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Powderpost beetles are a group of seventy species of
woodboring beetle
The term woodboring beetle encompasses many species and families of beetles whose larval or adult forms eat and destroy wood (i.e., are xylophagous). In the woodworking industry, larval stages of some are sometimes referred to as woodworms. The ...
s classified in the
insect
Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pairs ...
subfamily Lyctinae.
These beetles, along with
spider beetle
Spider beetles make up the subfamily Ptininae, in the family Ptinidae. There are approximately 70 genera and 600 species in the subfamily, with about 12 genera and 70 species in North America north of Mexico.
Spider beetles have round bodies wi ...
s,
death watch beetle
The deathwatch beetle (''Xestobium rufovillosum'') is a species of woodboring beetle that sometimes infests the structural timbers of old buildings. The adult beetle is brown and measures on average long. Eggs are laid in dark crevices in old w ...
s,
common furniture beetle
The common furniture beetle or common house borer (''Anobium punctatum'') is a woodboring beetle originally from Europe but now distributed worldwide. In the larval stage it bores in wood and feeds upon it. Adult ''Anobium punctatum'' measure in ...
s,
skin beetles, and others, make up the superfamily
Bostrichoidea. While most woodborers have a large
prothorax
The prothorax is the foremost of the three segments in the thorax of an insect, and bears the first pair of legs. Its principal sclerites (exoskeletal plates) are the pronotum (dorsal), the prosternum (ventral), and the propleuron (lateral) on ea ...
, powderpost beetles do not, making their heads more visible. In addition to this, their antennae have two-jointed clubs. They are considered
pests
PESTS was an anonymous American activist group formed in 1986 to critique racism, tokenism, and exclusion in the art world. PESTS produced newsletters, posters, and other print material highlighting examples of discrimination in gallery represent ...
and attack
deciduous trees
In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, aft ...
, over time reducing the wood to a
powdery dust. The damage caused by
longhorn beetles
The longhorn beetles (Cerambycidae), also known as long-horned or longicorns, are a large family of beetles, with over 35,000 species described. Most species are characterized by extremely long antennae, which are often as long as or longer than ...
(family Cerambycidae) is often confused with that of powderpost beetles, but the two groups are unrelated. The
larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle.
The ...
e of the Cerambycidae are white, straight and generally flat-headed, whereas those of the Bostrichidae are white and C-shaped.
Name
The term "powderpost" comes from the fact that the larvae of these beetles feed on
wood
Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulose fibers that are strong in tension and embedded in a matrix of lignin th ...
and, given enough time, can reduce it to a mass of fine powder. Because of this behavior, they are considered pests. These beetles can survive in colder climates.
Life cycle
Powderpost beetle larvae spend months or years inside
wood
Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulose fibers that are strong in tension and embedded in a matrix of lignin th ...
while developing, feeding mainly on the starch content. Their presence is only apparent when they emerge as adults, leaving behind pinhole-sized openings, often called "shot holes".
They may also leave piles of powdery
frass
Frass refers loosely to the more or less solid excreta of insects, and to certain other related matter.
Definition and etymology
''Frass'' is an informal term and accordingly it is variously used and variously defined. It is derived from the ...
below. Shot holes normally range in diameter from to , depending on the species of beetle. If wood conditions are right, female beetles may lay their eggs and re-infest the wood, continuing the cycle for generations.
Target materials
Powderpost beetles feed on
deciduous trees
In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, aft ...
, including certain
hardwood
Hardwood is wood from dicot trees. These are usually found in broad-leaved temperate and tropical forests. In temperate and boreal latitudes they are mostly deciduous, but in tropics and subtropics mostly evergreen. Hardwood (which comes from ...
s or
softwood
file:Pinus sylvestris wood ray section 1 beentree.jpg, Scots Pine, a typical and well-known softwood
Softwood is wood from gymnosperm trees such as conifers. The term is opposed to hardwood, which is the wood from angiosperm trees. The main diff ...
s depending on the species. Some hardwoods are naturally immune if they have low starch content or if their pore diameters are too small for the female beetle's
ovipositor
The ovipositor is a tube-like organ used by some animals, especially insects, for the laying of eggs. In insects, an ovipositor consists of a maximum of three pairs of appendages. The details and morphology of the ovipositor vary, but typical ...
to lay her eggs in.
Wood preservatives
Wood easily degrades without sufficient preservation. Apart from structural wood preservation measures, there are a number of different chemical preservatives and processes (also known as "timber treatment", "lumber treatment" or "pressure treat ...
can be used to prevent beetle infestation. Common treatments may use
borate
A borate is any of several boron oxyanions, negative ions consisting of boron and oxygen, such as orthoborate , metaborate , or tetraborate ; or any salt with such anions, such as sodium metaborate, and disodium tetraborate . The name also refe ...
, and frequently structural
fumigation
Fumigation is a method of pest control or the removal of harmful micro-organisms by completely filling an area with gaseous pesticides—or fumigants—to suffocate or poison the pests within. It is used to control pests in buildings (s ...
.
Items that can be infested by powderpost beetles include wooden tools or tool handles, frames, furniture, gun stocks, books, toys, bamboo, flooring, and structural timbers.
References
Bibliography
*
External links
*
*
Lyctinae at Fauna EuropaeaPowderpost Beetle Fact Sheetfrom the National Pest Management Association with information on habits, habitat and prevention
at the
National Park Service
The National Park Service (NPS) is an agency of the United States federal government within the U.S. Department of the Interior that manages all national parks, most national monuments, and other natural, historical, and recreational propertie ...
.
Powderpost beetles – The other, other wood destroying insectsfrom Michigan State University Extension.
the effect of beetles on wooden structures.
{{Taxonbar, from=Q2638541
Bostrichidae
Building defects
Household pest insects
Woodboring beetles