TA Arv 2. LIBRARY
STATE PLANT BOARD
E-472 April 1939
United States Department of Agriculture
Bureau of Entomology and Plant Quarantine
THE EUROPEAN EARWIG AND ITS CONTROL*
By C. W. Getzendaner,
Division of Truck Crop and Garden Insect Investigations
The European earwig (Forficula auricularia L.) has been reported as a
pest from Massachusetts, Rhode Island, New York, Colorado, Idaho, Utah,
Washington, Oregon, and California. The adult insects are about three-
quarters of an inch in length, of a reddish-brown color, and bear a pair of
prominent forceps on the rear end of the body, those of the male being
Earwigs forage at night and hide in dark places during the day. They
feed on a wide variety of plants and also on various small insects, particu-
larly aphids. Leaves and flowers of zinnia, dahlia, hollyhock, and butterfly
bush are severely damaged, and the insect befouls lettuce, celery, Swiss
chard, sweet corn, and other vegetables which provide a hiding place for it.
Ripe fruit also serves as food, and peaches and apricots are especially
attractive. Usually the earwig is not highly destructive to vegetation and
tends to avoid cultivated areas. Often it enters houses, where it is a
menace to health because of its unsanitary and filthy habits.
Since earwigs collect in dark places during the daytime, they may be
trapped with various special devices made for that purpose and then de-
stroyed, but the most effective remedy is a poisoned bait made up as follows:
Bran...................................... 12 pounds
Sodium fluosilicate ........ 1 quart
Fish oil.............................. 1 quart
If sodium fluosilicate is not obtainable, sodium fluoride, barium
fluosilicate, or paris green may be substituted at the above dosage, but
these are not so effective as the poison recommended. Commercially prepared
bait mixed according to the above formula is obtainable from insecticide
dealers in many of the localities infested by the European earwig in the
This supersedes Circular E-282, The European Earwig, by S. E. Crumb,
which was issued in April 1932.
UNIVERSITY OF FLORIDA
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Mix the dry bran and poison very thoroughly, add the fish oil and
mix thoroughly again. Do not use water. The quantity of bait in the fore-
going formula is sufficient for making one application. Broadcast thinly
over an area of approximately 8,000 square feet. Apply the bait to the
entire premises, and give particular care to scattering it along or at the
base of fences, shrubbery, trees, telephone poles, wood piles, and other
places frequented by earwigs. Take care to avoid getting the bait on the
foliage of flowering plants and shrubs, since under certain conditions the
ingredients in the bait may cause foliage injury. Do not sprinkle lawns
where the bait has been applied until at least two nights have elapsed.
The bait should be kept out of reach of children and pets, and its
use in poultry yards is not advised, although chickens can eat a large quan-
tity of the bait before ill effects are noticeable. Where the presence of
poultry or game birds makes it inadvisable to broadcast the bait, it may be
placed in boxes perforated with a few small holes to allow the earwigs to
Earwigs wander about a great deal under some conditions, and where the
bait is applied to only a single house lot or other small area located within
a larger infested area it may become reinfested very soon. The best results,
therefore, are obtained through cooperative campaigns wherein the bait is
broadcast throughout several city blocks or larger areas.
Imported parasites of the European earwig have been released in many,
localities of Washington, Oregon, Rhode Island, and Massachusetts, to prey :
upon the earwigs, and indiscriminate scattering of the poison bait in such ,
localities would interfere with the work of these parasites. It is sug- '
tested, therefore, that the bait be applied before the middle of May, o;,. ,
if earwigs are not abundant prior to that time, that the application of tha -:4
bait be deferred to the last week of July and the first week of August, dur- *:||,,==`
ing which time fewer of the beneficial parasites will be affected.
Where to Obtain Insecticides
Information regarding the purchase of the insecticide materials men-
tioned in this circular may be obtained usually through local dealers in .'' ...
agricultural supplies, seedsmen, general stores, drug and department stores, .|
or through the county agricultural agent, State agricultural experiment *
station, State department of agriculture, or Bureau of Entomology and Plant ;
Quarantine, U. S. Department of Agriculture.