MISSOULA — While it may have taken days for residents to get power restored or weeks to clean up their yards after the devastating storm that swept through Missoula last month, the city’s forest will take decades to recover.

The July 24 storm, which brought wind gusts of 80 to 100 miles per hour, damaged thousands of the city’s trees, according to the city’s Forestry Department. More than 600 trees were downed or slated for felling.

The storm exacerbates problems facing Missoula’s urban forest due to climate change, aging trees and inadequate maintenance, the Montana Free Press reports.

“It’s just overwhelming,” said Ben Carson, the city’s urban forestry program manager, during a news conference Thursday. “The program was already in a situation where we were struggling to provide services at the level we would like, and this situation comes along and blows that potential level of service. This is something we may be dealing with exclusively for an entire fiscal year.”

Five weeks after the storm, the city’s forestry department is still triaging, clearing debris, removing hazards and collecting data on the damage, said Morgan Valliant, deputy director of the city’s ecosystem services department.
“We won’t know the full extent of tree loss for several months,” he said. “While we’ve been recording and tracking it, we haven’t had a chance to count the number of trees that fell in this first event. We’re really focused now on mitigating and removing these hazards from our public spaces.”

While some types of trees are more likely to fall in normal storms, the July storm was “so severe that anything could fall,” said Marie DuCharme, an urban forestry specialist. Location played a role, as trees in open areas, such as near intersections, suffered more damage, she said. Downtown was not hit as hard as some other neighborhoods because taller buildings helped protect the trees, DuCharme said.

The city has identified nearly 460 trees that need to be removed, in addition to the 146 trees already cut down, DuCharme said. That number does not include trees on private property and will rise as staff continue to assess the damage, she said.

Carson said staff and volunteers have identified about 1,500 treetop hazards, including broken or drooping branches, and that number is expected to rise to 3,500 to 5,000 once the citywide inventory is completed.

The city will hire local or regional arborists to help manage the large number of damaged or fallen trees, Valliant said.

Residents and road workers have dumped an estimated 60,000 to 90,000 cubic yards of waste material at city collection sites, DuCharme said. That’s enough to fill Washington Grizzly Stadium to the last row of seats, she said.

In the next few weeks, contractors will bring in large crushers to process the rubble.

“I would say we’ll easily be busy for a year or a year and a half with the cleanup and tree issues after this event,” Valliant said.

DuCharme said staff will prioritize hazards and damage, document snags and note whether the site is a candidate for a replacement tree. She said corner trees generally aren’t replaced because they block motorists’ views.

Replanting lost trees will likely take years, DuCharme said.

The Urban Forestry Department will work with partner organizations to plan reforestation, looking for more resilient tree species, DuCharme said.

Many of the trees in Missoula, especially the older ones, are not native to the area and cannot tolerate heat, drought or storms, Susan Teitelman, climate resilience specialist with Climate Smart Missoula, told the Montana Free Press. Some trees fell over or were damaged because they were not planted deep enough or did not get enough water, she said.

According to the city’s 2015 Urban Forest Master Management Plan, Missoula’s aridity and lack of soil foundation make it not the best habitat for many trees. When Glacial Lake Missoula filled the valley, periodic drainage removed much of the topsoil, leaving a flat valley floor with a thin layer of soil over a bed of gravel, the report said.

According to the report, there were few trees in the Missoula Valley before settlement in the late 19th century. In 1874, Francis Worden – one of Missoula’s founders – imported fruit trees and Norway maples to plant around his house on East Pine Street. The maples were later planted throughout the city, especially in the Northside, Westside, University and Rose Park neighborhoods.

In 2014, 30% of the city’s 24,400 street trees were Norway maples and were nearing the end of their lifespan, according to the city’s Urban Forestry Master Plan released in 2015.

Carson, the urban forestry program director, said the majority of the 100 or so trees scheduled for felling before the July storm are still standing because they had little or no foliage and did not handle the wind as well as healthy trees. Rising summer temperatures, lack of water or root space, old age and early or late frosts in the fall and spring have damaged these trees, he said.

“These things really put additional stress on trees that are already nearing the end of their life in an urban environment,” Carson said. “We’ve seen an accelerated mortality rate … that I’ve never seen in my 15 years as an arborist in Missoula.”

The city’s Forestry Department, which includes Carson, DuCharme and three arborists, doesn’t have enough staff to maintain the city’s roughly 40,000 trees, Valliant said. Storm damage has exacerbated the department’s struggle to keep up with annual tree replacement and maintenance, Carson said.

The city’s forestry department is looking for volunteers to help with tree damage inventory. Those interested can sign up online, DuCharme said. Residents can report hazards by phone or online and are asked to be patient as staff respond based on risk, Carson said.

People with damaged trees that they do not know how to deal with are advised to contact a professional arborist, who are listed on the city’s website.

Teitelman said property owners who want to plant new trees should wait until fall or spring when the weather is cooler and wetter. She said trees, especially younger trees, need to be watered in the summer.

Those who are new to planting should be careful to plant the right trees in the right places and in the right way, Teitelman said. Trees for Missoula compiles a list of recommended climate-resilient trees and offers planting guidelines on its website.

“Our urban tree population is not doing well, so we want to make sure we plant more trees and also have a plan for how we care for them,” Teitelman said.

The good thing about the storm is that new plantings can now be planned if the community’s attention is on the trees, Teitelman said.

“For better or worse, people are thinking about trees now,” she said. “Maybe people have more negative opinions, but also positive ones. Everything else will just be a matter of continuing to educate and educate people about trees, about the importance of the urban forest and more technical things, how to plant it well and make sure it’s preserved for years to come.”