If you see pine trees turning orange and yellow this season in New Hampshire, don’t be too alarmed. They’re probably not dying, according to Kyle Lombard, a forest health specialist with the New Hampshire Division of Forests and Lands.
But they are experiencing a particularly epic case of white pine needle damage, particularly in the western and central parts of the state.
“This year, oh boy, my phone's melting off the wall,” Lombard said, with dozens of callers asking about the sad-looking trees.
The disease comes from a group of fungi that are native to New Hampshire, but only started attacking pine forests in the region about 15 years ago.
“They've been around forever. But for some reason, a decade or so ago, they seemed to start working together and causing us issues,” he said. “All of a sudden the trees would turn orange in late May, early June.”
The fungi infect a tree’s needles during the spring, as they’re starting to emerge. But it only ends up killing the needles the following spring.
This year’s needle damage has been so bad, Lombard says, because last spring was so rainy.
“It's just like any other fungi. Humidity and temperature and timing are really important," he said. "Over the decades, we've started to have wetter and warmer springs and that really has favored fungi."
Lombard says his agency hasn’t studied the connections between white pine needle damage and climate change, but as the region gets warmer and wetter, the connections seem clear.
“How else do you explain why we've started having more needle diseases that rely on wet, warm weather?” he said.
Lombard’s team is starting their yearly project — recording data on all the state’s dead and dying trees from a tiny airplane — early this summer, to try and gather information on the needle damage.
Though trees aren’t likely to die from the needle damage, the disease can have big impacts, especially on older pines.
“It's just like anything else," Lombard said. "The older you get, the more little things start bothering them."
A 100-year-old pine that’s had its needles damaged every year is stressed out and more susceptible to other threats, like drought or bark beetles, he said.
Lombard says people should not cut down their pines if they turn orange. Their new needles will grow over the summer, and come August, the trees should be green again.