Published Aug 2, 2023

Purgatory Creek: A Tale of Oxbow Restoration on a Legacy Farm

By Vanya North

On July 12, Kathy and David Law led a field day with Practical Farmers of Iowa, showcasing their 300-acre corn, soybean and cattle farm in Lohrville, Iowa. Farming since the 1970’s, the Laws recently partnered with the U.S. Fish and Wildlife Service (USFWS) to restore a total of four oxbows on the farm to create vital aquatic habitat.

The Laws started working with Darrick Weissenfluh of the USFWS and Brandon Iddings of the Iowa Soybean Association (ISA) in 2021, with the restoration of the first oxbow beginning in December of that year. The oxbows on the Laws’ farm were the first to undergo restoration along Purgatory Creek, though more have since followed. Initial site surveys and assessments were conducted by the USFWS, and the project later co-opted with the ISA to oversee construction of the oxbows. Three of the four oxbows were restored in an active pasture. The fourth is a tile-fed oxbow located in a riparian corridor. The Laws signed a 10-year maintenance plan with USFWS and were able to combine several funding sources and paid nothing out of pocket for the restoration.

Darrick Weisshenfluh USFWS

Darrick Weissenfluh of the US Fish and Wildlife Service discusses the importance of oxbows and which agencies can assist farmers to install them on their own farms.

On the morning of their field day, Darrick and Brandon started the group off at the oxbows in the active pasture area. Attendees were serenaded by chorus frogs as Darrick and Brandon explained that the sediment from the restoration was excavated and then distributed in adjacent crop fields to further build up crucial soils in those areas and allow nothing from the reconstruction of the oxbows to be wasted. These crop fields produced 20 more bushels of corn after the excavated soil was added to them.

Pastural oxbow at David and Kathy Law farm

The pastural oxbow on David and Kathy Law’s Lohrville Farm is unusual, in that it is the convergence of two oxbows, creating a distinct diamond shape.

After viewing the pastural oxbow, attendees loaded up and headed out to an oxbow on the other side of the farm to a restored area along a riparian corridor. Brandon enthusiastically dove into the oxbow with a couple of fish traps. During the restoration, the endangered fish species known as Topeka Shiners, have been found in the restored riparian areas of the Laws’ farm. The Topeka Shiner has been found now not only in the Laws’ restored oxbow, but also the North Raccoon River, hopefully indicating progress in environmental restoration. During this field day, no Topeka Shiners were found, but a variety of minnows and green sunfish were observed.

Purgatory creek at Law farm

Topeka Shiners have been found in the restored riparian areas of the Laws farm. Purgatory Creek and the restored oxbow of the Law farm only connected for 24 hours while water levels were up, but it was enough to allow Topeka Shiners into the riparian oxbow.

A variety of other wildlife regularly visit the Laws’ farm as well. Darrick often places a wildlife camera overlooking the oxbow and has documented northern leopard frogs, great blue herons, wood and mallard ducks, bald eagles and pheasants. Deer, raccoons, and beavers also visit the restored habitat. While attendees of the field day didn’t glimpse any of this wildlife either, they did hear a variety of frogs. The day concluded with the wildlife viewing.

PFI would like to thank David and Kathy Law for hosting a great field day full of amazing wildlife and Darrick Weissenfluh of the US Fish and Wildlife Service and Brandon Iddings of the Iowa Soybean Association for all their hard work in restoring this and other oxbows across Purgatory Creek. You can find more information about restoring wetlands and oxbows with the US Fish and Wildlife Service on their website.  For more information about new cost-share programs with Practical Farmers of Iowa focused on conservation, visit the cost-share page on our website.

Minnows and sunfish found in Law farm oxbow

A variety of minnows and sunfish were observed in the Laws oxbow during their field day on July, 12th.