Strawberry plants grew on the green roof at Aquascape in St. Charles. Of all the things Ed Beaulieu showed me in mid-September, that stopped me.
They weren’t part of the original prairie plantings in what’s billed as the largest sloping green roof in North America at 3 1/4 acres.
My guess would be from birds, either dropping them or in their droppings.
Beaulieu said they have such birds as Canada geese and killdeer.
“It’s safe,” he noted, “There’s no predators of them up here. There’s all types of pollinators.”
I asked if any mammals were found. He said no and scholars have documented what is there. I was hoping a hawk or owl had dropped a writhing rabbit or vole that survived.
A green roof or living roof is plants in a growing medium on a roof. Beside havens for birds and pollinators, green roofs insulate buildings and mitigate other climate-change impacts, too.
Ford Motor Company sparked growth of green roofs with what was then the largest in the world in 2003 at its Michigan truck factory. Since then, green roofs in the United States jumped from dozens to thousands.
Beaulieu, dubbed the “Pond Professor” by an interviewer years ago, described how their multi-leveled system works.
There’s the rubber membrane of the roof itself. Then a drainage panel on top of that, topped by 6 inches of soil.
“So what happens during a rain event, the soil will soak up the the initial percentage of water,” Beaulieu said. “Once it exceeds the holding capacity of the soil, the water will start dribbling through and it will hit that drainage panel. The drainage panel is basically a hollow space between the soil and the roof itself. The water will start to migrate underneath everything until it reaches this drainage gutter system. This will allow the water to dribble itself all the way into the retention pond.”
When I visited days after 5 inches of rain, water was not puddled on the roof. The system drains the soil quickly and prevents puddling, but also has baffles underneath to slow water, “so it’s not just a free flow of that training down.”
Going to sedum helps keep biomass (weight) down. So does the specially designed light airy growing medium. Aquascape experienced a roof collapse years ago. Green roofs are more than piling soil on a roof and throwing down seed. The weight of soil, water and biomass must be calculated for the weight-bearing of the roof.
Aquascape started with prairie plantings, which was quite colorful. But most prairie plants tend to have extensive root systems. Now the go-to plantings are sedum. That’s what Aquascape seeded this summer as well as some plantings around the edges. Sedums are very drought tolerant and resistant to foot traffic.
There’s an innovative spirit to doing green roofs. They had considered doing a prescribed burn of the earlier prairie plantings, but that idea was nixed completely. Too bad, I can imagine Rock Master Scott & the Dynamic Three as the backing music.
I digress.
It was time.
Back to the lift, then buckling into a harness (insurance reasons) with Beaulieu and photographer Kevin Koval, for the 40-foot ride down.
After we were down, Beaulieu, first pond designer and installer to receive the “Watershaper of the Year” award, then gave me a tour of their new AquaGarden. I find their integrating water into gardens soul soothing and visually restful.
We finished with a tour of multiple aquariums filled with turtles of all sorts and koi, open to the public during business hours (aquascapeinc.com).
