Douglas-fir Beetle vs Japanese Rhinoceros Beetle (Blue)

Side-by-side species comparison

Attribute Douglas-fir Beetle Japanese Rhinoceros Beetle (Blue)
Scientific Name Dendroctonus pseudotsugae Trypoxylus dichotomus septentrionalis
Order Coleoptera Coleoptera
Family Curculionidae Dynastidae
Size 4-6 mm 35-70 mm
Habitat Mountains Grasslands
Diet Wood Feeders Sap Feeders
Regions Western North America from British Columbia to Mexico East Asia, Japan (Hokkaido)
Conservation Least Concern Least Concern

Douglas-fir Beetle

A dark reddish-brown bark beetle that attacks Douglas-fir trees, particularly those weakened by drought or windthrow. It is among the most damaging bark beetles in the Pacific Northwest.

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Did You Know?

It preferentially attacks fallen or stressed trees, but during outbreaks it can kill large numbers of healthy standing trees.

Japanese Rhinoceros Beetle (Blue)

The northern Japanese subspecies of the rhinoceros beetle, found in Hokkaido. Slightly smaller and darker than mainland populations, adapted to cooler climates with a shorter active season.

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Did You Know?

Hokkaido rhinoceros beetles emerge later in summer than their southern relatives and have a compressed breeding season due to the shorter northern summer.