Study shows benefits of public trees

Trees can provide shade on a warm summer day and block the wind on a cold winter day. Each public tree in Whitefish provides almost $100 annually in quantifiable benefits, according to a recent community forest report by the Montana Department of Natural Resources and Conservation.

City street and park trees play a vital role in communities providing aesthetics, economic and environmental benefits, the report notes.

There were about 3,500 public trees in Whitefish when the survey was completed that resulted in the DNRC report that examines urban forests statewide. Whitefish’s trees provide more than $340,000 total in annual benefits — air quality improvements, energy savings, stormwater runoff reduction, atmospheric carbon dioxide reduction and aesthetic contributions to the social and economic health of the community.

Three more trees were added to Whitefish’s urban forest Friday when the city of Whitefish with help from second-graders from Muldown Elementary planted bur oak trees in Memorial Park in celebration of Arbor Day. Those new trees are estimated to each provide $8 in yearly benefits now and that figure will increase as they grow.

Dan Cassidy, who is operations manager for the DNRC Northwest Land Office and serves on the city’s tree advisory committee, said the report show the value and community benefit of trees while examining species diversity and looking at the threat of insects and disease.

“Intuitively people like trees,” he said. “They provide shade and do increase your property value. By putting a dollar value on the trees that might make people pay more attention to the trees. If you save a tree, there’s a benefit.”

The DNRC report, State of Community Trees in Montana, analyzes data on tree species, size, age, location, condition and other factors in 61 communities around the state. To better understand the state’s community forests, DNRC compiled public tree inventory information of 138,420 trees located in street rights-of-way and city parks statewide.

The city of Whitefish participated in the DNRC study inventorying all trees in 2014 and then city Parks Department received an Urban Forestry Grant from DNRC that allowed it in 2017 to gather data to update the inventory.

THE TOTAL replacement value for all of Whitefish’s public trees is $3.5 million, according to the fact sheet included in the DNRC report that breaks down information specific to each community’s urban forest. There are 85 unique species in Whitefish with the top five most common species being Norway maple, green ash, littleleaf linden, red maple and quaking aspen.

Benefits of Whitefish’s trees include 1.4 million gallons of stormwater runoff reduced annually, 246 pounds of air pollutants removed annually, $32,274 in energy savings and 38,278 pounds of carbon dioxide sequestered annually.

Whitefish’s community forest, like the state as a whole, has a higher than recommended percentage of Norway Maple at 15.9 percent and green ash at 11.9 percent. Best forestry practices suggest that no single species represent greater than 10 percent of the total population.

Jen Sybrant, landscape foreman for the city, said the information provided from the tree inventory and the DNRC report will help Whitefish better plan its approach to the urban forest moving forward.

“The inventory and update gave us a value for every tree and a health rating for every tree,” she said. “The inventory told us that for green ash and maple we are overpopulated and that will direct us to not plant those in the future. We are looking more toward drought-resistant, hardy trees that do well in a cold climate.”

The Parks Department in planting new trees plans to use the 10-20-30 rule, which recommends no more than 10 percent of any one species, 20 percent of one genius and 30 percent of any one family.

The study says 52.1 percent of Whitefish’s trees are considered in good condition.

Philip Hodge, Whitefish’s landscape technician, said the survey resulted in health information about the city’s trees including that roughly 175 are in need of immediate attention. It also found that about 1,600 need some kind of maintenance.

“As we continue to add trees to the city we can add to that inventory,” he said. “The data will allow us to maintain all the tees in a more efficient way.”

The Parks department removes trees when they are dying or become a public safety concern and also plan to replace removed trees when funding is available. In the city parks the plan for 2018 is to plant 20 trees.

The department has a 10-year goal to provide more community education and involvement regarding trees, Sybrant and Hodge note. They would eventually like to see a tree program that would train volunteers to assist city staff with maintenance of the city’s trees.

“We both love trees and we both do the best we can,” Sybrant said.

“The more people know, the more they can help us,” Hodge adds.

The city currently has an adopt-a-tree program that allows homeowners to apply for trees to be planted in the boulevard in front of their home if they agree to provide proper irrigation for the first three years of tree’s life.

AS PART of the DNRC study, public trees were inventoried across Montana between 2008 and 2015.

More than 180 unique tree species were identified across the state and the predominant trees statewide — representing 42 percent of the overall population — were various ash species followed by Norway Maple and crabapple.

The state’s trees are estimated to provide $17.2 million in total benefits and the replacement value of the trees is listed at $185 million. The report notes that 55 percent of the trees in the state are in good condition. Statewide the age distribution of all trees was quite favorable, the report notes, with nearly half of the trees as young trees, which ensures a future forest to provide benefits for many years.

However, the state’s urban forests aren’t without problems.

The types of trees could benefit from more diversity.

Ash are the most commonly planted trees in several Montana communities, especially east of the Continental Divide. Nearly 30 percent of trees inventoried were ash. The dominance of any single species can have detrimental consequences in the event of storms, climate change drought, disease, pests or other stressors, the report notes.

The Norway Maple population also exceeds the recommendation.

Pests like the emerald ash borer, which has killed millions of trees in at least 30 states since 2002, threatens to drastically change communities with an over-abundance of ash, according to DNRC. The beetle is not known to be in Montana yet.

The goal of the inventory, according to DNRC, is to increase public awareness of urban forestry issues while promoting tree planting in appropriate places with a diverse range of species and producing a statewide urban forest management strategy.

To view the full report on the state’s trees, visit http://dnrc.mt.gov/divisions/forestry/forestry-assistance/urban-and-community-forestry/statewide-urban-forest-inventory.