1904), or perhaps
to a less extent in the summer of 1903, that it had gained sufficient
headway to furnish favorable conditions for distribution and the
establishment of new colonies. Its excessive multiplication in the
summer of 1904 will very probably lead to considerable extension of
its range, and many new colonies will undoubtedly be started this
vear (1905).

The area of worst infestation, where general stripping of forests
has resulted, extends in a broad avenue raoen Arlington and Winches-
ter, or more properly from the western border of the Mystic Lakes,
across Medford, including the southern edge of the Fells reservation,
a portion of Melrose, and the upper half of Malden, and continues
eastward through Saugus to the Saugus River. In this region the
forests and the street trees are, as a rule, very generally defoliated
and as bare as in winter, and altogether several thousands of acres of
completely defoliated woodland occur in this strip. Spots of strip-
ping ranging from 50 to several hundred acres, as indicated on the
map by the cross-hatched areas, were found in Winchester, Lexing-
ton, Woburn, northern Melrose, and Saugus; and there were also
eereiicnablo areas bounding the northern side of the Lynn woods,
a single large colony in the center of the Lynn woods just above

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5

Walden Pond, and areas in Revere, Belmont, Watertown, and western
Cambridge. \

Scattering infestation, that is, the occasional or fairly general
occurrence of the larve of the gypsy moth, without, however, result-
ing in complete or notable stripping of the street trees and forests,
was found through much of the southern half of the Fells reservation,
and practically throughout the towns lying within the area of worst
infestation indicated, and as far south as the Charles River. Exterior
to this area of general infestation, scattering presence of the gypsy
moth was found in Lexington, Winchester, and Woburn to the north-
west; in Stoneham, Wakefield, Saugus, and Reading to the north;
and in Peabody, Salem, Beverly, Marblehead, and Lynn to the north-
east. To the west, Arlington, Belmont, Watertown, and Cambridge
west of Harvard Square are much infested. In Newton there are
perhaps some twenty-five small points of infestation, as reported by
the street commissioner, Mr. Ross. Very good work in the way of
control has been done in this town, and with the exception of the new
colony located near Newton post-office, on the Van Etten estate, only
scattering larve were found. The colony just referred to was dis-
covered last year (1903), and represents a spot of bad infestation,
covering a considerable area of garden, orchard, and ornamental
plants. In the southern portion of Newton is located one of the
worst of the outer colonies found during the course of the work of the
gypsy moth committee. This colony, near the intersection of Dedham
and Parker streets, originally covered several hundred acres of wood-
land, and was made the subject of very thorough extermination work
by the committee. This work has since been followed up.to some
extent under the direction of Mr. Ross. A careful examination of
this area shows much of it still free from the gypsy moth, but occa-
sionally larve were found, showing that there is still a scattering
infestation here and there which in a few years will be sufficient to
repeat the damage of 1896, when the colony was first located. No
larvee were found in 1902 or 1903 in the area covered by this colony,
and the insect is evidently, therefore, just beginning to get a new
start. In South Boston the gypsy moth has increased very little, and
the extermination of several of the worst colonies seems to have been
effected. This is true of the Dorchester colony (Sargent street),
where a considerable residential area, including also some forested
hillsides which were badly infested in 1898, shows now no examples
of the insect. The infestation still exists in the residential district at
West Cottage street, Dorchester. In the old colonies examined at
Brookline no larve or other indications of infestation were found. —

One of the most interesting features of the investigation was the
demonstration that in a good many areas the careful work of the
gypsy moth committee has resulted in the extermination of the insect.

6

This is due entirely to the work of the committee in some instances,
and in others, where the work of the committee was only of one or
two years’ duration, the insect had evidently been reduced to such
inconsiderable numbers that the natural enemies had completed the
work of extermination. This is notably the case in the Georgetown
colony, which had only one year’s work. Other bad colonies in which
the gypsy moth has not reappeared are Mount Gilead colony in Lynn
woods, the colonies at Spring Pond, Peabody, Cedar Hill in Swamp-
scott, Sargent street in South Boston, the Overlook colony in Frank-
lin Park, and a considerable colony in the extreme western portion
of the district in the town of Lincoln, the Schlesinger colony in
Brookline, and a good many other less important points of infesta-
tion. Several of the areas in which the gypsy moth committee
reported the moth as exterminated, and which now show slight
infestation, may have become reinfested from other districts in the
intervening years. The exterminated colonies enumerated, and the
general control shown at the close of the work of the gypsy moth
committee, indicate with sufficient emphasis that intelligent and
efficient work against the gypsy moth will prevent any material
damage to woodlands or residential districts.

This discussion of the gypsy moth has related entirely to the
infestation about Boston. Numerous reports of infestation at remote
points, and occasionally in the adjacent States, have been received
by the gypsy moth committee, and by others interested in this insect.
All of these reports, with the exception of one, have.proven to be
misidentifications, other insects having been mistaken for the gypsy
moth. Most of these reports are based on the occurrence of the
brown-tail moth, which has a much wider range, and which is very
commonly confused with the gypsy moth in the popular mind.
While the writer was conducting these investigations about Boston
a very persistent and apparently well-authenticated report came to
his attention of the occurrence of a well-established colony of the
gypsy moth at Nashua, N. H. A visit to this town demonstrated
that this, like most of the others, was an instance of confusion of the
gypsy moth with the brown-tail moth, the insect at Nashua proving
to be the latter species. In Massachusetts the most remote authentic
point of infestation was in East Bridgewater. The writer visited
this point and found that the insect had been actually introduced
here, possibly maliciously, or possibly accidentally, but had been
thoroughly exterminated. The infestation was limited to an isolated
apple tree growing in the angle of a dwelling house, and was dis-
covered in 1902. It proved to be a comparatively easy matter to
thoroughly eradicate the pest here, and there was no evidence of
work this year.

7

The point of infestation referred to outside of the region about
Boston is in the city of Providence, R. I. This infestation has been
made the subject of a special report by the Rhode Island State board
of agriculture, namely, Bulletin No. 13, published September, 1901,
by the late James M. Southwick, curator of the Roger Williams Park
Museum. The discovery of the presence of this insect in Providence
was made in July, 1901, and was investigated thoroughly at the time
by Mr. Southwick, with the assistance of Prof. A. H. Kirkland, who
was called down from Boston. When discovered the gypsy moth was
confined to the west side of Providence, where it was established in a
half dozen or more distinct colonies. The occurrence of these distinct
centers of infestation, all of apparently the same age, in the heart of
the city, leads to the suspicion that the insect may have been malici-
ously colonized at these separate points. It is impossible to believe
that these distinct colonies should have been accidentally started in
Providence at the same time, especially in view of the difficulties in
the way of the transportation of the gypsy moth and its very slow
spread about Boston, as indicated by its history during the last thirty-
six years. The infestation in Providence illustrates one of the great
dangers from the gypsy moth. It is readily spread by carrying egg
masses, and maliciously-inclined individuals can thus easily start new
colonies at any distance from the present infested area. In view of
this, as emphasized by the Providence infestation, it is highly desir-
able that heavy penalties be provided for any malicious colonization
of the gypsy moth. The important points of infestation in Provi-
dence are indicated on the accompanying map (fig. 2). The writer
was assisted in locating their exact position by Messrs. Joseph D.
Fitts, supervisor of parks, Providence, and C. A. Davis, present
curator of the Roger Wilhams Park Museum. At the present time
these colonies are still in existence, in spite of local work done in the
way of control. Notable stripping has not occurred this year, but the
larvee and pupze were easily discovered at the points of infestation,
and there is, therefore, opportunity for much increase in the future
and a repetition of the experience about Boston.

"MEANS OF CONTROL.

The work of the gvpsy moth committee of the State of Massachu-
setts developed a mumber of means of controlling the moth of the
highest practical value and efficiency, and nothing can now be sug-
gested in the way of improvement on these methods. The general
adoption and enforcement of these will undoubtedly keep the gypsy
moth in substantial control, so that no material damage to woodlands
or to shade trees in residential districts need be feared. In the case

of small properties, or where but a few trees are to be protected, these

8

means of control can be employed effectively and at reasonable cost by
the individual owner. This is true, also, of the shade trees in resi-
dential districts, coming under the supervision of the street com-
missioners or other local officers. Where, however, large areas of
woodlands are badly infested, the cost of control is beyond any. reason-
able expenditure by individual owners. As already indicated, such
control, for a year or two at least, may much exceed in cost the actual
value of the land, rendering it prohibitive so far as the individual is
concerned. Furthermore, in the case of individual holdings, without
any means of enforcement or corrective work, many will take little
interest in the gypsy moth, and therefore do nothing to prevent its
local increase, thus nullifying the work of others. In the case of
large public domains, also, as, for example, the Middlesex Fells
reservation, the cost of control is beyond any reasonable portion of the
appropriation for the maintenance of such reservations which might
be set aside for work against the gypsy moth.

If the gypsy moth is to be effectively controlled, it will be necessary
to have concerted action over the entire infested area, and this will
necessitate a central authority and.direction. There is a wide diver-
sity of opinion as to the best method of carrying on such work. The
plan employed by the gypsy moth committee consisted in expending
a lump appropriation by the State in control or extermination of
colonies throughout the infested district, the State appropriation
covering all of the expense, none of which, therefore, was charged to
the town or individual benefited. This system has some advantages.
It has, however, the objection that it does not give any incentive for
local control, or the protection of property by the individual. It
therefore seems to the writer preferable to devise some system in which
the cost of control would be divided between the individual owner,
the town, and the State or National Government, should national aid
be granted. This idea is not altogether original, but has been given
somewhat in this form by various persons who have given thought
to the subject. It has been suggested that the individual whose prem-
ises were found to be infested should be charged with a portion of
the cost of the extermination not to exceed the taxes on the infested
property, the cost of control above this amount to be divided in accord-
ance with some determined ratio between the town and State. The
advantage of this system is simply that it keeps up, in the individual
and town, a wholesome interest in the control of the pest, and in many
cases the individual will take some trouble to keep his premises clean,
and the town, likewise, will institute care of the streets and parks,
while under the old system little or no individual or local effort will
be made to prevent infestation or to stamp out the gypsy moth. The
damage now being done, by the gypsy moth is so widespread ‘and so
severe that some general system of control must be provided for at

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once if the beauty of the forest and residential districts about Boston
is to be maintained. The cost of control will undoubtedly be less,
under efficient general direction by some central authority, than the
patchy and more or less intermittent work now being done.
~The fact should not be lost sight of that control of the gypsy moth
will be a continuous charge on the State, towns, and individuals. In
other words, this insect has now reached a stage when extermination
is practically impossible. The cost of control will vastly decrease,
however, once the present excessive infestation is overcome. A large
expenditure for two or three years must be expected, after which a
much smaller sum will be sufficient to locate any important colonies
which may develop, and effect their substantial extermination. The
cost of protection in residential districts and on private properties of
small area should, in a few years, be reduced to almost nothing, if
good work be done for two or three seasons over the whole area. The
outlook, therefore, is not necessarily a serious one. Such control, fur-
thermore, will very largely check the wider distribution of the gypsy
moth, and substantial protection will thus be afforded to the State of
Massachusetts and adjoining States. Even left to itself the moth
spreads very slowly, as shown by the rather limited area now infested
after over thirty years of the presence of the pest about Boston. The
danger from natural spread, therefore, to the State at large and to
the adjoining States is small. A slow spread must necessarily be ex-
pected, but with efficient control it will be many years before it widely
extends its range in Massachusetts. ,
Another important step which may be taken looking to the control
of this pest is the introduction of its natural enemies from Europe and
Asia. As long as the operations of the gypsy moth committee were
conducted solely to the end of extermination, it was not especially
necessary to introduce natural enemies. For the successful introduc-
tion of these it would have been necessary to have kept undisturbed
large colonies of caterpillars in which the foreign parasites and pre-
daceous enemies could multiply. With the object of extermination in
view this was distinctly undesirable, but now that extermination is
out of the question it becomes desirable and feasible to make the effort
to introduce such natural enemies and to leave undisturbed isolated
colonies of the moth in woodland districts in which these experiments
can be conducted. It is well known that in Europe and Asia, the
original home of the gypsy moth, the pest is not often very destruc-
tive. Bad colonies will occasionally appear, only to disappear again
in a year or two. This disappearance and the general inactivity of
the moth in its native home are doubtless very largely due to the
efficiency of parasitic and predaceous insect enemies. From the
studies of European entomologists and foresters, such natural enemies
are well known. The introduction of these into Massachusetts would

3

10

not be attended with any possible risk, as the insects introduced feed
solely on the larve of the gypsy moth and other allied pests, and in
the absence of such food themselves perish. If national aid is to be
granted to the State of Massachusetts in its warfare against this pest,
such aid might very properly be in the direction of securing, import-
ing, and installing such natural enemies. It should not be lost sight
of, however, that any work of this character is purely experimental,
and its value to be determined only after an interval of four or five
years or more. It would probably take at least two summers in
Europe to make effective importations of the parasites, and two or
three more years would be necessary for their large multiplication in
the gypsy-moth colonies about Boston. Furthermore, such importa-
tion might in the end prove not to be especially valuable as a means
in the control of the pest. Therefore, during such experimental work
the control of the pest by standard means should be kept up over the
entire area infested with the exception of the particular spots of
infestation, or colonies set aside for experiment with natural enemies.

THE BROWN-TAIL MOTH.
(Huproctis chrysorrhe@a Winn.)

The brown-tail moth is now even better known about Boston than
is the gvpsy moth. The widespread information relative to the
brown-tail moth arises chiefly from the fact that the hairs of the
larvee are distinctly poisonous and nettling, and thousands of people
throughout the range of this pest have been poisoned the present sum-
mer or during past vears. The hairs produce on sensitive subjects
(and very few are entirely immune) a rash or nettling, with some fes-
tering, which lasts for a week or more, and is attended with more or
less itching and irritation. This poisoning may result from the
falling of the caterpillar on the neck and hands or clothing of the
passer-by, or from the loosened hairs shed from the cast larval skin
at the time of transformation to the chrysalis stage.

The loosened hairs, or the shed skin, are blown about by the winds
and frequently attach to clothing hung up in yards for drying. By
this means they are conveyed to the skin, resulting often in very gen-
eral inflammation.

In addition to its very distinct importance as a source of discomfort
to human beings, the brown-tail moth is an important tree pest, and
is common in orchards in Europe. It was accidentally introduced
into Somerville (Boston) and was brought to the attention of the
gypsy moth committee in the spring of 1897. The investigations con-
ducted at the time by the gvpsy moth committee led to the belief that
it was introduced by a floral establishment, which had been importing
roses from Holland and France previous to 1890. It seems probable

11

that this pest was introduced on this stock, and, escaping into near-by
pear orchards, had gained considerable local spread before it was
noticed. |

A general account of this insect has been published by the gypsy
moth committee, and it has lately been made the subject of a special
volume by Prof. Charles H. Fernald, of Amherst, assisted by Mr.
A. H. Kirkland. The larve of the brown-tail moth feed by prefer-
ence on the foliage of fruit trees, especially pear and apple. The
chief damage, therefore, in this direction has been in orchards or on
fruit trees grown in yards. It has, however, a wide range of food
plants, and will subsist on many forest trees, although notable damage
or forest stripping has not been characteristic of it. The habits of the
insect render it much more readily controlled than the gypsy moth.
The winter is passed in the half-grown larval stage in small but con-
spicuous webs attached to the terminal twigs. The chief means of
control is the collection in the winter of these webs and burning them,
and, if this be done with any degree of thoroughness, trouble from
the brown-tail moth may be very largely overcome.

Unlike the gypsy moth, the female of the brown-tail moth is a
strong flyer, and hence the distribution of this insect has been very
rapid. It has now overrun southern New Hampshire and south-
western Maine, as well as the northeastern counties of Massachusetts,
and will undoubtedly extend its range widely in North America in a
comparatively few years. There is no means of preventing such ulti-
mate spread, but prompt effort at control will much retard its prog-
ress. During July, 1904, while the writer was conducting his inves-
tigations about Boston, the moths of this insect were emerging in great,
numbers, and were attracted in their nocturnal flight to electric and
other lights. It was no uncommon sight to see electric-lght poles
whitened by hundreds of these snowy white moths, and thousands
were killed about the electric hghts. Some benefit could undoubtedly
be obtained by a trap connected to electric ights which would destroy
more of the moths than the lights do themselves.

During the time when the flight of these moths was at its height
enormous numbers of them were brought by favoring winds into the
heart of Boston, causing considerable interest and excitement in
Newspaper Row, the swarm having centered there, and resulted in a
number of accounts, illustrated by photographs locally taken, in the
daily papers of the following morning.

The distribution of the brown-tail moth, as already indicated, has
been in a northerly direction. South of Boston it is known to occur
in the double tier of towns bordering Massachusetts Bay as far as
Scituate. The entire northeastern portion of Massachusetts was
invaded as early as 1899. By 1902 the invasion had extended west-
ward to Brockton, Hudson, and Stow, in Massachusetts. The moth

12

was reported at Kittery, Me., as early as 1899, by the late Prof. F. L.
Harvey. It has also been reported by Prof. James Fletcher, the
Canadian Government entomologist, as occurring at St. Johns, New
Brunswick, where it was supposed to have been transported by
steamers plvin@ between Boston and St. Johns. In 1902 the moth
was abundant in all the towns along the eastern division of the Boston
and Maine Railroad, as far as Portsmouth, N. H. During the last
two years, and especially the summer of 1904, the moth must have
extended its ravages considerably in both New Hampshire and Maine.
Its occurrence at Nashua, N. H., has been referred to in the discussion
of the gypsy moth. The counties of Rockingham, Hillsboro, and
Stafford, N. H., are known to be pretty generally infested.

Strong gales of wind at night during the flying season must extend
the distribution of this moth many miles. This was illustrated by
the results of the high gales prevailing in New England July 12-14,
1897, which were largely responsible for the spread of the moth over
much of the area now infested. The ability of this moth to extend its
range over much of northeastern United States in the near future is
abundantly shown by this instance and its history up to the present
time.

The control of this moth will need, perhaps, less of town and State
aid than the gypsy moth, but some provision should be made to
enforce the removal of the caterpillars’ webs in winter, and the
authorities charged with the work against the gypsv moth should be
empowered to enforce corrective work against the brown-tail moth
also. In the introduction of parasites for the gypsy moth the brown-
tail moth should also be considered. These two insects have many
common natural enemies, but the special enemies of each should be
introduced. For detailed information on the history of the brown-
tail moth and on means of control, reference is made to the publica-
tions cited above.

Approved:

JaMES WILSON,
Secretary of Agriculture.

| Wasuineoton, D. C., Alarch 21, 1905.

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