Researchers Reveal Original Landscape Along Cedar and Iowa River Basin

Des Moines, Iowa—October 24, 2006—Until recently, the areas in the Iowa and Cedar River Valleys’ were considered to be deep forests right to the river’s edge. However, descriptions from surveyor notes and historical records suggest this area in the late 1830s was actually open parklands with scattered trees and vast expanses of prairie grasses underneath, called lowland savannas.

This is notable because savannas are considered to be one of the rarest native ecosystems in the region. The Cedar and Iowa River Valleys extend across east-central Iowa to the Mississippi River.

“This new research indicates that we need to rethink the way we manage our floodplain forests if we want to maintain healthy woodland communities in Iowa,” stated Dave De Geus, director of conservation programs for the Nature Conservancy.

A recent study commissioned by the Conservancy through a Roy J. Carver Trust details the land at the time of Euro-American settlement, from 1830 to 1845. The data obtained from the study will be influential to the Conservancy during the restoration process of these once widespread habitats.

Connie Dettman, graduate research assistant at Iowa State University gathered and assessed historical maps and documents and surveyor notes to glean the descriptions of the landscape before any major alteration took place. From there, she suggests a basis for future land management in the area.

“It is likely that wildland fires and flooding together maintained the historically open woodlands,” said Dettman. “However, by suppressing fires and changing water flow, we have allowed for the growth of closed canopy forests with different composition than the historical woodlands. Therefore, land managers need to use fire and run-off control techniques to restore these native processes.”

Currently, the Conservancy conducts prescribed fires to restore oak woodlands on its preserves along the Cedar River near Conesville. These fires, also called controlled burns, reenact the natural process of these wildfires and eliminate the potential for a more catastrophic fire. Fire is one land management technique that will help recreate the landscape from the 1830s. Furthermore, local landowners will have access to the study data and assistance to make plans to return their private woodlands to the natural condition.

“We are finding that many rare turtles and snakes, like the Blandings turtle, Illinois mud turtle and the Massasagua rattlesnakes are disappearing from the Lower Cedar Valley as the woodland continues to increase in tree density. Foresters are also finding that oak regeneration is not occurring due to intense shading,” said De Geus.

This research will aide in accurate restoration of the deep forests present in the Cedar and Iowa River Basin today to the lowland savanna of pre-Euro-American settlement. Eventually, the fragile savanna ecosystem will provide and ideal home to many unique animal and plant life.

The Nature Conservancy is a leading international, nonprofit organization that preserves plants, animals and natural communities representing the diversity of life on Earth by protecting the lands and waters they need to survive. To date, the Conservancy and its more than one million members have been responsible for the protection of more than 15 million acres in the United States and have helped preserve more than 100 million acres in Latin America, the Caribbean, Asia and the Pacific.

The Nature Conservancy in Iowa has more than 7,500 members and manages 33 preserves totaling over 6,000 acres. Since the Chapter began in 1963, with the aid of volunteers it has been involved in the protection of nearly 20,000 acres in the state, including native prairies, wetlands and woodland communities.