A rise in human deaths could be correlated to an invasive species called the emerald ash borer that is killing trees across the Midwest, according to a recent study.
The larvae of the emerald ash borer, a beetle native to Asia, feed on the inner bark of the ash trees, crippling trees’ ability to transport water and nutrients. As of 2012, it had killed more than 100 million trees in the U.S.
The study from the Pacific Northwest Research Station studied tree loss from 1990 to 2007 across 15 states. It found the ash borer was associated with an additional 6,113 deaths related to illness of the lower respiratory system, and 15,080 cardiovascular-related deaths.
“If trees are good for you, then killing a lot of them at a short amount of time should be measurably bad for you. That is what it comes down to,” says research forester Geoffrey Donovan, who led the study.
The study warns there are 7.5 billion ash trees in the country and the ash borer is a threat to all 22 species.
Cities and states have been trying to eradicate the ash borer, but with little success. One of the methods they have used is cutting down trees that have been too devastated to survive. That could help stop the beetle from spreading, but also destroys the tree.
Fort Wayne has one of the biggest ash tree populations in Indiana. The city’s Superintendent of Urban Forestry Chad Tinkel says they have been fighting the bugs since 2004.
“We started in 2008 with 14,000 ash trees just on the streets alone,” Tinkel says. “Since then we are down, I would say we have, after this year we will have cut 11,000 trees on the streets.”
Tinkel says the city does not have the funds to replace the trees right away, but he says they plan to plant new trees within 10 years.
View the state’s interactive map of where ash borers have been identified in Indiana.