Yesterday, I drove to the Little Rouge River woodland
park to experience Nature for several hours. I had discovered the park by chance
this spring and was totally enchanted by the rich and pristine woodland along
the little river; I now wished to explore more of the woodland’s phenology:
this time draped in fall colours.
It’s a half-hour drive to the woodlands area
from where I am currently cat-sitting. The drive is mostly through suburbia
until I emerge into open country and farmland. The park entrance lies off a
small road with no obvious sign. I park the car and see that I’m the only one
there. Then I make my way to the path alongside the river, noting several older maples, oaks and white willows (Salix alba) along the forest edge. The wind has shaken all the willow's yellowed lanceolate leaves onto the ground; The tall
many-branched trees stand with deeply furrowed shaggy bark that looks like
interlocking ropes; watersprouts spring out of the lower trunks.
The mixed woodland I’m
walking through lies in the Carolinian forest region— a diverse mix of willow /
Manitoba maple / cedar bottomland, with red oak / hemlock / white cedar slopes
and hemlock/white pine/sugar maple/beech/black cherry/red oak tableland. The
path leads me through snaking roots beneath the fresh aroma of pine and cedar.
I make my way toward the banks of the river where beech and maple bow over the chortling
water.
The forest is now a mix of colour. Most of the
deciduous trees have stripped off their leaves in a revealing show of textured grays,
gray-browns and blacks. The bare trunks and fractal branches contrast with the
deep greens of the conifers. Rogue trees—like the oak and beech—still claim
their leaves, adding deep russet tones to the varied grays and deep greens of
the canopy. The forest is now more open, emerging from a soft brown carpet on
the ground.
The air is fresh with the scent of loam,
decaying leaves and saprophyte activity. I have the whole place to myself—that
is, along with scolding chipmunks, scampering squirrels, tapping woodpeckers
and the like.
I am looking for the old sugar maple I’d spent
time with this past spring. After several bends in the river, I see it, leaning
precipitously over the river bank like an old man sharing an intimate story. It
has already lost its leaves; they cover the ground in a soft carpet of maple
leaves. The old tree literally hugs the bank with its roots; like a carved
figurehead hugs the prow of a great tall ship.
Eager to see my old friend up close, I scramble
down the overhanging bank using the old maple’s root “stairway,” then
ungracefully drop onto the cobbles below. I do a scrambling dance not to slide
into the river (that will come later) and gaze at my prize.
 |
| sugar maple with extensive roots on bank |
There it is! My shaggy gnarly old maple. What a splendid
tree! Every part of it is splendid. I gaze up at its shaggy trunk, stretched up
in a long bow, with typical silhouette of branching out arms that every
Canadian kid drew when they were six. I gaze down at the horizontal roots that
stretch out to hug the bank. They stitch the bank together with their tangle of
ropes, keeping it intact.
Science tells me that all the trees of a forest are
really one organism, connected by roots and the microorganisms inhabiting them,
communicating through the micorrhyzae in the ground and the hundreds of
aerosols the trees exhale every second of every day. If you sit long enough in
the forest you will start to feel this too. You will breathe it in. And in
doing so, you will realize that we are all connected and we are all one.
 |
| close up of burl on maple root |
Feeling the need to get to the other side of my
maple, I do a kind of contortion to scramble beneath its bow and get around it.
I stumble through the loose cobble and finally splash into the river as the cobble
rolls out from under me. But I cheer myself; I’ve reached the other side of my
tree. From this vantage, I note several large burls at breast height on the
maple’s trunk and extensive aerial roots. Dead branches drop off healthy trees all
the time, and wood knots appear in the trunk and roots where branches have died.
These burls are the result of self-pruning—particularly on the river-side—when
the tree drops its lower branches as it reaches maturity.
Refreshed
and joyful after visiting my maple, I scramble up the bank and resume my walk
through the woodland. I pass an opened stand of beeches that have left a thick
monopoly of beech leaves on the ground. There are more maples and red and white
oaks—their splendid overall forms proudly revealed. I spot other trees and
shrubs and try to identify each using the tools now presented to me: the bark
of the tree trunk; the overall form of the tree; the now visible branches (whether
they are oppositely or alternately branched); the clues left on the ground in
the litter of leaves, nuts and seeds.
 |
| Old cedar with woodpecker holes |
The
trunk of the Yellow Birch (Betula
alleghaniensis) peel off in curls of amber-gray. I remember my botany professor
at Concordia demonstrating that if you scrape a twig with your finger nail, the
twig emits a strong wintergreen scent.
The
bark of a mature Ash (Fraxinus sp.)
is tightly woven in a distinct pattern of diamond-shaped ridges. The ash tree,
like the maple, also branches in pairs, not alternately. There are, in fact,
few tree groups that show an opposite branching pattern like the ash and the
maple.
The
various species of maple in the Little Rouge woodland appear healthy; they grow
tall in good loam and are thick with leaves and seeds and are surrounded by
healthy community of trees, making up a flourishing and highly functional
forest ecosystem.
But
there are concerns for climate-induced
impacts
on the sugar maple in southern Ontario and Quebec. Concerns that were raised already in the 1950s and have
resurfaced in recent reports of a declining maple syrup industry.
 |
| maple tree on bank of Little Rouge |
In
January of 2018 scientists published a study in the journal Ecology on how the
fate of maple trees is threatened by climate change. The growth of sugar maple
trees will be stunted over the decades by climate change through warmer and
drier growing seasons. Their examination of 20 years of tree and soil data in four
Michigan locations, found that, despite increased nitrogen from agricultural
runoff for growth, lack of water will drive the negative impact on maples
growth.
Lead researcher Inés Ibáñez, ecology professor
at the University of Michigan, used climate modeling to forecast the fate of
sugar maples if nothing is done to curb greenhouse gas emissions. "The
biggest trees will still be there, but won't be growing as much and the little
saplings won't survive, [so] once the older trees start dying, there will be no
new trees to replace them," she says. Sugar maple habitat is at great risk
of decline as well. Scientists have projected
that in southern Ontario, some of the highest occurrences of sugar maple stands
also show the strongest potential to decline under climate change.
Decades ago (in 1980s), when only scientists were talking about
climate change, reports of sugar maple decline in rural Ontario since the 1950s
was shown to be caused not just by overcutting (leading to over-exposure) and
over grazing by animals; their decline was also linked to acidic atmospheric
deposition, disease and insect infestation—all resulting from a changing
climate.
 |
| collecting maple sap in the spring |
Scientists Scott Bailey (a geologist/soil scientist), Steve
Horsley (a forest physiologist), Bob Long (a plant pathologist), and Rich
Hallett (an expert in foliar chemistry)—who have been studying sugar maple
decline since 1995—agree that climate change and milder winters contribute to
the insect infestations threatening sugar maples. Historically, native insects
are on a cycle of population growth and decline every 10 – 20 years. “What’s
been happening instead,” Bailey said, “is that species are going away and
coming back every 3-4 years.” Research does show that maples are resilient
if the soil contains adequate nutrition. Sugar maples require a lot of nutrients
in their soil to help them grow, cope with disease, and provide internal
signaling (i.e. when to seal off decay or injury, when to take up water).
Little Rouge
woodland is part of the extensive Rouge Park. Alternatives Journal calls the Rouge Park the largest urban park in
Canada. “Totalling 79.1 square kilometres, Rouge
National Urban Park contains multitudes of wildlife, rivers, flora and fauna,”
writes Andrew
Reeves in his article. Protected areas alone can’t
safeguard all species, “there’s a need for wildlife to have room to roam
through the landscape beyond the boundaries of a park,” said Alison Woodley,
national director of CPAWS’s Parks Program when interviewed by Reeves. “They need
that kind of corridor to move through.” Preserving ecological corridors is
especially vital in southern Ontario, writes Reeves. Once blanketed in
Carolinian forest, southern Ontario retains just 15 percent of the highly
biodiverse Carolinian land it once did. “Fly across southern Ontario today
and the occasional woodlot or tree line along a stream are about
all that remain of the Carolinian ecosystem,” wrote author Chris Wood on the vanishing ecozone for The
Tyee. The scraps of marginal forest remaining are so fragmented and
miniscule they’re almost useless, writes Reeves. It wasn’t until 1984 that
the Rouge Valley was formally recognized as a critical slice of Carolinian
forest. Today, Rouge Park remains, next to Point Pelee National Park, one of
the largest intact Carolinian zones left in Canada.
Standing among the maples
and beeches of the Little Rouge woodland, I felt grateful for this natural
reserve. As I made my way back through the stand of oak, pine and cedar, it
started to snow.
Winter is coming…
Winter is coming…
References:
Brown, L.J., D. Lamhonwah, B.L. Murphy. 2015.
“Projecting a spatial shift of Ontario’s sugar maple habitat in response to
climate change: a GIS approach. Can.
Geogr. 59: 369-381.
Brown, Sarah. 2015. “Global Warming Pushes Maple
Trees, Syrup to the Brink.” National Geographic, Dec. 2, 2015. https://www.nationalgeographic.com/people-and-culture/food/the-plate/2015/12/02/global-warming-pushes-maple-trees-syrup-to-the-brink/
Mathews, Stephen N. and Louis R. Iverson. 2017.
“Managing for delicious ecosystem service under climate change: can United
States sugar maple (Acer saccharum) syrup production be maintained in a warming
climate? Inter.J. Biodiversity Science,
Ecosystem Services & Management, 13 (2): 40-52.
Mclaughlin, D.L., S.N. Linzon, D. E. Dimma, W.D.
McIlveen. 1987. “Sugar Maple Decline in Ontario.” Effects of Atmospheric
Pollutants on Forests, Wetlands and Agricultural Ecosystems. NATO ASI Series
16: 101-116.
Reeves, Andrew. 2016. “Saving the Rouge, Canada’s
Largest Urban Park.” Alternatives Journal, Sept. 28, 2016. https://www.alternativesjournal.ca/community/blogs/summer-reading-series/saving-rouge-canadas-largest-urban-park
TRCA. 2018. “Rouge River Watershed Report Card 2018.”
https://reportcard.trca.ca/wp-content/uploads/2018/03/TRCA_WRC-2018_Rouge_FINAL_new.compressed.pdf
