form a neck. Larvae are also elongate and slender, with globular heads. They bore 
deeply into timbers, causing pinhole defects—small tunnels across the grain having 
dark, stained walls. 
The chestnut timberworm, Melittomma sericeum (Harris), once a destructive 
pest of chestnut, 1s now found chiefly in white oak. The nocturnal adults are brown, 
clothed with fine silky hair, and are 11 to 15 mm long. Eggs are laid in cracks in the 
wood surface. 
The sapwood timberworm, Hylecoetus lugubris Say, 1s a reddish-brown or 
blackish beetle 10 to 12 mm long. Eggs are laid from April to July on bark of dying 
trees or unseasoned logs. Larvae bore across the grain of the sapwood of various 
hardwoods, such as poplar, birch, yellow-poplar, basswood, buckeye, and black 
walnut. The larvae have a distinguishing feature, a conical, slender, barbed spine on 
the ninth segment. 
Family Mordellidae 
Tumbling Flower Beetles 
Adults of this family can be recognized by their habit of jumping or tumbling off 
flowers and by their characteristic strongly arched, wedge-shaped bodies that 
usually end in a long, conical process. They are usually black or dark brown, often 
spotted or banded with yellow or silver, and from 3 to 7 mm long. The head is bent 
downward, and the hindlegs are long, flattened, and spiny. The larvae of many 
species feed in rotting wood; some species are reportedly predacious. 
Beetles That Damage Seasoned Wood 
Numerous beetle species may damage seasoned wood in storage or use. Beetle 
larvae bore meandering, powder-filled feeding tunnels within wood, and the adults 
chew small round or oval holes in the surface of wood as they emerge. Adults of a 
few species bore short tunnels into wood for egg laying. When heavily infested or 
repeatedly attacked over an extended period, wood is often reduced to a mass of 
powder surrounded by a thin shell of sound wood perforated with holes. Damage of 
this type has commonly been termed “powderpost.”’ 
Beetles that cause a powderpost type of damage to wood are, as a group, ignored 
and misunderstood by many entomologists, foresters, and wood users. Damage, 
superficially similar in appearance, may be caused by numerous species within the 
families Anobiidae, Lyctidae, Bostrichidae, Ptinidae, Curculionidae (subfamily 
Cossoninae), and a few species within the families Cerambycidae and 
Oedemeridae. Many of these beetles can reinfest wood after it is dry, although some 
require wood in a very moist condition (Oedemeridae, Cossoninae weevils, and 
Ptinidae) and with bark attached (most Bostrichidae). 
Seasoned wood may also contain damage from various other beetles within the 
families Buprestidae, Cerambycidae, Platypodidae, and Scolytidae. Although 
adults initiate the attacks in the moist wood of trees recently dead or dying or in 
drying logs and lumber, larvae may complete their development in wood after it is 
dry. These beetles, but not necessarily their damage, are usually removed during 
wood processing; damage is frequently misidentified as that of beetles capable of 
reinfesting dry, seasoned wood. Occasionally, adults may emerge from air-dried 
wood after it is in use. Additionally, larvae of the families Dermestidae, Ten- 
ebrionidae, and nonwood feeding Anobiidae occasionally use wood as a pupation 
site. 
Fortunately, the numerous beetles that damage seasoned wood may be identified 
to group by characteristics of habits and damage. The incidence and location of 
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