Across the Mid-Atlantic, giant oak trees are dying | Ap

TAKOMA PARK, Md. (AP) – Jason and Aga Jones love the beautiful oak tree that used to be the center of their yard. In 2013 – a year after they bought their home in Takoma Park, Md. – they returned a circular stone that remained around the base of the tree. In 2019, they added an extension to the back of the house with large windows where they could admire the majestic branches and watch the squirrels build nests and collect acorns.

Then in late summer, when they hired a company to cut the branches that blocked the neighbor’s yard, the company workers pointed out the unpleasant symptoms: browning leaves, dead sanga. Within a year, the tree was dead.

“It’s sad. We bought the house because of this oak tree. It’s a beautiful old tree, ”Jason Jones said, shaking as he looked at the brown leaves clinging to the lifeless branches last night before workers came to cut it down.

He took a tape measure from his basement to look at the tree: 12 feet in circumference, 4 feet in diameter. “Some arborist told me it was probably one of the oldest trees in the state, but unfortunately it had blight and it had to fall,” he said, looking at the wide green canopy of his neighborhood, then back. to himself. loud oak.

Oak trees are dying throughout the Mid-Atlantic region, crippled by extreme weather, old age, construction and development, then finally succumbing to disease and pests. Experts say the oak decline was triggered by a year of record rainfall that fell in the Washington region from 2018 to 2019, immediately followed by a flash drought in the hot, dry summer of 2019.

“The anaerobic conditions of flooded soil are not good for oaks,” said Karen Rane, director of the Plant Diagnostic Laboratory at the University of Maryland, noting that many of the hard-hit oaks are next to the construction of highway, where there are changes in drainage and soil compaction.

“They are losing oxygen to the soil. That’s stress on older trees – or on any tree, but older trees can’t tolerate it in the way younger trees can. That may have triggered an acceleration of decline in older trees, ”Rane said.“ When trees weaken, the trees emit signals that allow opportunistic insects to find them and attack. That was the last straw that broke on the camel’s back. ”

The oak decline has affected the DC region and states including Pennsylvania, Virginia, Maryland, Delaware, West Virginia and New Jersey, experts said. Symptoms are early browning of leaves, thinning of the canopy cover and loss of branches, wrote Dorothy Borowy, an ecologist and coordinator of integrated pest management for the National Park Service’s DC region, in an article last week. years.

Anne Arundel County in Maryland has even set up a web page where residents can report sick or dying trees.

The result of tree loss is most evident in communities with older trees, such as Takoma Park, where residents are concerned because the roar of chain saws and mulching machines illustrates the loss of one. more large shade trees.

Takoma Park, a DC suburb known as a liberal enclave, has strict provisions to protect its trees. A permit is required for the removal of any tree, alive or dead, with a trunk more than two feet in circumference, and for any erection, digging or pruning that will remove more than 10 percent. of “live canopy.”

Marty Frye, the city’s forest manager, said that in the years he worked for Takoma Park, more than half of the tree removal permits he reviewed were for oak trees. He started his current job in October 2020 but began working on tree removal permits in the city about three years ago-which, he told colleagues and property owners, began. increasing oak mortality.

Rane, who traveled throughout the region to observe the oak tree situation, said of Takoma Park, “It just so happens that there are a lot of trees in that town.”

His U-Md. colleague Dave Clement, a plant pathologist who joined him for a video interview with The Washington Post, estimated that most dying trees in the region are between 80 and 120 years old.

Rane added: “People think oaks live up to 300 years, but not in an urban environment. Too much is happening.”

At Jones ’home, Jason Jones picked up pieces of bark that had fallen from the tree to reveal small piles of sawdust under the tree. These piles, Frye says, are a “predictable sign” of pests such as the Ambrosia beetle, which attack after the tree indicates its weakness.

Some trees are slowly dying, losing branches over many years, Frye says. But others, like the head of the Jones family, died suddenly.

“That’s a more confusing, surprising sight,” Frye said. “It looks like it came out a lot, then browned out a bit early. This is consistent with placing the Ambrosia beetle’s claw on the coffin. “

The first symptoms of a diseased tree are mild: a thinner canopy, diminished leaf size and new branches about half the usual length, Clement says. “People don’t notice the size of the leaves, how thin the canopy looks, if you can see light through the canopy – those are subtle indications that things are on a less normal path.”

The symptoms then shift to sawdust from the beetles attacking the trunk, he said. “You start to see these organisms, and people ask, ‘What can I do?’ Well, it’s too late for remedial action. ”

Dying oaks suffer a lot of blows – and conditions caused by humans can exacerbate the problem, experts say.

In the video interview, when Rane and Clement saw a picture of the retaining wall around the base of the tree, they both exhaled. “That retaining wall around the tree wouldn’t have helped if it had risen in the last 10 years,” Clement said. “If that tree was a 25 -year -old tree, it probably didn’t suffer or had such an impact. But an older tree, if you start doing things around that, any root disturbance, they’re more sensitive. They are harder to recover. ”

“Some of the trees in this yard are dying from TLC,” Rane added.

Aga Jones said a thin stack of bricks surrounded the tree when they bought the house. The Joneses fortified it and built it shortly after moving.

Experts say that retaining walls, building near trees or even piling soil can take away oxygen from the roots, and the larger the wall, the worse it is for the tree. The builders did warn the Joneses that they could not build the wall too high because it would stress the tree, Jason Jones said, adding, “That was something we thought about when we built the wall, but we thought that it is a calculated risk. ”

In Oct. 20, the Jones couple cut large branches but kept the bulk of the tree, assuming they would build a treehouse for their children. But the dead trunk is too sad a sight – a reminder of the lost to them. They will first leave it for now for the woodpeckers ’feast but plan to cut it into smaller stumps in the spring, Aga Jones said.

Homeowners across the region are seeking answers from experts about how to rescue their trees. Clement said remedial ground work could help recover diseased trees – easing soil contact with an air spade or breaking down surface layers of the soil. He advised people to keep objects away from trunks – retaining walls, other plants or more soil – and avoid running the lawn mower over the roots. Mulching can help, Rane said, but he added, “If we continue to get extreme weather events … we will continue to see these events.”

Most important, Clement says, is a tree replacement strategy-a 25-to-30-year cycle of adding, removing and replacing trees.

“When a big tree falls, plant with another big tree – not with a short -lived tree” like a crepe myrtle, dogwood or redbud, Clement says. “I encourage people to continue to plant shade trees. Stagger their planting, space out the plantings. If you have a small yard, only one big tree really has space. “

The Joneses plan to plant another tree behind the area where the oak is located. Jason Jones worries that rotting oak roots could cause his yard to rot and become uneven. Clement said that shouldn’t be a concern and suggested looking at the bright side: “He might see mushrooms appear. He’ll have an increase of microorganisms in the insect soil, all sorts of good things happening.”

Right now, the death of their oak tree means less yard work: Jason Jones says he has to research half a dozen times each fall and clean up “tons of acorns.” But he already misses the squirrels eating nuts and nesting in trees: “It used to be Grand Central for them.”

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