By Peter Ziegler, Project Director – habitat@wisducks.org
This article originally appeared in Wisconsin Waterfowl Association’s April, 2022 Newsletter edition.
Everyone likes the pictures of big machines moving dirt to restore wetlands. I like them too, and it is pretty rewarding when the engines start rumbling and the ground begins shaking, but that is not always the answer for successful restorations. I see a lot of wetlands in every condition imaginable when I cross the state doing project reviews. I give landowners the best advice I can offer, sometimes it’s “enjoy what you have, it’s already a a well intact ecosystem”, to “this has little benefit to wildlife, let’s see what we can do to improve on that.”
“Let’s see what we can do” can take on many more forms than I can explain in this article, because every wetlands is unique. If a 50,000 pound machine is not needed, what do we – or what can we – do? Most likely in these cases we’re talking about enhancement and maintenance. I’m going to be honest with you, in the state of Wisconsin we have so many degraded wetlands and they all need some intense or regular maintenance to enhance their benefit to wildlife. Ask yourself this, in Southern Wisconsin, how many wetlands do you see without any cattails? Odds are the cattails you see are the nonnative species that dominate and replace native vegetation and decrease the wildlife benefits for everything from small invertebrates to migratory waterfowl. By the way, those small invertebrates are hugely important to egg laying hens to be successful.
Enhancement and maintenance activities take on many forms depending on the goals and present condition of the property; water level manipulation, woody removal, prescribed fire, herbicide, mowing and more may all be advised. Water level manipulation is a key component when and where there is ability. Natural wetlands have varying water depths during the year and from year to year. So don’t keep your wetland the same depth all the time; mimic nature and dry it out periodically, keep it half full or raise it as high as possible if you’re trying to control cattails. Of course, you will have to plan ahead and draw your wetland down in October the previous fall, cut all the cattails low and wait for spring runoff to drown them. Prescribed burns/fire can be an economical and beneficial tool but is not conducive to all wetland ecosystems. Fire removes thatch, stimulates natives and suppresses nonnatives if timed correctly, but keep in mind this should been done by a professional to make sure all appropriate permits, training and environmental conditions are correct.
A combination of activities is many times the most effective to enhance and maintain a wetland. Herbicide application and burning will get you a leg ahead of the invasive species for quicker and better wildlife habitat. But it’s not always about killing. Similar to water level control, you can use nature to get rid of invasive species in some cases. Planting can play a key role. Tree and shrubs inhabit many types of wetlands. They can be used to transition a degraded Reed Canary Grass (RCG) wetland to a forest or shrub wetland, which will sustain a broader range of wildlife and higher diversity of species. You would be amazed at what will appear from the seed bank once the RCG is suppressed through the shade of the trees and shrubs.
The 50,000 pound machine is fun to see, but don’t forget that WWA provides all sorts of advice to landowners for management, enhancement and maintenance beyond heavy equipment. If we could bring 50% of the degraded wetlands in our state back to something of quality I believe we would see a huge increase in wetland dependent wildlife diversity. I’m sure if you have questions about your wetland; we can provide you with an answer.
Regrowth after a spring burn prior to inundation knocks back woody species, stimulates the native sedge community, suppresses the Reed Canary Grass and provides spring migratory bird habitat.