Any member of the beetle family Scolytidae, many of which severely damage trees. Bark beetles are cylindrical, brown or black, and usually less than 0.25 in. (6 mm) long. A male and females (as many as 60 females with each male) bore into a tree and form a chamber where each female deposits her eggs. The emerging larvae bore away from the chamber, forming a characteristic series of tunnels. Different species attack particular trees, damaging roots, stems, seeds, or fruits. Some species transmit disease (e.g., elm bark beetles carry spores of the fungal Dutch elm disease).

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