Post by Brett Peto
Good things start at seven in the morning. That’s when our group of four hiked 15 minutes off-trail into the heart of Middlefork Savanna in Lake Forest, part of the Lake County Forest Preserves in northern Illinois.
The air was warm, the sunshine spread everywhere. Spiderwort blooms were freshly open, a waist-high meadow of bluish-purple fireworks. We found the steel T-post marking the start of the day’s first transect and the red flag for the first plot.
Then we gathered our tools. A one-meter-square collapsible wooden quadrat, retractable tape measure, clipboard, data sheets, and each other’s knowledge of plants.
Well, my own knowledge, not so much. I was there to take photos and observe the three experts onsite: Pati Vitt, Manager of Ecological Restoration; Ken Klick, Restoration Ecologist II; and Pete Jackson, who authored a 2009 study on this preserve’s plant communities that served as his thesis for a master’s degree program. In my head, I called them the Plant Team.
Middlefork Savanna is home to a significant portion of remnant, or original, oak savanna, a plant community in between prairie and forest. Oak savannas are usually classified by having 10 to 50 percent tree canopy cover plus continuous plant cover on the ground. They’re also generally more biodiverse than prairies and woodlands. Different levels of light availability are crucial to maintaining this.
The definition is made a bit slippery by the fact that so little remnant oak savanna is left to study today. It’s thought that just 0.02 percent of what existed before European settlers arrived in the Midwest is still with us. Most of the oak savanna that remains is badly degraded due to human activity such as fire suppression, fragmentation, agriculture, animal grazing, and timber harvesting.
To restore these areas effectively, we need to better understand the few high-quality oak savannas left. Middlefork is one, serving as a regionally important reference site. But to be a reference site, we need to understand its plant populations.
Our Permanent Transect Vegetation Monitoring program can help. It tracks what plants are growing where so we can better protect native species. Transects are straight, fixed paths through a natural area, capturing various species within them. Permanent start and end points are marked with steel posts and GPS coordinates.
Every 10 meters along a transect, the vegetation monitor lays down a quadrat—that one-meter-square wooden tool mentioned earlier—to serve as the boundary of a plot. Then they identify and record the plants inside.
Our aim that day was to monitor four transects at Middlefork that Pete had last visited in 2005, and before him, Marlin Bowles, Plant Conservation Biologist at The Morton Arboretum, in 1996. The new data will provide insight on any significant changes in vegetation that have occurred over the past 14 years, for example, an increase in invasive species such as European buckthorn (Rhamnus cathartica) or reed canary grass (Phalaris arundinacea).
This allows our Natural Resources Department to gauge the effectiveness of our land management efforts over time. It’s a double-check on our strategies to preserve and improve native plant populations across Lake County, including controlled burns, native seeding, invasive plant control, deer population management, and hydrologic restoration.
Data collection that day was teamwork in the flesh. The process began with what are called cover classes. Each member of the Plant Team estimated the relative abundance of forbs, graminoids, and woody plants in a plot out of 100 percent. Woody plants, of course, produce wood as their structural tissue instead of green stems. A forb is an herbaceous, flowering plant without grass-like features; a graminoid is an herbaceous plant with grass-like features.
The percentages correspond with the alphabet: “A” for <15%, “B” for 15–30%, “C” for 31–50 %, all the way to “F” for >90%. On the count of three, Ken, Pati, and Pete would announce their estimate for each type. 18% for forbs—it’s “B,” then. 45% for graminoids—write down “C.” If numbers were pretty different, they reconsidered, discussed. Taking turns, the botanists recorded it all on specially designed data sheets atop a fluorescent orange clipboard.
Once the general cover classes were settled, identification of individual species was next. They were assigned their own cover class letters, too. Recitation of common names and scientific names filled the air beneath the tree canopy.
Prairie dock, mountain mint, New England aster, sawtooth sunflower, enchanter’s nightshade.
A, B, C, B, E—I’m glad my audio recorder was running.
Soon, the first plot was analyzed. One down, 49 to go.
Ken picked up the quadrat. Pete unwound the tape measure. We moved forward 10 meters, following the transect. Ken set the quadrat down and Pati readied the data sheet. The process started again: general to specific, high to low. Many names were familiar, but there were newcomers, too.
Tall coreopsis, fowl manna grass, marsh fleabane.
A few specimens had an identity crisis. If group discussion didn’t crack it, then it was time to use an identification key, or in verb form, key it out. Identification keys usually look like complex flowcharts. You start literally at square one, answering questions about a plant’s characteristics, narrowing the possibilities until you arrive at the true species.
In a pause between plots, Ken held up a small brown-black insect on the tip of his finger. “Here’s my namesake. It’s a click beetle!” he said.
“Put him on your shoulder,” said Pete, laughing.
Laughing too, Ken let it dart away.
Another pleasant discovery was purple milkweed (Asclepias purpurascens). Its bright purple-pink flowers glowed, nature’s neon. Like all milkweeds, purple milkweed is food for monarch caterpillars (Danaus plexippus). It’s also a nectar source for long-tongued bees, ruby-throated hummingbirds (Archilochus colubris), and other butterflies, including fritillaries and swallowtails. The plant is hard to miss.
One easy-to-miss plant was bastard toadflax (Comandra umbellata), which only grows up to a foot tall. Hemiparasitic, it pulls nutrients from other plants by latching its roots onto theirs. This limits the height of its neighbors, opening up sunlight. Bastard toadflax also produces dry, mealy fruits.
Perhaps the most interesting part to me was its name. How did this little plant get so memorable a moniker?
Toadflax is a common name for several plants in the Santalaceae family. Somewhere at some point, a botanist decided Comandra umbellata looked like a toadflax, but actually wasn’t one. So they attached bastard to the front, signifying false in this context.
The scientific name is a bit more descriptive. Comandra means “male hairs”—the plant has small hairs at the base of its stamens. Umbellata refers to its clusters of white flowers that resemble the shape of an umbrella.
I’ve been thinking a lot lately about layers of awareness. That’s my most concise name for the idea so far. It comes from reading On Trails by Robert Moor, an examination of how and why living organisms create, expand, and maintain trails, from humans to ants to elephants.
They didn’t concern many plants, but Moor’s experiences have me pondering how much of daily reality I’m truly aware of, or unaware of. I’m not talking about the movement of the planets or a conversation thousands of miles away. Rather, it’s the things I see, hear, smell, touch, travel through and around and about that I just don’t register consciously.
Consider this: each spring and summer day, we breathe in more than a million pollen grains from dozens to hundreds of plant species. Our bodies answer them—or don’t—with watery eyes, sneezing, and other allergic symptoms. And yet, I don’t know what my cells know. I can’t tell you which individual plant produced any particular grain of pollen.
Just the same, you can pass by thousands of plants and only notice a handful. Oh, that looks like a geranium over there. The butterfly weed is looking good this year.
Vegetation monitoring fills in the gap. It pays deep attention, tracking changes in the presence, abundance, and coverage of plants over time in a systematic way. It samples species we already know of in a preserve and captures those we don’t. This information gives us reference points for what high-quality and degraded plant communities look like. It also points toward what land management techniques work best for those communities.
This all seems so obvious. Maybe it is.
But along with the program’s practicality comes inspiration. Vegetation monitoring adds more layers of awareness to the plant pile. Watching it is seeing humans trying to understand nature better in order to help it better. That’s something I’ll always be interested in.
It’s certainly worth part of a midsummer morning. The Plant Team sampled 12 plots in four hours. (Only 38 to go.) We all wanted to stay out longer, I think. But as they tend to do, other obligations pushed in from their time slots later in the day.
Cleanup was easy. Pati, Ken, and Pete rewound the tape measure, secured the data sheets inside the clipboard, collapsed the quadrat, made sure nothing was left behind.
We hiked back to the trail, then the parking lot. I swapped my soaked-to-the-socks, muddy boots for dry shoes—always satisfying.
And, before we said farewell, the Plant Team undertook perhaps the most hopeful act of the day: planning the next time they could gather and monitor again.