MISSOULA — While it may have taken days for residents to get power restored or weeks to clean their yards after a disastrous thunderstorm rolled through Missoula last month, it will take decades for the city’s urban forest to recover.
The July 24 storm, which included wind gusts of 80 to 100 mph, damaged thousands of the city’s trees, with 600 and counting knocked down or slated for removal, according to the city’s urban forestry department.
The storm exacerbates challenges facing Missoula’s urban forest due to climate change, aging trees and insufficient maintenance, the Montana Free Press reports.
“It’s just an overwhelming thing,” said Ben Carson, the city’s urban forestry program manager, during a press conference Thursday. “The program already was in a position where we are struggling to provide services at a level we would like to, and this situation comes along and blows that potential level of service out of the water. This is something we’ll be dealing with exclusively for an entire fiscal year, potentially.”
Five weeks after the storm, the urban forestry department is still in triage mode, cleaning up debris, removing hazards and collecting data on the damage, said Morgan Valliant, associate director of the city’s ecosystem services division.
“We won’t really know the full extent of tree loss until months from now,” he said. “Although we’ve been recording it and keeping track, we haven’t had a chance to count the number of trees that came down in that initial event. We’re really focused now on just alleviating and getting those hazards out of our public spaces.”
While some tree species are more prone to falling during regular windstorms, the July storm was “so significant that everything had the potential for failure,” said Marie DuCharme, urban forestry program specialist. Location mattered, with trees in open areas, like near intersections, seeing more damage, she said. Downtown was not hit as hard as some neighborhoods because taller buildings helped protect trees, DuCharme said.
The city has identified nearly 460 trees that need removal, in addition to 146 already taken down, DuCharme said. That number doesn’t include trees on private property and will increase as staff continue taking stock of the damage, she said.
Carson said staff and volunteers have identified about 1,500 hazards in tree tops, including broken or hanging branches. Once the citywide inventory is complete, that number is expected to climb to 3,500 to 5,000.
The city will contract with local or regional arborists to help tackle the large number of damaged or downed trees, Valliant said.
Residents and road crews dumped an estimated 75,000 to 100,000 cubic yards of downed material at the city’s collection sites, DuCharme said. That’s enough to fill Washington Grizzly Stadium to the last row of seating, she said.
In the next few weeks, contractors will bring in large grinders to process the debris.
We’ll very much be cleaning up and dealing with tree issues from this event for, I would say, easily a year to 18 months,” Valliant said.
DuCharme said staff will prioritize hazards and damage, document stumps, and note if the site is eligible for a replacement tree. She said corner trees are generally not replaced because they block drivers’ line of sight.
Replanting lost trees will likely take years, DuCharme said.
The urban forestry department will work with partner organizations to plan reforestation, with a look at more resilient tree species, DuCharme said.
Many of Missoula’s trees, particularly the older ones, are not native to the area and are not tolerant to heat, drought or storms, Susan Teitelman, climate resiliency specialist with Climate Smart Missoula, told Montana Free Press. Some trees fell or were damaged because they were not planted deep enough or didn’t get enough water, she said.
Dry and lacking an adequate soil base, Missoula is not the best environment for many trees, according to the city’s 2015 Urban Forest Master Management Plan. When Glacial Lake Missoula filled the valley, periodical draining stripped away much of the topsoil, leaving a flat valley floor with a thin layer of soil covering a gravelly bed, the report said.
The Missoula Valley had few trees before settlement in the late 19th century, according to the report. In 1874, Francis Worden — one of Missoula’s founders — imported fruit trees and Norway maples to plant around his home on East Pine Street. The maples were later planted around the city, mostly in the Northside, Westside, University and Rose Park neighborhoods.
As of 2014, 30% of the city’s 24,400 street trees were Norway maples and near the end of their lifespan, according to the Urban Forestry Master Plan published in 2015.
Carson, the urban forestry program manager, said the majority of the approximately 100 trees slated for removal before the July storm are still standing because they had little or no foliage and didn’t catch the wind like healthy trees. Increasing summer temperatures, lack of water or rooting area, old age and early or late freezes in the fall and spring damaged those trees, he said.
“Those things really do put trees that are already nearing the end of their lifespan in an urban environment under additional stress,” Carson said. “We were seeing an accelerated rate of decline … that I haven’t seen in 15 years being an arborist in Missoula.”
The urban forestry department, which includes Carson, DuCharme and three arborists, does not have enough staff to maintain the city’s approximately 40,000 trees, Valliant said. Storm damage exacerbated the department’s struggle to keep up with annual tree replacement and maintenance, Carson said.
Urban forestry is looking for volunteers to help inventory tree damage; those interested can sign up online, DuCharme said. Residents can report hazards by phone or online and are asked to be patient, as staff are responding based on risk, Carson said.
People with damaged trees they don’t know how to manage are encouraged to reach out to a professional arborist, listed on the city’s website.
Teitelman said property owners planning to plant new trees should wait until fall or spring, when cooler and wetter weather is available. She said trees, especially younger trees, need to be watered in summer.
Those replanting should consider putting the right trees in the right places in the right way, Teitelman said. Trees for Missoula is compiling a list of recommended climate-resilient trees and has planting guidelines on its website.
“Our urban canopy isn’t doing great, so we want to make sure we get some more trees in the ground and also have a plan of how to maintain them,” Teitelman said.
The silver lining of the storm is the chance to plan replanting when the community’s attention is on trees, Teitelman said.
“For better or worse people are thinking about trees now,” she said. “Maybe people have more negative opinions but positive ones, too. Everything else is just going to be a matter of continued education and outreach about trees, the importance of the urban forest and more technical stuff, how to get it planted well, and make sure it is maintained for the next several years.”
