Pawpaw trees, which grow Ohio’s largest native fruit, are resistant to a lot of pests: Many insects, rabbits and deer largely leave the understory plant alone.
But in recent years, invasive ambrosia beetles have been wreaking havoc on pawpaw trees in parts of southeast Ohio.
“It's been pretty tough,” said Chris Chmiel, a co-owner of Integration Acres. The farmstead near Athens is one of the largest pawpaw processors in the world.
Ambrosia beetles drill through a tree’s bark and then cultivate a fungus, which both adult beetles and their larvae feed on. Some are native to the region and primarily target stressed and weakened trees. But recently, invasive ambrosia beetles have been causing more widespread damage.
“When that happens, the branches at the tips, they start to wither and slowly you see that the trees die over a one- to two-year period,” Chmiel said. “And the only thing you can really do about it is cut your trees down and burn the wood and then start over.”
He estimates the invasive beetles have killed around 75% of the pawpaw trees in his orchard.
Replanting and moving forward
Chmiel started growing pawpaws in the ‘90s and now uses their tropical-tasting fruit to produce a range of pawpaw-flavored products, from pulp to fudge.
In the past 30 years, he’s seen the fruit explode in popularity.
“When people get a chance to try it, I think oftentimes people love it,” he said.
His business has blossomed, but around seven or eight years ago, the region experienced a particularly rainy spring.
“[Pawpaws] don't like to have their roots submerged in water for long,” Chmiel said. “When that happens, that's very stressful for the pawpaw, and then they emit ethyl alcohol, which is an attractant to these new invasive beetles.”
The beetles have devastated pawpaw trees on his farmstead, throughout his neighborhood, and in orchards in neighboring states like Kentucky and Michigan.
Cory Christopher, the director of conservation for the Cincinnati Nature Center, says the invasive beetle hasn’t been impacting wild pawpaw trees in the southwestern Ohio nature preserve, but the insect is on his radar.
Invasive beetles often get introduced accidentally, he said, but they can cause serious damage.
Now, Chris Chmiel is figuring out how to move forward.
As Chmiel begins to replant, he’s experimenting with several strategies aimed at stopping the invasive burrowing beetles: a new drainage system, sandier soil and ethyl alcohol traps.
“We've definitely had to adapt,” he said.
But he’s hopeful they’ll find a solution, so people in Ohio can continue enjoying creamy pawpaws, just like they have for centuries.
