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THE BROWN-TAIL MOTH.

(Euproctis chrysorrhæa, L.)

As will be noted from the resolutions which were passed last spring by the General Assembly, the money appropriated was to be expended for the suppression of both the gypsy and the brown-tail moths. While these two insects have been companion pests and have thus fallen under the ban of law to an equal degree, they are very different in their life history and must be dealt with in a different way. The principal reason for this is that the gypsy moth spreads very slowly, and largely by human agencies, and therefore can be controlled or suppressed, and even exterminated in areas where sufficient work is done to that end. It is also somewhat limited in its present extent as compared to the more recently imported brown-tail moth. Both sexes of the brown-tail moth are strong flyers and spread rapidly of their own accord, and are now distributed over a large territory. Hope for extermination in this country is entirely gone. If exterminated in one section of the country, a favorable wind at the time of the flying of the moths will reinfest this territory, within one season, almost as thoroughly as if no work had been done.

The habits of the brown-tail are also different, and such that the fight against this insect is quite simple and may be left more generally to individual efforts. The egg clusters of the gypsy moth in which the insect passes the winter are hidden away in various nooks and corners as well as on trees, and it takes experienced men and close scrutiny to discover all the clusters which may be found in any given locality. The brown-tail moth, on the other hand, passes the winter in the caterpillar stage in closely woven nests which are nearly always found at the tips of the branches of the trees which it infests. These nests are, therefore, easily seen even by unskilled workmen, and can. be readily cut off and burned to destroy the insect.

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FIGURES NOS. 1, 2, 4, AND 5 DRAWN FROM NATURE BY J. H. EMERTON

No. 1.-Female brown-tail moth.

No. 2.-Winter web of brown-tail moth caterpillars.

No. 3.-Pruning shears suitable for removal of winter webs.

No. 4.-Brown-tail moth caterpillars, enlarged.

No. 5.-Brown-tail moth caterpillars, natural size.

From special report on the Brown-Tail Moth, Mass. State Board of Agr., 1903.

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Fortunately also the brown-tail moth, although causing a great deal more personal discomfort when present in large numbers, is not so serious a pest as the gypsy moth. As has been learned already, the gypsy moth feeds on nearly all kinds of vegatation, including both deciduous and evergreen trees, and is especially destructive to the latter. The brown-tail is limited in its food-plants, being found. usually on fruit trees and on but a few species of forest trees, and does no damage to field and garden crops. It is an insect also which, on account of its life history, is much more subject to the vicissitudes of climate and to destruction by fungous and parasitic insect enemies. In this connection it may be noted that, according to the reports from Massachusetts, a fungous disease, Empusa aulica (Empusa grylli), has been very destructive to the brown-tail caterpillars in many sections of the infested territory; so much so that in a great many places where the brown-tail has been a more disagreeable pest than the gypsy moth, there has been hardly a complaint this year from its presence.

The sum total, then, of the discussion of these two pests is about as follows: It is possible to exterminate the gypsy moth and money expended to that end is well spent, and it can be kept out if once exterminated. The brown-tail we have no way of controlling by any mechanical means, and appropriations for fighting it must be devoted largely to such measures as are necessary for suppression. The work of suppression can, to a certain extent, be done as well by individuals as by the State, and as the gypsy moth demands immediate attention, the brown-tail can and should wait for consideration until sometime in the future when it will be absolutely necessary to deal with it.

How much of our territory is infested can not be accurately known. During the summer and fall, however, the insect has been reported from Woonsocket, East Providence, and Pawtucket. It has also been rumored that a few specimens have been found in Providence, but so far the infestation is not so very serious except perhaps in Pawtucket. One of the principal efforts of the State should be that of publishing such reports and accounts of the insect as shall enable

the people of the State to become thoroughly acquainted with it, so that they can make efforts to keep it in check on their property, should it occur. In accordance with this idea, a short descriptive account of the insect will here be given.

HISTORY AND DISTRIBUTION OF THE BROWN-TAIL MOTH.

This insect was imported into this country sometime after 1890, and was first noticed around Somerville, Massachusetts. It is not definitely known how it was brought over, but circumstances indicate that it was carried across the ocean on nursery stock. Like the gypsy moth, it attracted but little attention at first and was thought by the people of the district to be some native insect which had always been with them. In 1897, however, it had become such a destructive pest that it was brought to the attention of the gypsy moth workers and by them identified as the brown-tail moth so common in Europe. There was at that time no appropriation made for fighting anything but the gypsy moth, and consequently but little could be done except to ascertain the extent of the infested region. Precious time was therefore lost, and with it the hope of ever being able to exterminate the insect in this country. Later on a little money was appropriated for use against the pest, but it was merely sufficient to keep it partially in check in some of the thickly settled districts of the infested region. Since that time it has spread rapidly, until it has now been reported from the White Mountains in the north, eastward all along the coast of Maine into New Brunswick, south of Boston along Cape Cod Bay, into the eastern part of Rhode Island, and westward in Massachusetts to the Connecticut Valley. It is only a question of time when it will probably spread throughout the whole temperate region of North America.

It is a pest of no mean importance, owing especially to the irritative properties of some of the hairs, which will be mentioned later in the description of the insect. Infested districts have been made more or less uninhabitable to a great many people, and in some cases it has resulted in the reduction of real estate values and of property rentals

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