A new report by the Iowa Department of Natural Resources shows a decline in the tree species that have been considered the center posts of the state’s forests. D.N.R. forester Aron Flickinger, says the trend that is raising concern was discovered after an analysis of the U.S. Forest Service’s annual inventory.

Flickinger says the inventory showed the oak-hickory forest type has declined from 37% percent in 1990 to 26%percent in 2008. “That just seemed like a pretty big decrease, that’s almost a third of our oak-hickory forest type,” Flickinger explains. Flickinger says other types of species are filling in the forests.

Flickinger says trees that regenerate in the shade — such as mulberries, locust, cherry, bitternut hickory and sugar maple — are increasing in numbers. While the trees that don’t reproduce well in the shade aren’t increasing. Flickinger says the natural impacts that shaped the forests have changed. He says storms used to open up a lot of light into the forests, and there used to be fires that raced through the forests and burned off the shade tolerant species.

The oak-hickories would survive the fires and regenerate, so that’s why they became the dominant species. While Iowa is more well known for its fields of corn and beans than its forests, Flickinger says there are three million acres are forests that contribute to the state economy.

Flickinger says the oak-hickory trees provide a lot of the wood products for the $4-billion lumber industry in Iowa. He says the wood industry employs 18,000 Iowans. And he says many species of animals, such as turkeys and deer, depend on the acorns for food. Flickinger says they’ve found there are about 132 species that depend on Iowa’s forests.

Flickinger says the report shows the need for Iowans to manager their forest lands just as they would any other crop in the state. He says there are several different options land owners have. If they have a mature oak-hickory forest, they can do things to manage it well, but if it is already have a lot of the shade tolerant species, then it becomes more difficult to get rid of them.

Flickinger says local foresters can help landowners manage their oak-hickory forests to keep them vibrant. You can see the entire “Iowa Forests Today” report on the Iowa D. N.R. website : www.iowadnr.gov/forestry/assessment.html