Nearly one-third of all trees in urban forests wrapped around the southwest shore of Lake Michigan are those species found to be most vulnerable to the adverse effects of climate change, says a new study by the U.S. Forest Service.

The health and numbers of at least 85 tree species evaluated in the study are expected to decline over the next several decades.

Urban forests in a region extending from southwestern Michigan through northwestern Indiana and northeastern Illinois to southeastern Wisconsin will need to adapt to a climate change forecast that includes rising temperatures and increasing precipitation, according to the study published this month, "Chicago Wilderness Region Urban Forest Vulnerability Assessment and Synthesis."

Woodlands in Milwaukee County's Grant Park or Waukesha County's Nashotah Park will not be lost entirely due to a changing climate but they will look different than today. Some of the natives, ironwood, shagbark hickory and bur oak are expected to do well.

But each pin cherry, white oak and paper birch missing from Wisconsin landscapes of the future could be replaced by trees that we now consider to be southern species.

Shumard oak, native to southern Illinois, likely will become more common north of its home base. Foresters in the Chicago metropolitan area are planting Kentucky coffeetree to see how well they do.

"Communities have invested in their urban forests and the information that we provide can be used to maintain healthy forests," said Leslie Brandt, a Forest Service climate change specialist at the Northern Institute of Applied Climate Science in St. Paul.

This study will enable municipal foresters and private landowners to plan ahead, said Brandt, the lead author of the study.

By maintaining a diversity of healthy trees, the urban forests will continue to provide valuable services such as removing pollutants from the air, providing shade and reducing energy costs, and taking up stormwater, she said.

PDF:Urban forest vulnerability assessment

"Sounds like we're going to lose some species of trees, and we could gain some species," said Ramsey Radakovich, deputy regional operations manager in the Milwaukee County Parks Department's land resources division.

The parks department is a step ahead of the game by its use of a 2015 state urban forestry grant to begin an inventory of trees in parks and parkways needed for a sustainability management plan, Radakovich said. That developing plan will keep an eye on climate change effects as well as more immediate threats to the local tree canopy, such as the emerald ash borer and its destruction of white ash.

The ongoing inventory shows that some of the most common trees in Milwaukee County parks — green ash, sugar and Norway maple — are among the most vulnerable to climate change. In response to the study, the county will adjust its selection of trees for planting, Radakovich said.

Trees native to northern areas — such as black cherry, white pine, paper birch, quaking aspen and balsam fir — are among the 15 species most susceptible to the adverse effects of increasing temperatures and more intense, erratic precipitation in a changing climate, according to the study published this week.

GRAPHIC:A changing forest

White ash, white oak, pin cherry and northern white cedar, known as arborvitae, are on the list of 16 tree species with a moderate to high susceptibility to climate changes, the study says.

The list of 54 tree species found to have a moderate vulnerability includes several natives, such as sugar maple, black walnut and eastern cottonwood. Commonly planted species include Norway maple, blue spruce, apple and crabapple species.

These three groups account for 32% of trees in the study area. The Wisconsin portion of the region encompasses all of Racine and Kenosha counties, and portions of Milwaukee, Waukesha, Walworth and Jefferson counties.

"In the past century, the Chicago region has warmed by about 1 degree Fahrenheit and has experienced a significant increase in precipitation, as much as 3 inches during the summer," the study says.

By the end of the century, climate modeling for the region projects that temperature and precipitation will be more erratic.

Urban forests will face: average annual temperature increases of between 2.3 degrees and 8.2 degrees; precipitation increases in winter and spring; increasing frequency and intensity of rain and snow storms; and increasing duration and frequency of extreme droughts.

Vulnerability to a changing climate varies by species, according to Brandt.

There will be some "direct mortality from tree diseases that become more prevalent because winters are warmer," she said.

"Some species will become more vulnerable to limbs breaking from high winds" during more frequent storms, Brandt said. "Some will be stressed by heat and drought, and then become vulnerable to insects and fungal diseases."

Don Behm can be reached at don.behm@jrn.com and twitter.com/conserve.