If you ask Dave Shepard, prairies get a bit too much credit around here. He’s a tree guy, and he wants to make sure the area’s ancient woodlands get some recognition too.
Ancient forests in this part of the Prairie State?
Indeed, he said. In fact, he contends there are tree populations in Will and south Cook counties that point to an era some 8,000 years ago when the climate here was warmer.
On his forays into the woodlands over the last 40 years, he’s come across some trees that stand out from the rest, so Shepard, a Homewood resident who previously lived in Riverdale, went out of his way to get them some statewide credit.
This year, those efforts were rewarded as two trees he nominated were declared Illinois Big Tree Champions, certified by Illinois Extension and listed on the Illinois Big Tree Register.
Shepard, an environmental science professor at Moraine Valley Community College in Palos Hills who has also taught at Governors State University in University Park and South Suburban College in South Holland, found both of the newly crowned champions at Messenger Woods in Homer Glen.
The new state champion black maple there stands 118-feet tall with a 32-inch thick trunk diameter, while the state champ jack pine tree is 83-feet tall with a 19-inch trunk diameter. Other factors, such as canopy spread, factor into the rating system.
Much smaller, but still large enough to be a state Big Tree Champion, Shepard identified an inland serviceberry tree on the South Suburban College campus that’s 34-feet tall.
Shepard’s three champions join a group of Chicago area giants that include 70-feet tall slippery elm at St. James at Sag Bridge Cemetery in Lemont and a National Champion Ohio buckeye growing near the Hyatt Lodge in Oak Brook. Private lots in Aurora are home to Illinois Champions American elm and American beech, and the Morton Arboretum in Lisle is home to three state champs. Others are in St. Charles and Geneva, and two champs are growing in Midway Woods in north Cook County.
What makes Messenger Woods in Homer Glen such a good place is the thick layer of organic material that’s been allowed to build up at the oldest preserve in the Forest Preserve District of Will County.
“It’s like walking on a water bed,” Shepard said. “It’s an old woods.”
By his estimation, Messenger Woods dates back much further than its acquisition in 1930, and he speculated that Indigenous people were extracting sugar from the black maple trees there since prehistoric times.
That long view, the connection with the distant past, is one of the reasons Shepard has for decades traveled off trail in search of interesting trees. It led him to the area’s only two populations of black maples, a tree more at home further north, according to information from the Forest Preserve District of Will County. Besides the Messenger Woods colony, another stand of black maples can be found in Black Partridge Woods near Lemont.
“I’m always looking for stuff. I like identifying things,” Shepard said. “I get awe inspired when I look at the height of these things. It’s like its own world in there. When you walk into the woods, you can think better, you can pray better. You can commune better and you can see things, the way things were. It’s like going back in time.”
The convergence of historical landscapes in the Chicago area, particularly in the south suburbs, also gives every outing the potential for discoveries, Shepard said.
One mystery that draws him back to Sweet Woods outside of Thornton was a sourwood tree first recorded by botanist Floyd Swink in 1956 that shows up again in the scientific record through specimens collected in 1973.
“That’s exceptional,” Shepard said. “It’s a beautiful tree that turns red in the fall and has white flowers like a lily of the valley, but as a tree.”
Shepard hasn’t been able to find that tree, but he thinks it could be an outlier, a relict from environmental conditions that existed long ago, as sourwood trees occur naturally in Illinois only at the state’s southern tip. Otherwise, it’s mostly native to the East Coast and Appalachian Mountains regions.
The official assumption, Shepard said, is the sourwood was planted by someone years ago, but until he finds it and can investigate what trees are growing nearby, he’s not convinced.
He is convinced of the importance of a grouping of tree species he found in Tinley Creek Woods east of Orland Park.
“I found a disjunct, a relict population of southern trees. Trees you would normally see in Tennessee, Kentucky, Arkansas,” he said. “There’s a whole population of them.”
The “15 or 16 species” including rock elm, scarlet oak, Nuthall’s oak, flowering dogwood and white basswood growing between Oak Park and Harlem avenues and 143rd and 151st streets aren’t trees that are supposed to be here.
He collected specimens and put them on file at the Field Museum and proclaimed his discovery to the Chicago botany community.
“They told me Cook County planted a bunch of trees from the South in 1940,” he said. “There’s no evidence of that. I’ve looked at this area for a long time and there’s no way anyone planted this.
“They’re naturally occurring. Trees grow in forest associations. You can tell plantings by the forest preserves because they don’t go together in the wild. Back then, Cook County didn’t care what they put in. They used common trees that were easily available and easy to propagate.
“These same trees growing here grow in the same type of locality 300 to 500 miles south of here. It’s hard to get to. It freaked me out when I saw it. They’re growing up together. You’d have to be a genius botanist to put this together.”
Instead of celebrating the discovery, the trees were dismissed as “exotics, invasive species,” Shepard said.
His research indicates the species not only aren’t invasive, they could predate many of the surrounding, native species of white oak and hickory.
Survey maps dating as far back as 1821 indicate the area was part of a larger grove, and though records indicate such uses as cattle grazing and timber harvesting, there’s nothing that states the area was deforested.
Shepard posited that the disjunct points to an ancient forest “that existed on this Tinley moraine for several thousand years,” when the climate here was warmer.
A worldwide weather phenomenon called the little ice age that cooled the climate for centuries starting around 1300 gradually forced many formerly native species south, he said, leaving these small relict populations behind where conditions and perhaps some hybridization allowed them to survive.
There are other cases of disjunct populations that came to be accepted, such as prickly pear cactus, natives of the American Southwest that continue to hold on naturally in the Chicago area.
His next step is trying to get a paper about the Tinley Creek trees published through the Illinois State Academy of Science, as it would add impetus to is protests against restoration practices that could result in the removal of the southern trees as weeds.
In the meantime, he’ll continue exploring south suburban forests and teaching his students about the great diversity in the area’s woodlands.
“We need to preserve woods like these,” Shepard said. “They are historical documents of what was there before we were here.
“A lot of my basis is this is God’s creation. We’re stewards of the land. That’s our job. We’re not creators, but we can destroy it.”
Landmarks is a weekly column by Paul Eisenberg exploring the people, places and things that have left an indelible mark on the Southland. He can be reached at email@example.com.