As published in The Southeast Journal August 22 to October 24, 2019
August 22
I live in Silver Plains, a loosely defined area in the RM of Morris that is intersected by PR 205E. The CN rail line that runs beside PTH 75 from Winnipeg to Emerson is 140 metres west of us.
Over the years, CN has had troubles with snow accumulation on the tracks. And, snow build up where the tracks intersect with 205 has often made the highway virtually impassable. I’ve watched as rail crews cut down willows and mowed tall vegetation beside the tracks to reduce snow collection there. This was not working. So, someone at CN decided to spray a metres wide swath on both sides of the tracks with a potent herbicide. This was a couple of years ago. Next to nothing was growing adjacent to the tracks the first and second year. At the end of last year some plants emerged. Now the sides of the tracks are lined with creeping thistle*, Cirsium arvense. It’s as if CN seeded the plant. During a recent drive to Winnipeg I saw that these rows of thistles extend all the way to the City. And, I was told they go to the border as well.
When I first saw all the dead vegetation beside the tracks I thought, “This is obscene.” When I see what is taking over the thought which comes to mind is, “This is criminal.”
Now, I read on CN’s website that this practice is to be continued. Apparently they are interpreting a directive from Transport Canada which says “vegetation on railway property which is on or immediately adjacent to roadbed must be controlled.” Spraying with herbicide is a convenient solution. The window for this year is July 6 to September 11. Unfortunately for all of us creeping thistle has already set seed and will continue its spread around the area.
There must be a better way.
*Creeping thistle is what many people call Canada or Canadian thistle. The latter appellations are misnomers. Cirsium arvense is from Europe and was accidentally introduced to NA back in the 1600s.
August 29
Imagine for a moment that "we" could have CN Rail charged with a crime because of the creeping thistle growing alongside its rail line. They would have an easy defence: "Your Honour, the plant is growing everywhere in the vicinity." Indeed, it is. From coast to coast to coast. Meanwhile, many people would be happy to not see this "weed" (and many others) growing nearby.
Before continuing, I need to clarify some terms. A "weed" is a plant growing where it's not wanted. If you planted creeping thistle in your garden, to you, at least, it would not be a weed. Hence, calling this plant (and others) weeds is inappropriate in this context. In naturalist terms the plant is exotic. (Sexy though it sounds, exotic means "from elsewhere".) Such plants are also called introduced, foreign or alien. Plants growing here prior to Europeans coming to North America are considered native. The rest are exotic. Early settlers mistakenly did not get rid of many exotic plants when they first appeared on this continent.
Along with well known exotic grasses there are many exotic forbs (flowers) growing in ditches and unused fields: fringed loosestrife, black medic, an assortment of clovers, sow thistle, birdsfoot trefoil, etc. In 2003, when I first moved to these parts, leafy spurge, Euphorbia esula, was not noticeable beside the highways. Now, every year there is another patch or three of this troublesome plant which forms exclusive mono-cultures and is difficult to remove.
Some, in positions of influence, have indicated all of this is the "new natural". But, this assessment misses something affecting all of us. It's called "shifting baselines", a condition first noticed 50 years ago by landscape architect Ian McHarg. In essence, what each of us grows up with is what we perceive as normal. We have all grown up with creeping thistle and many other exotic plants growing in abundance around us. Many are now considered to be naturalized,
Well, I've got to tell you, it's not natural to me. And I see a different normal in my mind's eye.
September 5
I was encouraged to read recently on Facebook that someone else (who belongs to a group which I follow) is doing what we have been doing to eradicate exotic plants. Coincidentally an article was published on CBC's website about tall waterhemp, a new troublesome exotic; a tier one weed. There is mention that this plant is resistant to most herbicides—yikes—but no mention that it's an annual; that it grows from seed each year not from last year's growth.
Annual plants are the easiest to remove. We have curled dock on our site from time to time. We prevent its spread by pulling it before it flowers and sets seed. No seed means no new plants next year. Perennial plants, of course, are not so easily removed from the area. They come back year after year. So, too, some biennials which start one year and flower the next.
Like all lifeforms plants have lifespans. Some are one year, others are two or three and some up to twenty years. (And. there are trees which live for centuries.) The point here is it's a numbers game. Each plant which produces seed may propagate itself. Regardless how long lived a plant is, preventing it from producing seed will, at some point, get rid of it.
White-flowered variant of creeping thistle.
As my FB acquaintance is doing, we go around our site and take the flowers off plants we don't want. I think of this as the "attrition method". It's a slow process.. But, more importantly, what's growing next door or down the road is problematic. It's windy out here and there are birds in the area. (Goldfinches love thistle seed.) Hence, the creeping thistle being curtailed on one site may be replaced as a result of someone else's neglect. Obviously, we are in this together.
September 12
Mowing is a variation of the "attrition method" to control vegetation. BellMTS, which leases property adjacent to us, has the site mowed each year to curtail exotic plants growing there. RMs and civic governments across the continent oblige people to, at the least, mow their properties, in part, for this reason.
Some years back I crossed paths with a Councillor from the RM of De Salaberry. He's also a farmer. (I helped him load grain into rail cars which were dropped at the siding on the tracks just west of us.) On one occasion, we talked about yards and ditches being mowed. When I mentioned “weed” control as the motivation he interjected, "It's for beautification." He laughed at the look on my face. In the "eye" of this beholder, mowed areas are aesthetically bland. (Ah, but what does an artist know about beauty?) They're also environmentally inert.
If you drive north along PTH 75 from RD 11N (north of Letellier) you will see a stretch of virgin prairie (as it's called) on the east side between the highway and the rail line. It is beautiful. There's a reason it remains. The tracks were put in place before exotic plants showed up in these parts.
Virgin prairie north of Letellier, July 24, 2011.
F. P. Grove (in FRUITS OF THE EARTH, 1933) writes: "One trouble was that the water [from a flood] had spread seeds of foul weeds all over his land. Where the prairie remained unbroken, the grass had held its own ... But ... where his crop was seeded, a damnable mixture of charlock, thistle, and tumbling mustard had sprung up with the wheat."
September 19
At the risk of belabouring the point here, a staffer at Manitoba Infrastructure told me, "Ditches are mowed to prevent trees from growing alongside highways." There is a better way to do that. Burning. (More on this later.)
For the moment, regardless of the reason(s) for it, mowing is problematic with respects to what is growing in ditches and alongside rail lines, etc. It gives the illusion of keeping vegetation under control while it only sweeps the exotic mess under the proverbial carpet. It also prevents many native plants from proliferating. Yet another reason for mowing is to prevent snow drifts on highways. But the timing is such that exotics are encouraged while many natives are not.
When I first moved to Silver Plains, in 2003, I saw lots of big bluestem growing alongside highways. Each year since, the numbers have decreased, especially beside the shoulders, because a metres wide strip is mowed before the “provincial grass” sets seed. What many don't seem to know is that native plants have seasons. Goldenrods and sunflowers are almost finished; asters will be pollinated in a couple of weeks. Big bluestem is a warm season grass which is pollinated around mid-August. Six to eight weeks later its seed is ready. Mowing in September puts its seed on the ground before it is viable. Meanwhile exotic brome, quack and Kentucky blue-grass, etc, set seed earlier in the summer. Inadvertently the exotics are given a hand up. In the RM of Stuartburn mowing is delayed until mid-October in areas where warm season plants grow beside the highways, Since the first snowfall arrives later and later each year, mowing to prevent snow drifts could be delayed without ill effect.
Incidentally, the air temperature above the mowed area is 2° Celsius higher than above the not mowed area.
September 26
Prior to European settlement, most of North America was burned regularly. Watch “Tending the Wild” an hour long video on Youtube (based on a book by M. Kat Anderson) which discusses the topic. (Talk about fire suppression starts at 6:00.) Apparently American Indians noticed plants grow better after burning.
On the grassland, burns were generally done every two or three years in the early spring or late fall. Forests, too, were burned although not as frequently. Doing so helped hunters see game and, by virtue of clearing out leaf litter and seedling trees (which would lead to too many trees), regular burning prevented conflagrations which wipe out forests. (Burning highway ditches would prevent trees from getting started there.)
We started replanting our site to native in 2007. Fire, being part of native plants' ecology, got me started learning how to burn. I first did this in the highway ditch out front. It was a safe place to learn. With all the other things to do it was usually mid-June when I got to it. After six or so years of doing this every year I read that burning at that time of year, every year for five or six years, was the best way to eradicate creeping thistle. I checked. The plant was gone from the ditch.
Unfortunately, because it is growing on the other side of the highway and adjacent properties, creeping thistle has returned. While continuing to burn every year, I now go around with a grass whip and remove flowers on unwanted plants across the road and 60 metres east and west of our site.
It occurred to me that an experiment is in order. What if a larger area could be burned? The result of CN's action prompted me to develop the proposal which follows next week. Perhaps there is a better way to satisfy Transport Canada's edict to “control vegetation”.
October 3
Transport Canada tells rail companies that “vegetation ... must be controlled.” Manitoba Infrastructure and the RM of Morris control vegetation alongside roadbeds. But many undesirable plants continue to spread in the region. And native plants are in decline.
Based on my experience, at least one exotic plant can be eradicated by burning in late June. Other exotics are curtailed; they grow back but do not produce seed. To see if we can alter the vegetation over a larger area I propose that vegetation be burned in the highway ditches and alongside rail tracks one mile in each direction from the intersection of Silver Plains Road (RD 7E) and PR 205E. There are wide stretches of CN owned land on both sides of the tracks and RM owned lots adjacent to our site which should be burned as well. Burning the stretch along PTH 75 would test the practice on a major thoroughfare.
This image was not printed in The Southeast Journal.
A number of parties control this land. Participation of Manitoba Infrastructure, the RM of Morris, CN Rail and BellMTS is required. Three “neighboursOne neighbour has already said to me, "Sure, burn my ditch."” may wish to participate. Scientists (from the University of Manitoba) should be included to establish criteria and monitor results. And I will join the mix.
The initial eradication burns would have to happen every year for at least 6 years. Seeding native plants and beginning maintenance burns would extend the time-frame to 10 years. The area specified is low risk in terms of possible property damage. While there are a lot of hydro poles, they are easily dealt with. The Rosenort Firehall is 8 km to the west.
I have corresponded with scientists who indicated this appears to be a worthy experiment. However, I have neither the means nor clout to make this happen. Hence suggestions are welcome as to how this is accomplished. Next week I will discuss some of the particulars.
October 10
In proposing a method to suppress exotic plants and give native flora a hand up, it's important to note that fauna will be affected by this. There are many birds, mammals, amphibians, insects and spiders which use the vegetation before, during and after the timing of green burns (as I think of them). One scientist has suggested scouting for bird nests and working around them each year. Meanwhile, green burns move slowly. Frogs, from what I've seen, are able to hop out of the way. Whether things are done, like cutting milkweeds beforehand to prevent the first generation of monarchs from depositing eggs would be up to the team that forms to implement this experiment. (Fortunately, milkweeds are plentiful in this region.)
Some cool season native plants will not grow back when burned so late in the year. While there are a number of native plants (including big bluestem) presently growing beside both tracks and roadways, they are not cool season. Another unpredictable variable is the seed bank. Exotic plants have been growing in this area for decades. Many may continue to germinate for some time. As such, continuing the attrition method—preventing seed production—may be required as the less competition for natives at the end of the period the more likely they will take over down the road.
Scheduling burns is not easily done. Timing is dependent on the weather. Low humidity and low wind are required to burn and do so safely. This requires a flexible crew who can respond on a day's notice. Water is best for extinguishing fire. There are several dugout ponds in the specified area. And, crops must not be damaged. As the photo illustrates it is possible to control burns.
controlled burn ~ June 28
October 17
Since I’ve mentioned seeding native flora to begin a process of succession, it’s worth pointing out that there are a number of native plants which grow short. The local native ecosystem—Tallgrass Prairie—has an under storey. Saltgrass and scratch grass are sod-forming, grow six inches long and tend to lay flat against or near the ground. Several forbs are ground cover: perennials silverweed, wild strawberry and spotted sandmat stay low. Their leaves cover the ground when top growth dies off in the fall, often preventing seed of other plants from touching the soil. These and some others could be seeded along shoulder edges.
saltgrass | silverweed
As well, all of the plants growing near shoulders—whether short or tall—can be flattened rather than mowed.
flattened tall grasses
October 24
Some time ago I read about a US State Supreme Court Justice overturning a law. His ruling started with “whether by accident or by design”. In his view a new law was having a negative impact, hence his decision. Most people are not aware that essentially two types of plants are growing in this region. As such, the effects of current practices are accidental. It makes sense, though, to design an approach to “controlling vegetation” that is low maintenance and possibly self-maintaining.
There is more to this than just curtailing exotic vegetation. Most agree that reducing carbon dioxide in the atmosphere is a good idea. Recent research indicates that native grasslands store more carbon than forests. (Search “carbon sequestration tallgrass prairie”.) Plus, grasslands store the carbon below ground while forests store it in their top growth. As such, forests release more carbon into the air when they burn. And, the exotic herbaceous plants—which currently dominate in this region—do not sequester much, if any, carbon. Restoring carbon sinks is the other side of reducing carbon dioxide in the air.
tallgrass prairie
One last detail should be factored into this experiment. Along with keeping track of the cost to induce a transition from exotic to native flora, a cost analysis should be done to compare the cost of controlling vegetation with periodic burning and flattening (where required) versus what is currently being done. Who knows what the numbers will say? It may cost less.
I once visited Lake Itasca in Minnesota. While there I stepped over a narrow stream. A nearby sign said it was the head water for the Mississippi River. Allow for the moment that this experiment works.
A thank you to Brenda & Don Piett for publishing these articles
in The Southeast Journal.
Additional information and elaboration of the particulars and details is available by contacting me.
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