![File:1989. Pitch tubes in response to mountain pine beetle attack. (36317742366).jpg - Wikimedia Commons File:1989. Pitch tubes in response to mountain pine beetle attack. (36317742366).jpg - Wikimedia Commons](https://upload.wikimedia.org/wikipedia/commons/a/a8/1989._Pitch_tubes_in_response_to_mountain_pine_beetle_attack._%2836317742366%29.jpg)
File:1989. Pitch tubes in response to mountain pine beetle attack. (36317742366).jpg - Wikimedia Commons
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Bnineteenteam Chromatisches 13-Töne-Stimmgerät C-C für Pitch Pipe mit Etui für Musikinstrumente Musikinstrumentenzubehör : Amazon.de: Musikinstrumente & DJ-Equipment
![Pitch tubes on a ponderosa pine tree resulting from attack by mountain... | Download Scientific Diagram Pitch tubes on a ponderosa pine tree resulting from attack by mountain... | Download Scientific Diagram](https://www.researchgate.net/publication/259601633/figure/fig17/AS:650039332450336@1531992862585/Pitch-tubes-on-a-ponderosa-pine-tree-resulting-from-attack-by-mountain-pine-beetle.png)