Boise & Garden City

Tree torts in the City of Trees are rarely successful

As sawdust from a tree chipper fills the air, Brandon Biorn, urban arborist for Boise’s Community Forestry program, picks up freshly pruned elm tree branches near the bandshell at Julia Davis Park.
As sawdust from a tree chipper fills the air, Brandon Biorn, urban arborist for Boise’s Community Forestry program, picks up freshly pruned elm tree branches near the bandshell at Julia Davis Park.

In a way, it’s surprising how few people file tort claims against the city of Boise because tree branches fell on their cars or houses.

Over the 12 months between the beginning of last July and the end of June, the city received 18 tree-related tort claims. That puts trees among the most common causes for torts, but the number pales when you consider Boise has 40,000 to 50,000 trees in public rights-of-way.

Tort claims are legal notices that a plaintiff intends to sue a governing body. The city received more than 130 between July 2015 and June 2016. Besides tree issues, other common causes for these notices include sewer lines backing up into people’s basements, accidents involving police and other city-owned vehicles, as well as pedestrians tripping on sidewalks.

Boise rarely pays out on legal action stemming from branches that fall from trees. Since 2010, tree-related tort claims led to just four payments from the city totaling $6,260, risk specialist Jonny Bush said. That’s out of around 100 total tree-related claims during that time.

The last time Boise paid a property owner for a tree-related claim was after a limb fell on a property owner’s fence in November 2015. The damages totaled $260.

In most of those cases, Bush said, the city knew a tree had been damaged and had scheduled a repair or other response, such as removal, but didn’t get to it before a branch fell and caused some kind of property damage.


Boise’s complex lines of responsibility for trees give people a good excuse for assuming the city government is responsible for tree-caused damage.

Most tree-related torts over the past year concerned trees located in the strip of ground between a sidewalk and a curb. That strip is a public right-of-way. In Boise, it belongs to Ada County Highway District. So do the trees planted in it.

But the highway district doesn’t landscape the right-of-way strip or take any responsibility for the trees, spokeswoman Nicole Du Bois said in an email.

So what about the city? It has a Community Forestry program, after all.

“The city does have a limited budget where we do pruning in certain areas of the city every year on those trees, but it typically isn’t enough to really constitute full care of the trees,” city forester Brian Jorgenson said. “Now, we do our best. We tackle the trees that are the worst and try to address trees that have large, dead limbs or are bad structurally in some way.”

But Boise government also is not strictly responsible for tree maintenance.

Instead, the owner of the land next to the right-of-way bears that responsibility because of a city law titled “Boise Tree Ordinance.” The original law dates back to 1952 and has been updated a few times in the past 20 years. It states that private landowners are responsible for routine maintenance, including pruning and removal, of trees in public rights-of-way touching their properties.

That’s why it’s so rare for the city to accept responsibility for property damage caused by public trees.

Most homeowners insurance policies would cover the damages from trees or branches falling on homes or other structures, such as fences and outbuildings, said Dave Mulder, a consumer affairs officer for the Idaho Department of Insurance. Similarly, comprehensive car insurance typically would cover falling tree damage to the policy-holder’s vehicle.

However, most commercial policies don’t cover damage to other people’s property, such as cars or homes, Mulder said.


The City of Trees may have gotten its name from native cottonwood groves along the Boise River — a corruption of the French phrase meaning “wooded river” — but maples are the most common trees here now.

Silver maples in particular were a favorite of Boiseans in the early 1900s, Jorgenson said. The species has several benefits and some serious drawbacks. It grows fast and provides lots of shade. On the other hand, Jorgenson said, it’s brittle and prone to decay, and its shallow root system often damages sidewalks, curbs and other infrastructure.

Trees are living organisms, and they’re going to fail. ...We do our best to understand what causes them to fail and try to stay ahead of that game, but you put enough force on anything, it’s going to break.

Boise city forester Brian Jorgenson

The city no longer allows people to plant the silver maple in the right-of-way strips between curbs and sidewalks. But silver maples are still common, so mishaps and tort claims stemming from them are inevitable.

Other prohibited species include red maples, boxelders, poplars, willows and elms.

Sweetgum is another species whose limbs break frequently, Jorgenson said. Oaks are among the species of trees that resist breaking.

But Jorgenson stressed that poor maintenance practices can jeopardize any tree. That’s why the city requires landowners to obtain permits before pruning or removing trees in the public right-of-way and follow national pruning standards.

The city occasionally sends notices to property owners to tell them they need to address problems with their trees, Jorgenson said. Mostly, though, that’s a response to trees rooted on private land — not the public right-of-way — that overhang a public area, such as a street.


Pruning and other maintenance is a big responsibility for homeowners.

Jorgenson believes the payoff is worth the hassle.

“They get a very real benefit, not only just in having the beautiful presence of the tree and the tree that shades their yard and house and saves energy,” he said. “It also increases the property value, the resale of their home when it comes time to sell it.”

The public benefits, too, because trees make for a more pleasant city overall. This is one reason Community Forestry posts its intention to remove public trees for a month or so before cutting them down, Jorgenson said, unless the trees in question are in such bad shape that they pose an imminent danger.

“It’s a public asset, so we want the public to have the chance to — if they want to — argue the removal of the tree versus a pruning or something like that,” Jorgenson said.

Worried about a tree in the right-of-way?

The city of Boise’s Community Forestry program maintains a list of tree-services professionals that it licenses.

When a tree has to be removed, the city usually contracts with one of these providers, city forester Brian Jorgenson said.

“They all employ at least one person as a certified arborist,” Jorgenson said. “And we kind of hold those folks to pretty high expectations on their pruning practices, because we kind of are backing them up on the quality of their work. In that sense, they kind of represent the city.”

If you have a question about the health of a tree in the public right-of-way, you can call Community Forestry at 208-608-7700 to have an inspector come and look at it. Check for a list of tree service professionals the city licenses.

Who owns public trees?

Boise landowners are responsible for maintaining trees in public rights-of-way touching their properties, but the city pays when one has to be removed.

The cost of removal ranges from a few hundred dollars to a few thousand, city forester Brian Jorgenson said, depending on the size and location of each one and whether traffic has to be redirected to make room for the removal.

If the city hires a private contractor to remove the trees, that contractor keeps the wood, Jorgenson said. The city’s own Community Forestry program does a fair amount of tree cutting, too. Boise runs some of the woodthrough a chipper and then sells it as mulch for gardens and other applications. Sometimes, Community Forestry cuts trees into logs, which it sells as firewood for $80 a cord, Jorgenson said.

For more information, call Community Forestry at 208-608-7700 or check the program’s website at

Most common trees in Boise

1. Maples (including the Norway, silver and sugar maples)

2. Ash (mostly green and white)

3. Honeylocust

4. Elm

5. Linden

6. Oak

7. Flowering Pear

8. Sycamore and Planetree

9. Crabapple

10. Sweetgum

Source: Boise Community Forestry