Sierra Club: DNR forest plan doesn’t address climate change

Iowa's Yellow River State Forest is in extreme northeast Iowa. (Photo courtesy of Iowa Department of Natural Resources)

Iowa’s new Forest Action Plan doesn’t thoroughly address one of the top threats to Iowa’s relatively small tracts of trees — climate change — an environmental group says. 

The Iowa Chapter of Sierra Club objected to the draft plan, which has to be updated every 10 years for Iowa to qualify for certain federal funds. The Iowa Department of Natural Resources’ comment period ended Dec. 25. 

Sierra Club wants to plan to help protect the state forests from damage from high-wind storms such as the August derecho, heavy rains expected to become more commonplace in the future, and other changes due to climate change. 

“The DNR needs to expand their report to look at reforesting in a response to the derecho and how Iowa’s forests are going to change as a result of climate change bearing down on our state,” said Pam Mackey-Taylor, director of the Iowa Sierra Club, part of a national nonprofit. 

DNR spokesman Alex Murphy did not immediately respond to an email seeking comment.

Research at Iowa State University and elsewhere has shown the Midwest could see more frequent severe weather such as tornadoes, drought, floods, changes in wind speeds, and warmer nights as climate change progresses.

Sierra Club said those changes and affect trees and should be more directly reflected in DNR’s report. 

Jess Mazour, Iowa Sierra Club’s conservation coordinator, said the health of Iowa’s forests affect the broader environment. “Thriving forests provide habitats for threatened and endangered species, capture carbon from the air, and slow down water from increasing rain events,” Mazour said. “Forests are more than crops for economic value. They benefit all Iowans and our environment.” 

DNR produced the latest forest plan with interactive software that allows viewers to examine various different threats to trees. 

The report also summarized some of the biggest challenges Iowa’s forests face: 

Gypsy moths: The pests like to eat oak leaves and cause $22 million a year in damage to property and wood products. 

— Emerald ash borer: The beetle that originated in Asia has cleared out urban trees more than anything since Dutch elm disease in the 1960s. Much of Iowa’s forest is populated by ash trees, and the borer is causing $27 million a year in damage to Iowa’s economy, DNR reported.

The U.S. Forest Service in 2019 reported Iowa had 52 million ash trees in woodlands, and 3.1 million in urban areas. Ash trees can be treated to withstand the borers but most cities are removing the trees to protect lives and property. The trees die within two years of infection with the beetles, which cut off the tree’s food source. DNR reports that once the beetles are found in the community, nearly all ash trees will be dead in five or six years. The borer has been confirmed in 76 Iowa counties

Bur oak blight: Bur oak is the state tree, and the wood is highly valued, along with Iowa’s walnuts, for lumber. The blight, caused by a fungus, has caused some oaks in 91 of Iowa’s 99 counties to lose their leaves. Of 32 million oak trees in those 91 counties, 8.7 million are bur oaks, the Iowa State Plant Insect and Disease Clinic reported in 2016. The blight is a $19 million hit on Iowa’s economy, DNR estimated.

— Thousand cankers disease: Caused by a beetle that carries a fungus, this disease has been killing black walnut trees in the western United States since the early 1990s, DNR reported. Should the disease spread in Iowa at some point, the state’s walnut-related economy would lose $43 million a year, the state estimates. Iowa has the equivalent of 979 million board feet of walnut, the third-largest stand in the world, DNR reported.

Asian longhorned beetle: A pest native to China, the beetle larvae like to tunnel through maple and birch trees. The beetle has not been found in Iowa. If it spread here, it could do $222 million in total damage to land values and wood products.

The full DNR report is available here