Bullet Powderpost Beetles

Family Bostrichidae. The bostrichidae beetle bores into the wood to lay their eggs. The polycaon is in this family and is the largest of the beetles in these two families.

The bark beetles, scolytidae, work between the bark and the sapwood of living trees and do not infest dead wood.

The flat headed borer, buprestidae, is attracted by smoke and is usually found in lumber that was involved in or close to forest fires. It is identified by the larvae having a flat wide head.

​The round headed borer are in the family cerambycidae (long horned beetles). There is the western pine borer, ergates. These are very large beetles, up to three inches long. The old house borer, hylotrupes, have up to a one quarter inch oval emergence hole. The larval stage may last from three to eleven years. These beetles will emerge through linoleum, asbestos shingles, aluminum siding and even ceramic tiles. The new house borer, arhopalus, has one quarter inch emergence holes, does not reinfest and leaves tunnels of tightly packed frass.

The family anobiide attack primarily in soft woods. They attack both sapwoods and heartwoods and they will attack hardwood. They seem to prefer wood weakened by fungus. They leave a course powder (frass) with pellets. The adult deathwatch beetle may have as long as a two year life cycle. The emergence holes are larger then lyctus beetles. The frass is courser than lyctus beetles. The larvae can live for as long as three years. With the deathwatch beetle, when viewed from above, the head is below the thorax.


DESCRIPTION: The bostrichid beetles normally have an enlarged prothorax (first body segment) which gives them a humpbacked appearance. The head of these beetles usually points straight down and is hidden from view by the large prothorax. Most bostrichids have a roughened thorax and their short antennae usually end in three or four enlarged segments. The black polycaon is totally unlike the majority of the bostrichids. It is 7/16 to 7/8 inch long, coal black with a prominent head that points straight out from the thorax. They have an oval prothorax, with coarse holes in it and the head. The wing covers have small holes.

Most bostrichids attack hardwoods, but a few species attack softwoods. They rarely attack and reinfest seasoned wood. The black polycaon is a typical bostrichid and can be 1/2 to 1 inch in length. The first signs of infestation are circular entry holes for the egg tunnels made by the females. The exit holes made by adults are similar, but are usually filled with frass. The frass is meal-like and contains no pellets. It is tightly packed in the tunnels, and does not sift out of the wood easily. The exit holes are round and vary from 3/32 to 9/32 inch in diameter. Bostrichid tunnels are round and range from 1/16 to 3/8 inch in diameter. If damage is extreme, the sapwood may be completely consumed. Bostrichids rarely cause significant damage in framing lumber and primarily affect individual pieces of hardwood flooring or trim. Replacement of structurally weakened members is usually the most economical and effective control method.

BIOLOGY: The black polycaon is found mainly in the far southwest and Pacific Coast states. These beetles prefer to infest softwoods. The leadcable borer is also most common along the Pacific Coast. The female bores into wood to form an egg gallery, as do all bostrichids. She lays eggs into pores in the wood as she moves in and out of the egg tunnel. The eggs hatch in about three weeks and the larvae feed on the wood for the next nine months. They bore parallel to the grain, filling their tunnels with meal like frass. The pupal stage lasts two weeks, but the new adults stay in the tunnel for four to six weeks before emerging. The adults chew their way out of the gallery and begin the life cycle all over again.

The leadcable borer is a more typical bostrichid. It is a cylindrical; brown, black or red-brown beetle; with red mouthparts, legs and antennae. The eight-segmented antennae have the last three segments greatly enlarged. The head is concealed by the hood-like prothorax which has many puncture-like holes in the front half. The wing covers have deep punctures arranged in a line.


Commonly called the Deathwatch beetle - approximately 1/4 inch long. Their pellets are bun shaped. Their color is brown to dark brown. They have an 11 segemented antenna with the last 3 segments larger. The adult deathwatch beetle is a little longer than 1/4 inch and is gray brown with yellow, scalelike hairs on the back of the body. These insects do not have the rows of pits on the elytra and their 11 segmented antennae end in three elongated segments that are as long as the previous five segments.

BIOLOGY: Furniture beetle adults emerge in the spring from cells just below the surface of the infested wood. Soon afterward, mating followed by egg laying takes place. The female lays the oval pearl-like eggs in old emergence holes, or cracks and crevices in the wood. Eggs hatch in six to 10 days and the larvae feed for about one year before pupating for two to three weeks. These insects infest both hardwoods and softwoods. The larvae normally follow the grain of the wood when feeding and fill their tunnels with cigar-shaped pellets of chewed wood.

Deathwatch beetles get their name from the habit the adults have of tapping their heads against the surface of the wood they are infesting. These beetles cannot infest wood unless it has been partially digested by fungi and therefore this beetle is most often found in poorly ventilated areas where the wood has a moisture problem. They prefer hardwoods such as oak but can move from these woods to softwoods.

Deathwatch beetle larvae are 7/16 inch long when mature, with tiny spines on the surface of the first eight abdominal segments. These beetles create large, "bun-shaped" pellets in their galleries.

DESCRIPTION: There are a large number of anobiid beetles that attack seasoned wood in the United States. These beetles range in size from less than 1/16 inch to over 5/16 inch long. They have highly variable body forms but they an almost have a "bellshaped" first body segment (pronotum) that hides the head when viewed from above.

The furniture beetle is 3/16 to 1/4 inch long, cylindrical and red-brown to dark brown. They have a series of pits in rows that run lengthwise on the wing covers. These pits can be seen through the fine yellow hairs that cover the body. Furniture beetles have segmented antennae, the last three segments of which are longer than the first eight combined. The larvae are gray- white and 1/4 inch long. The first seven abdominal segments have tiny spines on them. These spines are arranged in two rows running across the body on the first six segments, the seventh segment has only one row. Each spiracle (breathing hole) in the abdomen has a tubular projection attached to it. The last spiracle is not enlarged as it is in the lyctids.

Anobiid beetles. The most common anobiids attack the sapwood of hardwoods and softwoods. They reinfest seasoned wood if environmental conditions are favorable. Attacks often start in poorly heated or ventilated crawlspaces and spread to other parts of the house. They rarely occur in houses on slab foundations. Anobiids range from 1/8 to 1/4 inch in length and are reddish-­brown to nearly black. Adult insects are rarely seen. The most obvious sign of infestation is the accumulation of powdery frass and tiny pellets underneath infested wood or streaming from exit holes. The exit holes are round and vary from 1 /16 to 1/8 inch in diameter. If there are large numbers of holes and the powder is bright and light-colored like freshly sawed wood, the infestation is both old and active. If all the frass is yellowed and partially caked on the surface where it lies, the infestation has been controlled or has died out naturally. Anobiid tunnels are normally loosely packed with frass and pellets. It is normally 10 or more years before the number of beetles infesting wood become large enough for their presence to be noted. Control can be achieved by both chemical and non-chemical methods.


Lyctid powder-post beetles. Lyctids attack only the sapwood of hardwoods with large pores: for example, oak, hickory, ash, walnut, pecan, and many tropical hardwoods. They reinfest seasoned wood until it disintegrates. Lyctids range from 1/8 to 1/4 inch in length and are reddish-brown to black. The presence of small piles of fine flour-like wood powder (frass) on or under the wood is the most obvious sign of infestation. Even a slight jarring of the wood makes the frass sift from the holes. There are no pellets. The exit holes are round and vary from 1/32 to 1/16 inch in diameter. Most of the tunnels are about 1/16 inch in diameter and loosely packed with fine frass. If damage is severe, the sapwood may be completely converted within a few years to frass held in by a very thin veneer of surface wood with beetle exit holes. The amount of damage depends on the level of starch in the wood. Infestations are normally limited to hardwood paneling, trim, furniture, and flooring. Replacement or removal and fumigation of infested materials are usually the most economical and effective control methods.

DESCRIPTION: There are several species in the family lyctidae. Adult lyctid beetles vary in size from 1/16 to 5/16 of an inch long. They are brown, redbrown, or black with an easily seen prominent head. Antennae has eleven segments, tipped with a two-segmented head. Larvae are "C" shaped grubs that feed in the wood. Usually less than 3/16" long. The first body segment is enlarged.

BIOLOGY: Power post beetles attack seasoned woods such as oak, ash, hickory, bamboo and mahogany. Frass is a consistency of face powder and the color of the wood infested. Eggs are laid in the pores of hardwoods. Larvae feed on wood according to its starch content. Holes are round and approximately the size of a pin. Total development can take as long as two to four years.

Old house borer. The old house borer attacks only the sapwood of softwoods, primarily pine. It reinfests seasoned wood, unless it is very dry. The old house borer probably ranks next to termites in the frequency with which it occurs in houses in the Middle Atlantic States. The beetle ranges from 5/8 to I inch in length, and is brownish-black in color. The first noticeable sign of infestation by the old house borer may be the sound of larvae boring in the wood. They make a rhythmic ticking or rasping sound, much like a mouse gnawing. In severe infestations the frass, which is packed loosely in tunnels, may cause the thin surface layer of the wood to bulge out, giving the wood a blistered look. When adults emerge (3 to 5 years in the South; 5 to 7 years in the North), small piles of frass may appear beneath or on top of infested wood. The exit holes are oval and 1/4 to 3/8 inch in diameter. They may be made through hardwood, plywood, wood siding, trim, sheetrock, paneling, or flooring.

The frass is composed of very fine powder and tiny blunt-ended pellets. If damage is extreme, the sapwood may be completely reduced to powdery frass with a very thin layer of surface wood. The surfaces of the tunnels have a characteristic rippled pattern like sand over which water has washed. Control can be achieved by both chemical and non-chemical methods.