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Trap Tree Method for Controlling the Engelmann Spruce Beetle in Colorado

No digital file available.
Please contact Special Collections for access.

Citation

Nagel, R. H., David McComb, and F. B. Knight. 1957. “Trap Tree Method for Controlling the Engelmann Spruce Beetle in Colorado.” Special Collections, USDA National Agricultural Library. Accessed October 29, 2026, https://www.nal.usda.gov/exhibits/speccoll/items/show/4384.