ORNL ecosystem ecologist Verity Salmon said most trees are able to withstand the light damage inflicted by cicadas. However, it’s possible that trees exposed to other risk factors — such as lightning strikes, drought or fire — or particularly old or young trees could be at an increased risk of suffering from cicada flagging.
“If you only have a few branches, and this sort of flagging represents your whole year’s carbon budget as a young tree, it could be a more severe blow,” Salmon said.
Cicadas are endemic to North America and possess a natural cadence with the trees, meaning it’s unlikely that their mating processes will inflict severe damage to forests.
“The forest as a whole is more complex than any one tree. The tree is a lot more than just the leaves that we pay attention to above ground,” Salmon said. “Trees have stored carbon reserves in sturdy trunks and below ground in roots that we often don’t really think about when we visualize a tree or a forest, so they’re really resilient.”
Despite the frequency of cicada flagging in areas such as East Tennessee, news about flagging is few and far between — perhaps because to many observers, the browning leaves easily blend into the rest of the vegetation.
“If you’re looking for it you notice it, or if you live somewhere and tend to think about the trees a lot, it’s pretty noticeable,” Salmon said.
As a researcher in the lab’s Environmental Sciences Division, Salmon finds herself surrounded by colleagues eager to answer questions and make observations about the natural world, from uncovering the mystery of the reservation’s browning leaves to grabbing binoculars for a better look at a hummingbird nest on campus.
“It’s a good workplace if your coworkers share your interests,” she said. “It blends that professional expertise and personal interests. ESD is a good place for that, and I like it a lot.”
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