Moore Park - Brick Works

Sights & Sites: Sheila R. Colla

Sheila Colla has lived in Toronto her whole life. She is currently an Assistant Professor at York University in the Faculty of Environmental Studies where she researches the conservation of declining native species including bumble bees. She is a co-author of The Bumble Bees of North America: An Identification Guide, Princeton University Press, 2014

I asked her the question: What is the most interesting, unusual or beautiful sight to see in one of our ravines or forests?"

One of my favourite plants to come across in Toronto is Orange touch-me-not (Impatiens campensis). It is a common native plant found growing in moist soils along creeks or in ditches at many sites in Toronto. Most recently I found it along the path behind Evergreen Brickworks. Here below are the reasons this plant give me joy:

a) Flower shape- The flower is unusual with its large opening and long tapered nectar spur. This shape is likely the result of millions of years of coevolution with its key pollinators- hummingbirds and long-tongued bumblebees. The pollinator has to stick in it's beak or tongue deep into the flower, getting covered by pollen in the process. By producing nectar at the base of the long spur, Orange touch-me-nots attempt to avoid the nectar being taken by pollinators which may be less efficient. But some insects have figured out another way. If you look at the back of the flower you may see it has been pierced by a "nectar-robber"- a short-tongued bee (like the Large Carpenter bee, Xylocopa virginica) which bit into the flower to suck out the nectar.

b) Bursting pods- It's common name 'touch-me-not' likely comes from the projectile seeds which burst from ripe seed pods at the slightest touch. This adaptation allows seeds to disperse away from their "mother" plant to have a better chance of getting sunlight. Bursting pods is a fun pastime for children and adults alike. Try it, the surprise does not get old!

c) Hummingbirds- What more can I say. Any plant which attracts hummingbirds for my viewing pleasure is a winner!

d)Unassuming but beautiful- The plant represents so much of what I love about native wildlife in Ontario. You may have walked right by it without realizing it as the flowers are numerous but small. Their colour varies from pale orange to almost red- burst of bright spots in an otherwise green bush. When you do stop to notice it and closely observe it, you get a glimpse of its ecological role, relationships with other species and its evolutionary history.

Photos at the top of this post courtesy of Sheila R. Colla.

Posted on: September 22, 2015
This post is part of Sights & Sites, a series that celebrates our amazing ravines & forests and the people who care for them.