“I’ll interpret the rocks, learn the language of flood, storm, and the avalanche. I’ll acquaint myself with the glaciers and wild gardens, and get as near the heart of the world as I can.” -John Muir
Maintaining and reconstructing healthy natural ecosystems presents many challenges in a state like Iowa with our large-scale alteration and fragmentation of habitats. I have had the pleasure of walking our timbers, prairies, and waterways with a few experts on those subjects and I am always struck by the way they can read the landscape like a book, gleaning a story spanning hundreds or thousands of years where most may see only a static picture of what a parcel looks like right in this moment.
Cruising the timber at Bloody Run county park this winter, DNR forester Dave Asche pointed to the bifurcated stems of Oak trees. I had never given much thought to the abundant “school marms” gracing the blufftops along the beautiful trout stream, but Dave saw in them a story. The good, healthy Oak trees had been logged, perhaps a hundred years ago or more and resprouted from the cut stumps to produce two equal-sized stems.
Surveying the banks of the Volga River last fall with Dan Kirby and Mark Winn from the DNR’s Manchester Fish Hatchery, they point out the layer of lighter colored silt sitting atop the darker soil in a cut bank. The boundary between them speaks to the historic water levels of the Volga, which has since become more deeply incised as changes in land use on the watershed have disconnected the river from its floodplain.
The more a person learns about the dynamics of their ecosystem, the more that ecosystem comes to life, to tell a story replete with tension, rising action, and character development.
Learning to hear that story plays an essential role in the art and science of landscape restoration. Recognizing indicators of the historic composition of an ecosystem can help direct management activities to where they may help the most.
Oak savannas offer a prime opportunity. Once quite widespread in our neck of the woods, Oak savannas began to disappear when wildfire suppression became commonplace in the 19th century. While maple seedlings do pretty poorly when exposed to a burn, oaks survive and even promote fire with their curly, dry leaf litter. The partnership between oaks and fire stems from oaks’ need for full sunlight to thrive. Maple on the other hand does just fine in the shade and, with a long enough break between fires, will come to dominate a timber stand.
Fast forward to today, and many oak savannas are overgrown with maples that shade out oak seedlings. But how do we recognize these “degraded” savannas?
The oaks themselves tell part of the story. An open-grown oak has a wide, spreading crown with large branches closer to the ground than their timber-grown counterparts with long, branchless trunks. On a degraded savanna, you may see a massive oak tree with dead, naked branches on the bottom portion – “shade pruning” – surrounded by much smaller seedlings of shade-tolerant trees like maple and butternut hickory.
vBelow the tree, the herbaceous layer tells more of the story. “Indicator species” is a broad term in ecology for plants, animals, or fungi that thrive best in a specific habitat. Visitors to the Grau Memorial Savanna at Motor Mill find an understory rife with savanna indicators. Prairie plants like Big Bluestem or Goldenrod do not typically occur in a mature, shaded woodland, but abound on the Grau Savanna.
Of course not all savannas are created equal. Like prairies, savannas can either be “remnant,” or “reconstructed.” Reconstructed savannas are basically created from scratch, with the undesirable trees cut away and the understory planted with an appropriate mosaic of forbs and grasses.
Remnant savannas are those who have held on, through all these years, to their deep history. Recognizing remnant savannas takes a keener eye for those species who do not transplant easily, and thus most likely have existed on the site naturally for scores or hundreds of years.
Again we can look to the Grau Savanna, or even the more recent restorations at Bloody Run. Both sites host Hoary Puccoon, a handsome yellow flower notoriously difficult to germinate from seed. The presence of Puccoon indicates a site history relatively free of destructive disturbance. Fire and grazing are pretty major disturbances, but plants like Hoary Puccoon can often resprout following those activities due to their evolutionary history in landscapes rife with wildfire and bison. But should a site be plowed or row cropped, it’s unlikely to host Hoary Puccoon.
This gets at the concept of a plant’s “coefficient of conservatism,” or CoC. CoC, broadly speaking, assigns a number from 0-10 to a plant’s likelihood to represent a high-quality natural area. 0 would mean “this plant doesn’t tell me much,” like Box Elder which can pop up right in the middle of a crop field left fallow for a year or two. 10 would mean “this ecosystem is very similar to what it was 200 years ago,” like Witch Hazel on the steep slopes at Bixby State Preserve.
Hoary Puccoon has a CoC of 7 in Iowa, which is a pretty strong indicator that the savannas at Motor Mill and Bloody Run have been savannas for a long, long time.
Spotting these indicator species, and especially those that indicate “remnant” ecosystems can really help landowners and managers figure out where to target their efforts. While reconstructing our disappearing ecosystems is certainly an admirable goal, the priority should be maintaining the good habitats we still have.
More importantly, learning the language of the landscape brings a new sense of dynamism to a walk in the woods. The towering white trunks of Aspen trees represent a forest still in its infancy. The graceful purple blossoms of lead plant represent an ancient prairie. If we can learn to hear these stories, we can better find our place within them and ensure that they will echo for generations.
June saw the tentative resumption of some public programs, including the Stewards of a Beautiful Land program co-hosted by Clayton County Conservation and Trees Forever. Participants enjoyed a walkabout at the prairie reconstruction above the Osborne Pond, agog at the display of wildflowers put on in a planting not quite two years old.
We also had the pleasure of planting some 500 wet-loving species along the banks of the Osborne pond in between storms, thanks to a Watershed Guardians grant courtesy of Northeast Iowa RC&D, Alliant Energy, and the EPA. With a little luck, these plants will make the already-lovely fishing pond a little more resplendent in midsummer!
On the outreach front, naturalist Abbey Harkrader and naturalist intern Natalie Palmershein have continued to do fantastic work in making nature go digital. If you haven’t yet checked out their videos on animal enrichment and wild berries, you’re missing out!
July 11th is a big date! Motor Mill tours will resume that day, and with a little more cooperation from the river Pedal, Paddle, Purchase will take place wherein participants ride from Elkader to Frieden Park before paddling back home and enjoying a little shopping/snacking around town.