This beetle is now well established in this country and is a most serious furniture pest. The adults eat holes through heavy leather and linen coverings, while the larvæ reduce the hair used in the upholstering to a mass of cast larval skins and ground-up hair. The hair then has the appearance of black gritty dirt which can be scraped up by the handful, if not by the pailful. When the larvæ become abundant in a piece of furniture they may drop to the floor and there feed upon rugs and other fabrics made of wool, hair, fur, or feathers. The larva; or grubs are seldom seen unless searched for, but the adults, because of their habit of flight during March to June (in Washington), leave the furniture and crawl about the furnishings and windows, and while hardly one-fourth of an inch long, are made conspicuous by the brown, white, and yellow scales that cover their bodies.
For a general impression of the appearance of the furniture carpet beetle see Figure 10. The adult may live several weeks. The female has been known to lay as many as 36 eggs in one day. Fortunately this species does not seem to be very prolific, since no adult has been known to lay more than 85 eggs. The eggs are small, white, easily crushed by brushing, and are laid in the nap of clothing. In furniture coverings of mohair, plush, and similar materials the eggs are tucked down in the pile, as shown in Figure 13. The eggs hatch during warm summer weather in from 12 to 15 days. The larvæ require the rest of the year for growth and do not transform to the adult until the following spring. The larvæ, however, do not all grow equally well, and some specimens may require only one year for development, while others may remain for considerable periods somewhat dormant, even in the presence of much food, and will not transform to the adult until much later, sometimes as long as one year after others, hatching on the same day, have matured.
CONTROL MEASURES.
The measures to be used for the control of carpet beetles depend upon the place in the house where the pest is causing injury. If carpet beetles are troublesome in trunks, chests, or closets that are not opened often, a good grade of flake naphthalene, paradichlorobenzene or camphor will give good results. If the trouble is in closets in daily use, beneath carpets or rugs, or in piano felts or upholstered furniture, these substances are of practically no value, and one must fumigate the house as a whole or in part with either hydrocyanic-acid gas, carbon disulphid, or carbon tetrachlorid, or use the still older, more tedious, and less effective means of control consisting in frequent search for and the killing of the individual larvæ and adults, and the treatment of floor cracks and similar hiding places with kerosene, gasoline, or benzine. The following materials and methods may be employed with satisfactory results:
NAPHTHALENE.
Naphthalene in the form of flakes (preferably) or moth balls is effective when used at the rate of one-half to 1 pound to each 10 to 13 cubic feet of space. It is always better to use a larger rather than a smaller quantity of these crystals Great care should be exercised to keep tightly closed the trunks or chests of clothing with which the naphthalene is stored. Naphthalene in chests opened frequently or those carelessly left open for hours at a time, or in chests with large cracks or warped covers, is not to be depended upon. Naphthalene should be of good grade. It is best to purchase it put up in unbroken tin cans of 1 pound or more capacity. Remember that naphthalene kills all stages of the carpet beetles by means of the fumes given off during the slow evaporation of its crystals and it is essential that these fumes be closely confined. Naphthalene in bureau drawers, in closets frequently used, scattered upon closet shelves, or beneath carpets is not to be depended upon for absolute protection.
PARADICHLOROBENZENE.
Paradichlorobenzene crystals are similar in general appearance to those of naphthalene. The fumes given off by the slow evaporation of the crystals in a tightly closed container will kill all stages of the carpet beetle, if about 1 pound of crystals is used for each 10 cubic feet of space.
CAMPHOR.
Camphor is not as quickly effective against all stages of carpet beetles as are naphthalene and paradichlorobenzene. Its action is slower. Use from one-half to 1 pound for each trunk of about 10 cubic feet capacity.
RED-CEDAR CHESTS.
Chests made of red cedar, popularly known as Virginia or Tennessee red cedar, if well constructed, will kill the very young larvæ of carpet beetles. They will not kill the beetles, the older larvæ, or the pupae, nor will they prevent the eggs from hatching. The writer has known larvæ of the black carpet beetle to remain apparently unaffected in a red-cedar chest from June of one year to May of the following year, and then to transform normally to the adult stage. The older larvæ of carpet beetles can be removed from clothing before it is stored in chests by thorough brushing. It is valuable to know that red-cedar chests will kill the very young larvæ. It should always be remembered that articles such as balls of yarn, floor skins backed with woolen cloth, pillows stuffed with hair or feathers, and similar objects in the interior of which the older carpet-beetle larvæ can hide should not be placed in cedar chests until fumigated to kill the larvæ hidden where they can not be reached by brushing.
Juniperus virginiana.
Attagenus piceus.
COLD STORAGE.
One of the safest methods of preventing loss through carpet-beetle attack is to store susceptible articles with a reliable cold-storage firm maintaining rooms for such purposes at a temperature of 50° F. or lower.
FUMIGATION.
Carpet beetles, as well as all other household pests, can be eliminated as disturbing factors by fumigation within as short a time as three or four hours (if necessary). Fumigation with formaldehyde candles, although excellent for killing disease germs, is worthless for insect control, and the public is warned accordingly. Sulphur fumes will kill many carpet beetles, but very few persons succeed in killing all carpet beetles with sulphur fumes. Sulphur should be burned at the rate of 13½ ounces per 1,000 cubic feet of space. It is likely to bleach wall paper and fine fabrics and tarnish metals, and should never be used unless one is aware of these possible bad results.
=Hydrocyanic-acid gas.=--Hydrocyanic-acid gas is the best gas known and in present use for the fumigation of houses, or parts of houses, for the speedy elimination of carpet beetles or other pests. When persons are troubled with fabric pests that have become generally established throughout the house, nothing will give greater satisfaction in peace of mind and freedom from trouble than one thorough fumigation carried on by a professional fumigator or by any intelligent, careful person capable of following directions. Hydrocyanic-acid gas is dangerous to human beings, but is noninflammable and nonexplosive as used in household fumigation as here advocated. It is lighter than air, will injure no fabric or painting, and will not tarnish household metals. If properly used, it is one of the simplest and best methods of fighting house pests. Interested persons can have full particulars free of cost by writing the Division of Publications, Department of Agriculture, for Farmers' Bulletin 699.
=Carbon disulphid.=--Carbon disulphid is a fumigant in general use for killing insects of all sorts in containers that are reasonably tight. It is excellent for killing carpet beetles in chests, trunks, and closets that can be closed and sealed. It has been used for the fumigation of entire buildings when these are detached. It is purchased at drug stores or of chemical firms as a liquid put up in tin cans containing 1, 2, 5, or 10 pounds each. Upon exposure to the air, the liquid evaporates, forming a gas heavier than air which sinks through the container being fumigated and kills the insects by suffocation. The gas is explosive in the presence of fire, and must be handled with the same care as gasoline or benzine. Although the liquid as purchased is considered not explosive or inflammable, great care should be exercised in storing and handling it since it is almost impossible to dissociate it from its gas, which is, as stated above, decidedly explosive and inflammable in the presence of fire. The odor of carbon disulphid gas is very disagreeable, but soon disappears with the airing of the container after fumigation. Carbon disulphid fumigation is excellent for the destruction of carpet beetles in articles that can be stored in trunks, chests, or closets, or for killing pests in pianos and upholstered furniture that can be placed in a small room for the period of fumigation. Full particulars regarding this fumigant and the ease with which it can be used may be had by writing the Division of Publications, Department of Agriculture, for Farmers' Bulletin 799.
=Carbon tetrachlorid.=--Carbon tetrachlorid is used in exactly the same way and for the same purpose as carbon disulphid, except that from two to three times as much of the liquid must be used to fumigate the same amount of space. Carbon tetrachlorid is not a particularly effective fumigant, but it has the advantage of producing, upon evaporation, a gas that is noninflammable and nonexplosive, and for this reason can be used in certain places where lighted lamps, fires, etc., can not be entirely eliminated. See Farmers' Bulletin 799 for reference to use of carbon tetrachlorid and carbon disulphid.
MISCELLANEOUS CONTROL MEASURES.
=Laundering and dry cleaning.=--When material infested with carpet beetles is submerged in a solution of 1 pound of neutral soap to 10 gallons of water all stages of the beetles are killed. Carpet-beetle larvæ are killed if subjected to temperatures of 120, 125, and 128° F. for 30, 15, and 10 minutes, respectively. Eggs are killed when subjected to temperatures of 125 and 130° F. for 16 and 11 minutes, respectively Eggs and larvæ were killed in material dipped for 5 second in water at 140° F., but submergence for the same period in water at a temperature of 122° F. failed to kill all of them. Translated into household terms this means that laundering clothing or other textiles in thick suds or with water hotter than the hand can bear, or pressing with a hot iron, will probably kill the larvæ and eggs of the carpet beetle. The usual commercial dry-cleaning processes also are probably effective. Unfortunately these methods are not always easily applied to the articles most likely to be infested; they must not be considered a preventive against reinfestation.
=Treatment of floor cracks and other hiding places.=--Carpet-beetle larvæ often secrete themselves in the cracks of flooring, beneath base boards, and in other openings about houses formed by the usual shrinking or settling of woodwork. The larvæ feed upon the lint which gathers in such places. It is, therefore, an excellent procedure to have all such openings closed where possible by filling in with putty or patented crack-fillers. Any cracks that can not be filled in this manner should be periodically filled with gasoline, kerosene, or benzine to kill larvæ. Since these liquids are inflammable, care must be exercised not to have lighted lamps or fire in any form about until after the rooms are well ventilated.
ORGANIZATION OF THE UNITED STATES DEPARTMENT OF AGRICULTURE.
Secretary of Agriculture Henry C. Wallace. Assistant Secretary C. W. Pugsley. Director of Scientific Work E. D. Ball. Director of Regulatory Work Weather Bureau Charles F. Marvin, Chief. Bureau of Agricultural Economics Henry C. Taylor, Chief. Bureau of Animal Industry John R. Mohler, Chief. Bureau of Plant Industry William A. Taylor, Chief. Forest Service W. B. Greeley, Chief. Bureau of Chemistry Walter G. Campbell, Acting Chief. Bureau of Soils Milton Whitney, Chief. Bureau of Entomology L. O. Howard, Chief. Bureau of Biological Survey E. W. Nelson, Chief. Bureau of Public Roads Thomas H. MacDonald, Chief. Fixed Nitrogen Research Laboratory F. G. Cottrell, Director. Division of Accounts and Disbursements A. Zappone, Chief. Division of Publications Edwin C. Powell, Acting Chief. Library Claribel R. Barnett, Librarian. States Relations Service A. C. True, Director. Federal Horticultural Board C. L. Marlatt, Chairman. Insecticide and Fungicide Board J. K. Haywood, Chairman. Packers and Stockyards Administration { Chester Morrill, Assistant Grain Future Trading Act Administration { to the Secretary. Office of the Solicitor R. W. Williams, Solicitor.
This bulletin is a contribution from
Bureau of Entomology L. O. Howard, Chief. Stored-Product Insect Investigations E. A. Back, Entomologist in Charge.
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