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Hungry for more stories on science, culture and technology?Check out Brain Food: Insights and Discoveries from Northern Arizona. From ground breaking scientific research to global music projects, Brain Food profiles some of the unique projects happening in the region and the interesting people behind them. While there are no new episodes of Brain Food, we will continue to maintain the archive here.

Brain Food: NAU Bark Beetle Researcher Fights Back With Fungus

KNAU/Bonnie Stevens

Growing microscopic organisms in a lab to conduct biological warfare might sound like the makings of a science fiction movie. But in the case of the bark beetle, it's real. An entomologist at Northern Arizona University is using a fungus to combat the beetles' deadly attack on forests across the West. As Arizona Public Radio's Bonnie Stevens reports, the fungus is the latest in a string of unconventional methods to stop the bugs' rampage.

Entomologist Rich Hofstetter will do anything to get rid of bark beetles. He's tried blowing their minds with Rock n' Roll and amplifying their own sounds to try and drive them crazy. Now, he's using a forest fungus to destroy the bugs from the inside out.

"The spores of the fungus penetrate the exoskeleton of the beetle," Hofstetter says. "Once they get inside, they replicate, they grow, and it kills the beetle within 1 or 2 days".

Hofstetter is one of the world's leading bark beetle researchers. In his lab at NAU, he keeps an impressive collection of the troublesome insects: he's got bark beetles in jars, bark beetles pinned to boards, bark beetles in Petri dishes. This is where he's conducting groundbreaking research on a fungus called Bavaria Basiana. Hofstetter believes it could be instrumental in stopping bark beetles from annihilating forests.

"This fungus we're working on is a natural native fungus that naturally kills bark beetles," he says. "We've isolated particular strains, and we're testing to see whether these strains are effective against not only the mountain pine beetle - which is the most significant bark beetle in the West - but all the other bark beetles that we have in Arizona that are killing trees, and in the eastern U.S. as well."

Arizona has been hit hard by bark beetles. In 2003, after years of drought and a changing climate, the bugs infested more than 1,000,000 acres of pine, fir and other trees. Pesticide treatments have been used in small areas, like parks and campgrounds. But, the fungus Hofstetter is researching would be the first natural insecticide to be used on large swaths of forest. He describes the fungus as "a white, fluffy substance". Hofstetter says, "it looks like cotton, and if you look really close, you'll see tiny spores that are then transmitted through the air or picked up by other insects."

Credit KNAU/Bonnie Stevens
Entomologist Rich Hofstetter tests out his "fungal spray" on a ponderosa pine at NAU

Hofstetter grows the spores in his lab and then turns them into a liquid solution. To test its effectiveness, he sprays it on logs and adds a handful of bark beetles.

"Within a few days, " he says, "we go back and see whether the insect has died, what percentage of the insects have died because of the fungus."

So far, it's about 90%. That's a better success rate than Hofstetter's earlier attempts to blast the beetles out of trees with loud music. And spraying the destructive bugs is much more realistic than hanging tiny speakers in a million acres of forest.

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