Skip to main content

Soiling City Sections with Native Plants

Ben Porchuk

Can you think back to the last flood in your city? It seems like every other year here in London, ON, or Toronto that a damaging flood hits in the late spring or even in the dry summer. Headlines and news images show cars barely making it through some of the lower roadways for the water over half way up walls of the tires. These images are frequent and often called ‘flash floods’ from big thunderstorms that have rolled in. Climate change has indeed created more extreme weather events and yet it’s the lack of plants on the landscape that has created the floods and the ensuing erosion.

“But there are landscaping trees scattered all throughout the city, Ben.”

Outside of our important and crucial valleys that are natural and semi-natural, we have landscaped trees throughout the city; an average of maybe 50 per acre of available area only, with few if any shrubs, and even fewer herbs (forest flowers, grasses, ferns, etc.) because of the concrete, asphalt in the roads and sidewalks and of course the area the buildings take up. A mid-aged forest would have about 500 trees per acre, thousands of shrubs and tens of thousands of ferns, forest flowers and extensive underground networks of hundreds of species of fungi. So instead of about 25,000, we have 50 plants per available area which is usually along narrow boulevards or in manicured parks.

These plants are sponges for they not only hold water in their ‘bodies,’ but in collaboration with the fungi they ‘host’ around their roots, they provide channels for water to flow vertically from rain drop to below soil surface without washing the soil away. This is because the plant roots systems also support diverse and extensive populations of bacteria that form a strong glue between the plant roots and surrounding soil. Even further, each native plant in the ecosystem attracts different species of fungi and bacteria to their root systems. This diversity below the surface is far greater than number of plants above by a magnitude of millions. We know this soil diversity is critical for maintaining the ecosystem, but really, our knowledge the significance and importance of soil really scratches the surface. Though these seemingly complex but naturally simple interactions, plants are the quarterbacks with their receivers and defensive lineman (bacteria and fungi) working in unison to build soil back to strong, resilient, and diverse ‘earth blanket.’

What can we do? Add more native plants. It’s that simple. We need to expand the dialogue with municipal planners, other leaders, and politicians. It’s an easy argument because more plants means more beauty, more oxygen, and BILLIONS saved on flood and erosion prevention. We don’t need to start with an entire city, however. Could you imagine how that dialogue would go? Let’s start with a section of a boulevard maybe, and find a way to do it right. Showing this, will help us expand upon these great starts and who knows, maybe in a few years, we could have entire neighbourhoods planted with so much more diversity….