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Pole Borer – Aberrant Wood Borer – Parandra brunnea

Pole Borer/Aberrant Wood Borer (Parandra brunnea) Latin Name: Parandra brunnea (Saussure) Common Name: Pole Borer/Aberrant Wood Borer Appearance:
  • The adult insect is normally 18-20 mm long, although the size varies widely (10-22 mm) depending on food during the larval stage. They are reddish-brown and have large jaws that protrude forward.
  • The pole borer’s antennae are not especially lengthy compared to other members of its family (Cerambycidae), known as longhorned beetles. It is also referred to as the “aberrant wood borer” because of these and other behaviors.
  • Larvae are cream-colored “roundheaded borers” with elongated bodies and a tiny blackhead with pronounced mandibles. They are typically seen riddling the inside of decaying tree trunks, creating oval-shaped tunnels.
Host plants: Willow, maple, elm, poplars, and various other hardwoods have been identified as hosts. Pole borer has also been observed attacking conifers. Territory: Native to North America Damage caused by Pole Borer: The pole borer develops as a normal roundheaded borer digging into the wood. Attacks on live trees are nearly always limited to the plant’s base, frequently starting at wounds where the sapwood has been exposed. Repeated bites of this insect, in conjunction with wood-decaying fungi, usually result in the honeycombing of the wood within a few years. Larval tunnels can severely plague the wood, causing it to collapse or shatter during a storm. This bug has also caused damage to telephone poles and timbers in touch with the soil, earning it the name “pole borer.” Life history and Habits: Adults are active in the middle of the summer. Females implant eggs into regions of deadwood during early assaults, sometimes in clusters of up to a dozen eggs at a time. The larvae, a species of round-headed borer, can take up to three years to mature and create a tunnel several feet long. They pupate in cells at the end of larval tunnels and often emerge to mate and launch fresh assaults. However, as the infestation spreads, some adults may remain in the tree, mating and laying eggs within the galleries of existing tunnels. Previous escape holes are also exploited by migrating adults visiting a previously afflicted tree.