- Hylurgopinus rufipes, or the native elm bark beetle, is approximately .18 inches long, and its brownish-black body is covered in bristly yellow hair. The smaller European elm bark beetle (Scolytus multistriatus) is approximately .13 inches long and has a brown head and reddish-brown body. Banded elm bark beetles (Scolytus schevyrewi) are native to Asia and Russia. They're around .11 inches long and have brown bodies with darker bands across their wing covers. All three species lay eggs that hatch into legless, C-shaped, creamy-white larvae.
- Native and smaller European elm bark beetles feed on healthy branches and lay their eggs in diseased or dying branch bark. Their larvae create galleries by tunneling into the bark, leaving wounds in the wood. Banded elm bark beetles feed on young twig tissue, and females dig holes in healthy bark to lay their eggs. Their larvae feed on the phloem, or the tissue below the bark that carries nutrients to the rest of the tree. Although native and smaller European elm bark beetles can weaken trees and contribute to their demise, they rarely are the direct cause of tree death. Severe infestations of banded elm bark beetles, however, can kill trees.
- Native and smaller European elm bark beetles are confirmed agents of Dutch elm disease, and researchers suspect that banded elm bark beetles may also vector the pathogen. The Dutch elm fungus produces sticky spores that stick to adult beetles, and the beetles spread the Ophiostoma ulmi and Ophiostoma novo-ulmi fungi that cause Dutch elm disease when they move from diseased to healthy trees. Dutch elm disease causes yellowing and browning in the foliage and discolors the inner sapwood, eventually causing tree death.
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