Forest Island

The property neighbouring ours doesn’t have a house on it. It is agricultural land used for growing corn and soybeans, with the exception of one odd little patch of forest. The few acres of trees form a little island in the midst of a sea of corn. The soybean crop has been harvested, but the corn is still standing.

A drainage system underlies the land and empties into a rather impressive ditch that borders the fields, eventually emptying into our little river. The water level in the river can change dramatically in heavy rain, no doubt in part due to the artificially accelerated rate of drainage of water from the soil. I took a walk along the ditch to take a look at the forest island, now that the soybeans have been harvested and a path along the edge of the field is clear.

It is composed mostly of impressive Red Pines (Pinus resinosa). They may have formed part of a plantation at one time, but if so, the straight-row pattern that is usually easy to see wasn’t evident. It seems strange that this one little patch of trees, a few acres worth, has been left untouched. I would like to think that they were saved for their majestic beauty, but it seems more likely that plans to harvest the timber will follow at some time in the future. Although the pines predominate, there is also a sprinkling of small maples and beech, now leafless. Around the edge of the forest fragment is a narrow ribbon of birch trees.

CORRECTION: Thanks to Tony for letting me know that the trees are actually Scots Pines (Pinus sylvestris)! They were planted about 35 years ago as a Christmas Tree plantation, but never harvested. As the trees were planted close together in anticipation of a harvest in 6 to 8 years, they grew to be rather spindly when they exceeded their “best before” date as Christmas trees. A number fell over and were otherwise lost, so the remaining stand represents the survivors. They appear to be doing very well.

If I had paid more attention to the cache of cones I came across, I might have done a better job of identifying these trees. Scots Pines are popular as Christmas trees because of their shape and good needle retention, while their fast growth habit and good response to shaping makes them popular with growers. They were one of the first tree species to be introduced to North America. John Laird Farrar notes in Trees in Canada that in Europe the Scots Pine is a tall, straight tree with wood of excellent quality. In North America, the trunks are seldom straight (although I would have to say most of the trees in this stand were pretty straight) and the wood quality is poor owing to the seed source chosen by early settlers. The trees can live in the range of 150 to 300 years, so this stand is still young.

Up until a couple of hundred years ago, most of eastern North America was covered in forest. Now, in eastern Ontario, in the Ottawa region, forest cover is only 13 percent in some areas, and the remaining forest is highly fragmented, a few acres here, a few acres there.

Fragments are not good habitat for birds. Forest fragmentation increases nest predation by a stunning list of predators. Skunks, opossums, and raccoons hunt at night. Snakes, chipmunks, even deer, are not averse to a tasty egg when the opportunity arises. Other birds such as blue jays and crows will rob nests of eggs and nestlings. Cats take a huge toll on the bird population. Cowbirds lay their eggs in the nests of other birds and their larger chicks often survive at the expense of the host’s own young. Predation is higher in forest fragments than in continuous forest. One study found in suburban woodlots, about 70% of nests suffer predation. In rural woodlots, it’s about 50%. Other studies have found different rates, but all found that nests in fragments suffer more predation than nests in continuous forest cover.

Fragments are population sinks. That is, more birds are killed over the breeding season than are replaced by new youngsters, resulting in a net loss to the population. The birds that nest in fragments are like a steady trickle of water going down the drain. Large forests are usually population sources because breeding success is relatively high. For example, the Great Smoky Mountains National Park, the largest national park in the eastern United States, has more than 200,000 hectares of continuous forest. Some 10,000 nesting pairs of wood thrush produce a surplus of almost three thousand females each year beyond the number required to replace the breeding females who have died.

Fragmentation of habitat is one of the reasons the songbird population is crashing. To read more about fragmentation and other songbird issues, check out Dr. Bridget Stutchbury’s book Silence of the Songbirds.

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Birches

I was recently driving down a road that bisects the Larose Forest. The birches above reminded me of Robert Frost’s poem, Birches.
It begins:

When I see birches bend to left and right
Across the lines of straighter darker trees,
I like to think some boy’s been swinging them.

Along with The Road Not Taken and Stopping by the Woods on a Snowing Evening and a few others, Birches is one of Frost’s most beloved poems. When I googled birches and Frost, I got a long list of results. You can readily find copies of the poem, comments on the poem, free essays on the poem. In the latter category, I was drawn to an essay that states “When we first read the poem, all I could think of was how the poem just wasted 10 minutes of my life.” Well, maybe you get what you pay for! The poem continues:

But swinging doesn’t bend them down to stay.
Ice-storms do that. Often you must have seen them
Loaded with ice a sunny winter morning
After a rain. They click upon themselves
As the breeze rises, and turn many-colored
As the stir cracks and crazes their enamel.
Soon the sun’s warmth makes them shed crystal shells
Shattering and avalanching on the snow-crust–
Such heaps of broken glass to sweep away
You’d think the inner dome of heaven had fallen.
They are dragged to the withered bracken by the load,
And they seem not to break; though once they are bowed
So low for long, they never right themselves:
You may see their trunks arching in the woods
Years afterwards, trailing their leaves on the ground
Like girls on hands and knees that throw their hair
Before them over their heads to dry in the sun.
But I was going to say when Truth broke in
With all her matter-of-fact about the ice-storm
(Now am I free to be poetical?)

It’s true that ice storms can be hard on trees, especially birches. I think in the case of the birches pictured, however, another possible culprit is edge effect, the susceptibility that comes with fragmenting a larger forest with roads, utility corridors, or other development. Ontario Nature has a great introduction to fragmentation in our forests available here. Frost continues:

I should prefer to have some boy bend them
As he went out and in to fetch the cows–
Some boy too far from town to learn baseball,
Whose only play was what he found himself,
Summer or winter, and could play alone.
One by one he subdued his father’s trees
By riding them down over and over again
Until he took the stiffness out of them,
And not one but hung limp, not one was left
For him to conquer. He learned all there was
To learn about not launching out too soon
And so not carrying the tree away
Clear to the ground. He always kept his poise
To the top branches, climbing carefully
With the same pains you use to fill a cup
Up to the brim, and even above the brim.
Then he flung outward, feet first, with a swish,
Kicking his way down through the air to the ground.

Where would such a boy be found there days? A swinger of birches. While even a generation ago children were sent outdoors by their frazzled mothers (“What are you doing inside on such a nice day? Get outside and play!”), todays children spend much of their time watching TV, playing video games, working on computers, text-messaging. When they are outdoors, it is often to participate in an adult-organized sport such as soccer. In his book Last Child in the Woods, author Richard Louv coined a term for this disengagement with the outdoors: Nature-deficit Disorder. Now there is a growing movement to reintroduce children to the natural world. An example is the No Child Left Inside program. Another take on this is Robert Bateman’s Get to Know program. Frost finishes:

So was I once myself a swinger of birches.
And so I dream of going back to be.
It’s when I’m weary of considerations,
And life is too much like a pathless wood
Where your face burns and tickles with the cobwebs
Broken across it, and one eye is weeping
From a twig’s having lashed across it open.
I’d like to get away from earth awhile
And then come back to it and begin over.
May no fate willfully misunderstand me
And half grant what I wish and snatch me away
Not to return. Earth’s the right place for love:
I don’t know where it’s likely to go better.
I’d like to go by climbing a birch tree,
And climb black branches up a snow-white trunk
Toward heaven, till the tree could bear no more,
But dipped its top and set me down again.
That would be good both going and coming back.
One could do worse than be a swinger of birches.

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