Hello Patrck,

That is a male Whitespotted Pine Sawyer, Monochamus scutellatus (Coleoptera: Cerambycidae).

The whitespotted pine sawyer is a native longhorn beetle. The genus Monochamus is represented by several wood-boring beetle species in the eastern U.S., all of which feed on various conifers. The most common species in our area are M. scutellatus and the northeastern sawyer, M. notatus. The larvae are known as "sawyers" because of the loud noise they make while feeding. Freshly cut, felled, dying or recently dead trees are preferred. Young larvae feed on the inner bark, cambium and outer sapwood, forming shallow excavations called surface galleries that they fill with coarse, fibrous borings and frass (insect excrement). As they grow older, they bore deep into the heartwood, and then turn around and bore back toward the surface, thereby forming a characteristic U-shaped tunnel. A pupal cell is formed at the outer end of the tunnel, from which the adult emerges by chewing through the remaining wood and bark. Eggs are laid in slits or niches chewed in the bark, preferable near old branch scars or in wrinkled areas on logs. Full-grown larvae are often close to 2 inches long. Two years are required to complete the life cycle in the Lake States and southern Canada. Members of the genus often cause heavy losses in wind-thrown or fire-killed timber, in saw logs left too long in the woods or left too long with the bark on before milling, and in improperly handled pulpwood. Adult beetles are vectors of Pinewood nematode. Debarking logs immediately after felling the trees is highly effective in reducing sawyer damage to logs.

Regards,
Howard

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