Ecology

The Amazing Mystery of the Bicknell’s Geranium

By October 26, 2018 No Comments

October 7, 2018
WATERTON LAKES NATIONAL PARK, Alberta

Part two of our report on last fall’s big fire.

Photo by Edwin Knox

Nadine and I, along with our old friend Edwin, are walking through charred aspen groves on our way to Lakeview Ridge. All around us is a forest of young aspen shoots as high as our knees, sometimes as high as our waists! It’s an exuberant and joyful explosion of life.

Buffaloberry growing back from a taproot that survived the heat of the fire.

We are in the middle of a forest burned in 2017’s intense Kenow Wildfire. About half of Waterton’s vegetated landscape was scorched in the fire, but in the Canadian Rockies, plants are built tough! Lots of species are adapted to come back from these moments of destruction.

The aspen are joined by buffaloberry bushes, sprouting from their deep rootstock. In a year or two, once the bushes start to yield fruit, they will become a key source of food for black bears and grizzlies.

Western showy aster going to seed

And there are fields and fields of western showy aster. It’s got a great Latin name, Eurybia conspicua, and boy, is it ever conspicuous! There are millions of plants and their puffy seed heads are sporting billions of seeds.

Among these familiar sights, however, is a plant that none of us have ever seen. It’s everywhere, growing close to the ground, and we three “park experts” are in the dark.

You can see why this geranium is nicknamed a “crane’s bill.” Photo by Edwin Knox

At dinner, we go to work to figure out the story behind the mystery plant. First we use Job Kuijt’s epic plant guide to Waterton to discover that our mystery plant is called Bicknell’s Geranium, AKA crane’s bill.

Then it’s off to the internet, where we learn that the seeds of the geranium physically explode out of those crane’s bill seedpods in autumn. They can then stay dormant in soil for centuries, and will only germinate after a fire.

In one study, from the Boundary Waters area of Minnesota, seeds in a 270 year-old forest sprouted after a fire. In a greenhouse test, almost all of the seeds germinated after 10 minutes exposure to temperatures of 65-100° C (150 to 210° F).

The leaves of the beautiful Bicknell’s Geranium. Photo by Edwin Knox

This plant loves fire! So why had none of us seen it before? Well, once the other plants and trees start to recover, the Bicknell’s geranium disappears. In some forests, it can cover 25% of the forest floor the year after the fire, but in three to five years… it’s gone.

But it’s not really gone. It leaves behind seeds, and they wait for the next fire, even if it is hundreds of years away.

The forests of Waterton look ravaged, but life will return…