With a razor-thin budget and just two employees, Brian Campbell, director of horticulture, was struggling to mow and maintain the 50 acres that comprise the Knoxville Botanical Garden and Arboretum.
That, coupled with an idea he’d been kicking around to have a natural wild area, spurred him to make a radical move. He deliberately stopped mowing an isolated corner of the grounds, about 15 acres.
When he tested a 10-by-10 plot of the field for invasive plants, he found that it was only 35 percent native.
“And that’s bad,” Campbell says.
Even after years of encroachment by aggressive non-native species, the U.S. national average in the lower 48 is still 80 percent native. The botanical garden’s high non-native content is probably due to the fact that for 200 years the area was used to propagate ornamental plants as part of the Howell Nursery.
So Campbell started wondering, “What if I tried to replant the meadow in natives?”
To the best of his ability he has been weeding out aggressive invasives (Bradford pear is the worst, he says), planting natives, and mowing paths through the meadow so visitors can wander around in it.
Sometimes the issue of what’s native or not is murky. Chicory, brought over by Europeans, has been here since the 1600s. Queen Anne’s lace, brought over around the same time, is an important food source for orchard bees.
“What I am doing is really prairie restoration,” Campbell says. “If we were to allow it to go truly native it would revert back to a forest, that’s the natural state around here. The meadow is artificial in a way because we are suppressing trees.”
Campbell says since the rewilding experiment, the wildlife population has shot up. He has a well-established family of red foxes, deer, turkey, field mice, rabbits, black snakes, and hawks. The hawks are good at keeping the stray cat problem down, says Campbell, owner of three pet cats himself.
What’s so bad about feral cats? Cats are not natural predators here, and are devastating to songbirds.
“It bothers me to see the dead songbirds,” says Campbell. “They don’t even eat them, they just kill them.”
Before the meadow, packs of feral dogs roamed the area. One bit Campbell a few years ago. Since the meadow, the wild dogs have disappeared. Campbell hasn’t done an official study, but he believes the meadow attracted coyotes, who ran off the dogs. Coyotes are nocturnal, native, non-aggressive animals, unlikely to bite visitors. Campbell never sees them, but does see evidence of them. He thinks they arrived at the botanical gardens by way of the Williams Creek wildlife corridor.
To an untrained eye, the meadow looks like a field of weeds. But each native “weed” Campbell has planted plays an important role in the life of a butterfly or moth. Butterfly weed, for example, is a species of milkweed with nectar-rich flowers, an important food source for larval monarch butterflies.
“If you don’t have milkweed, you don’t have monarchs,” Campbell says.
In fact, the official name of the meadow is the Butterfly Conservation Meadow. This fall will see the completion of the Butterfly Interpretive Garden, an entrance to the meadow landscaped with showy native flowers identified by signs.
Campbell has also started a native fruit trees grove with persimmons, black cherries, and paw paws. Paw paws, tropical-looking native trees with a fruit like a mango, host the zebra swallowtail butterfly, the Tennessee state butterfly.
When school groups come to visit the nearby Every Child Outdoors Vegetable Garden, the kids often wander off into the meadow to play. They can run wild outside; there is nothing they can really mess up or destroy.
Campbell is excited about plans for a nature-exploration outdoor classroom, but currently lacks funds to make it happen.
“I love to show people that project [the meadow] more than any other on the property,” Campbell says. “It’s interesting, constantly changing, an uphill battle. There are lots of small victories, seeing the wildlife coming back, seeing thousands of birds in the morning. I love talking about it. I could talk about it all day.”