Happy highways - part of a biodiverse future for Ontario?

As the snow blows in off Lake Huron and wild turkeys drop by for a feed, James Corcoran is preparing for a new phase in his working life – retirement. Expect it to be busy and enjoyable, as he concentrates on his tree nursery, Hoanaadia in Grand Bend, where he specializes in growing Eastern Hemlock from seed.

It will certainly be less hectic than his career with the provincial government: Corcoran is retiring as roadside vegetation manager for the West Region (Southwestern Ontario). He’s been the only one occupying that position in all of the province, there’s no similarly specialized person in the other four regions. Fortunately, he’s not the last. He’s presently being shadowed by his replacement - and took time to talk about his work at a recent online meeting of the Ontario Phragmites Working Group.

It's a job that became a lot more complex in recent years, he says. Blowing snow sweeping across the over-cleared flatlands of the southwest has created dangerous winter driving conditions. “All those thousands of acres and no forest to stop them - it’s led to frequent highway closures, particularly on Highways 4, 6 and 21,” he says. “The amount of snow that’s being transported is huge.”

Most highway properties are narrow and do not provide the desirable minimum distance to set back treed windbreaks from the roadside. So it's been Corcoran's job to negotiate with neighbouring landowners for the restoration of wider stretches of tree cover to shelter the highways. Windbreaks are a win/win for the travelling public and the landowner, he says: soybean yields in Southwestern Ontario are 25 per cent higher and corn yields are six to eight per cent higher in areas sheltered by windbreaks.

Then there are the invasives that have transformed our landscapes and created wastelands devoid of habitat for insects, birds and other wildlife. The Emerald Ash Borer is an insect that created the need for thousands of trees to be identified and taken down – a task magnified by the fact that in the past Ash trees (Fraxinus species) were the main choice for planting along highways.

And among plants, invasive Phragmites (P. australis var australis) has emerged as the most visible and aggressive of alien species. Well, it appears that the Ministry of Transportation of Ontario has woken up to the problem. Practices to reverse the spread of Phragmites and other invasives are becoming front and centre in operations and construction and the interest and support at all levels are very encouraging, Corcoran says.

Just as well, because Ontario inadvertently set itself up for the phrag invasion and it’s high time for a change of direction.

First there was the Standard Roadside Mix, the same combination of Eurasian grasses that's been used in lawns across North America since the 1950s. This is the one offered by General Seed Company: 10 per cent Kentucky Bluegrass (Poa pratensis), 52 per cent Creeping Red Fescue (Festuca rubra), 5 per cent Perennial Ryegrass (Lolium perenne) and 3 per cent White Clover (Trifolium repens).

Another contributing factor was the Ontario Weeds Act that, from the 1960s to the 1990s, required mowing and spraying with broadleaf herbicides.

Then came Mike Harris, elected premier in 1995, who privatized highway maintenance. Gone were the teams of landscape management staff.

Conditions were ideal for opportunistic invasive Phragmites and other species to make a move into areas of weak shallow-rooted Eurasian grasses.

Corcoran is a professional forester with experience in the plant nursery industry before he became a civil servant. A West Region senior environmental planner, he started specializing – and found that the job grew as others came to him for advice on what would grow where. With help and support from many in the Environmental Section and across the organization, a transition began, towards restoring the landscape with native species.

Corcoran told the OPWG meeting how he drove up the Bruce Peninsula to Tobermory this past summer, where a concerted effort of targeted spot herbicide treatments began several years ago, to eliminate Phragmites before it became a serious problem. Along the length of Highway 6, he found only one phragmites plant. The program had been an unqualified success.

Naturally those in attendance at the meeting – phrag phighters all - were enthusiastic, and became even more so when Corcoran explained how, in comparison to the Eurasian grasses, native grasses and forbs are sufficiently vigorous to withstand invasion, superior in controlling erosion, require less maintenance and “improve the visitor experience.”

He described a five-acre corner of an interchange near Chatham on Highway 401, planted native almost 25 years ago, never sprayed, never mowed, and consequently never invaded.

We’re talking serious pollinator habitat. Here’s the West Region native mix: 85 per cent grass species - Big Blue Stem (Andropogon gerardii), Virginia Wild Rye (Elymus virginicus), Switchgrass (Panicum virgatum), Fox Sedge (Carex vulpinoidea) and Indian Grass (Sorghastrum nutans). And for the forbs, a minimum of eight species making up 15 per cent of the total: Swamp Milkweed (Asclepias incarnata), Sweet Oxeye (Heliopsis helianthoides), Virginia Mountain Mint (Pycanthemum virginianum), Black-eyed Susan (Rudbekia hirta), Blue Vervain (Verbena hastata), Wild Bergamot (Monarda fistulosa), Path Rush (Juncus tenuis), Evening Primrose (Oenothera biennis), New England Aster (Symphyotrichum novae-angliae), Foxglove Beardtongue (Penstemon digitalis), Missouri Ironweed (Vernonia missurica) and Spotted Joe Pye Weed (Eutrochium maculatum).

Yes, but. Aren’t the insects, birds and other creatures attracted to these plantings put in harm’s way when there’s habitat along the verge next to fast-moving heavy traffic?

That’s a question that comes up all the time, Corcoran said when I talked to him – in fact it’s often raised as a concern by those in the industrial landscape sector.

But his observations and those of botanists and biologists he has consulted are that creatures are not inclined to leave an area of food, cover and safety to cross over into a bare, hostile environment – whether it’s the highway on one side or a sterile field on the other.

That’s not to say that there won’t be mortality. “Where you do have a lot of habitat, you will have mortality,” Corcoran says, recalling the way we used to have to scrape layers of insects off our windshields 40 years ago.

At the same time, the native seed mix MTO uses has been carefully selected to ensure that species that may be attractive to deer are not included. Deer do like the digestible Eurasian grasses, by the way.

So, I wondered, is the Standard Roadside Mix on the way out?

Not at all, Corcoran replies, laughing. “It is ubiquitous. I still get pushback, pushback that I believe is from Big Agra.” The agronomic seeds remain the go-to, “colonizing the landscape,” he says, mainly because native seed mixes with 30 to 40 different species are not a good business model. Four easily propagated grasses are much simpler. (If he had the land, he says, he would consider putting it into native seed production.)

But it’s precisely that diversity that makes a native planting vigorous, with a species filling every niche to make a tight network resistant to invasion.

A limiting factor is the availability of seed (not to mention expertise among the private contractors who now do the work in Ontario). The Texas Department of Transportation is a pioneer in forward thinking on this issue, dating back to the 1930s when they started collecting their own local native seed. Check out this video for an inspiring view of what a highway verge should look like.

In Ontario, the native mix is being used on newly constructed highways – but the rollout takes time. Corcoran estimates 100 kilometres have been planted in West Region, with another 100 in the works. Fortunately, the native plants do a good job of spreading their seed and extending the coverage, he adds.

There’s still a way to go before the verges of Ontario highways become places of beauty and home to pollinators. But the transition will be worthwhile based on reduced maintenance costs as well as recovering biodiversity.

Contact your MPP to urge that qualified vegetation specialists with a background in ecology or forestry be hired by MTO in all regions to improve highway management and restore the vitality of our ecosystems.

Postscript - a couple of other native roadside mixes:
OSC Seeds
St Williams
Marlaine Koehler
- 2 February 2023 at 11:19am

What a fantastic story Kate! Thank you for sharing Mr. Corcoran's determination to find ways to make highway corridors function in a positive way for our ecology. His work is another great lesson to never underestimate or give up on finding ways to make every part of our world work greener.
- 2 February 2023 at 05:07pm

Thank you Kate! Wonderful story and information :)
- 13 March 2023 at 02:48pm

Really interesting story. Answered the question I often wonder about, and that is an increase in mortality of highway verges. The point of all the bugs that used to get killed on windshields as a kid was a great comparison.

Silver Aleta
- 22 April 2023 at 11:06am

What an amazing story Kate! I was actually looking for pieces about highway biodiversity that talk about the seeded grass, wondering whether we'd be able to improve it, and finding this was very lucky! Thank you.
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