170 Humewood & 3906 Cadboro Bay Road

woodland trustYesterday evening, I and a few others and the current owner looked at the trees on a lot proposed for subdivision just after the news about the Humewood story broke.  There were a good number of large trees for a lot that’s about .6 acres, but most of them seemed ungainly and distorted. One gorgeous Horse Chestnut sat  in a small meadow of its own,  and looked delighted with the world, but the rest were planted around the perimeter and planted too closely together and were shading one another out now so that branches had fallen and new trunks had started and maple-type  trunk shoots were everyone, even on trees that don’t usually do what large maples and alders do. Somewhat dismaying. Tree turf wars with many victims. And one beautiful tree.

hcestnut tree

Saanich has a program for Heritage Trees and is developing a new policy to increase tree preservation–even as it allows more and more houses and condos to be built. So we looked at which trees would have to be saved under the old bylaw and which additional ones would be saved by the new bylaw.

And it was clear to me that a simple law that said “any Maple with a diameter of over 5 inches has to be saved” was better than nothing, but more or less meaningless in terms of good forestry.

There are many factors that affect the “goodness” of urban trees. One is certainly carbon storage, but there are also others, positive and negative: aesthetics, proportion, shade, screening, privacy, healthiness, blocking of views, nuisances. One person’s beautiful large tree (on the next lot over) may be the owner’s nightmare when all the leaves and chestnuts fall or when the large branch falls on his Smart Car or when the annual care bill by an arborist becomes larger than the annual taxes. Most of these factors are hard to regulate.

This lot had a very large willow which spread over four lots and which, apparently, all four neighbours liked. But another quintet of trees had made one neighbour’s back yard totally useless in terms of views or the ability to grow anything edible except perhaps a few radishes. And the willow itself is so ungainly and distorted that it is unlike anything one would see in nature.

By the terms of the new bylaw most of these trees would need to be preserved for the common good—which would surely lead, over time, to few people wanting to plant any large trees and many longing for the day when their existing trees would sicken and die. Property values for lots like this one would descend and values for lots with a few small “removable” trees would grow.

So a better system is clearly required and logically it needs to be based on some kind of a minimum and some guidelines for  maintenance.

It is reasonable to say that any lot should have a certain amount of greenery and if a municipality wants to encourage homeowners to go beyond that, it needs to do so in a supportive rather than a prescriptive fashion. Just  because your mother planted an arbutus, a chestnut and a Western Maple in the same six foot plot thirty years ago doesn’t mean that those three trees are still healthy or happy and entitled, nay required, to continue their claustrophobic life together until death does them part.

Can Tree Planters Save us? An Ongoing Investigation of Trees and Sequestration

Can household trees save us from the more general ravages of global warming? Not very likely. Not bloody likely may be a more accurate term given the comments following. Emissions are very high now and growing and trees can only do so much. But they can do something.

Measuring carbon stored in trees is tricky. But here’s one researcher’s rules of thumbs, for smaller trees, measured at chest height.

  • Less than 5 cm, stores about 2 kg.
  • Between 5 and 8 cm: between 18 and 15 kg.
  • From 8 to 12 cm: between 24 and 38 kg.


Another way of looking at this is to say that each kg of dried tree contains 1. 65 kg of CO2.

Estimates of how much CO2 a North American generates directly run from 2 metric tonnes up to 10 metric tonnes depending on who is doing the estimating, so let’s take 4 tonnes as a minimum. Average carbon stored by a tree that is at least 15 years old range from 7 to 14 kg of Co2 per year and that is obviously very variable depending on the age, variety and size of the tree.

But whatever the parameters, the disjunction is clear. It takes some two to three hundred trees to recycle the average North American’s direct production of CO2. That’s quite a few trees  for a single house and it assumes there’s only one person is living in the house.

The Woodlands Trust in the UK measures all this  somewhat differently. It states that typical hectare of mature Woodland Trust woods will lock up around 400 tonnes of atmospheric CO2, or 108 tonnes of carbon in a year. Note that their ratio is much higher than the one I quoted above of 1.65 to 1.  http://www.woodlandtrust.org.uk/en/why-woods-matter/woods-carbon/Pages/sequestration-rate.aspx#.UcXdAilrZ1s

CHECK THIS. Their figures need to be checked. 400 tonnes seems low for a lifetime but high for an annual figure. 

Taking it as annual. If a Municipality such as Saanich has 100,000 inhabitants responsible for an average of 4 tonnes of CO2 each per year, then it would need to support/maintain 1,000 hectares of a Woodlands Trust type forest. Since Saanich is over 100 square kilometres in size, it could possibly do this, although about 8% of that is lakes and a very large proportion is suburban sprawl and the population is over 110,000 already. 1 Sq. Kilometer = 100 Hectares. 10 Sq. Kilometers = 1000 Hectares.

If Saanich wants an Eco-friendly tree policy rather than just taking Green Talk it should consider the following.

  • Rather than specifying which sizes and types of trees need to be preserved, Saanich needs a formula which says that the norm for any lot or development is to have 10% covered in trees that are at least 15 years old and can be seen to store at least 400 kg of CO2  per year.
  • This is 10% of one individual’s emissions.
  • If there is more coverage (and thus more storage) the owner gets an annual carbon credit from the Municipality carbon bank.
  • It there is less, then the owner pays into the municipal carbon bank.
  • Each year the municipality produces a report on its own Woodland Trust type forests and contributions made or paid by the residents.


HUMEWOOD via the Globe and Mail. June 21st, 2013.

Katherine Hartley used to spend a lot of time under the sweeping maple tree in her midtown Toronto backyard, practising yoga and praying to her ancestors.

But the giant, unassuming tree she once revered slowly began to frighten her. Worried it would fall as she meditated, Ms. Hartley sought and received a permit from the city and notified her next-door neighbour in June, 2012, that she planned to cut down the maple.

That kicked off a year-long battle between the residents of 168 and 170 Humewood Dr. – one that would be fought loudly in their driveways and in court, culminating in a recent legal decision that stands to reshape the yards of residents across Ontario.

The Ontario Superior Court verdict in May, which went unnoticed by most anyone not involved in Hartley v. Scharper, not only saved the maple but created some of the most stringent and detailed law on tree preservation in Canada. Cutting down a shared tree or chopping at wayward branches without a neighbour’s approval could now be a criminal act, punishable under the provincial Forestry Act.

Many of the province’s tree-protection bylaws may need to be rewritten.

The Hartley v. Scharper ruling redefined the technical question of what constitutes a tree’s trunk, giving neighbours equal ownership over trunks that stray over property lines both above and below ground.

“There are a huge number of boundary disputes and this adds clarity,” said Clayton Ruby, a lawyer who argued for the new rules. “This decision means that a lot less trees will be cut down because it now requires the consent of both neighbours.”

With the base of the tree only three centimetres from her backyard, Hilary Scharper sought to stop Ms. Hartley from cutting down the giant. Learning of her neighbour’s plan, Ms. Scharper sat a statue of St. Francis of Assisi, the patron saint of the environment, beside the maple’s trunk.

“We were stunned,” said her husband, Stephen Scharper. “It’s a perfectly healthy tree.”

Legal documents filed by Ms. Hartley’s lawyer describe the moving of the statue under the tree. The Scharpers also posted a notice to any would-be lumberjacks that the tree’s ownership was in dispute.

Under Toronto’s Private Tree bylaw, owners are entitled to remove sick trees. Presenting a report that the tree was healthy and its removal unnecessary, the Scharpers offered to install a system of cables to secure the maple to the ground. Ms. Hartley rejected the offer.

Because the large tree sprawls over much of the Scharpers’ backyard, Ms. Hartley sued her neighbours to establish her right to cut down the tree and enter their backyard to do so.

On May 17, Justice J. Patrick Moore ruled that a shared tree under the provincial Forestry Act starts from where its roots join the trunk up to where the trunk branches out. Justice Moore dismissed the idea of defining a trunk at ground level alone as “arbitrary.”

The ruling gave the neighbours on Humewood Drive common ownership of the tree under provincial law.

“This could impact 60 per cent of Toronto’s trees,” Ms. Scharper said.

Phillip van Wassenaer, an arborist who examined the tree, in the Hartley v. Scharper case, was supportive of the ruling. “It’s more in line with how trees grow and what nature gives us,” he said.

The maple of Humewood Drive is uneven and knotted at its base. Because of surveying required by the case, the ground around the tree has been excavated and orange surveyors marks have been driven into the bark where the trunk strays into the Scharpers’ yard.

Looking to appeal the ruling, Ms. Hartley declined comment.

“A tree can now become common property simply because it grows too large,” said John Howlett, Ms. Hartley’s lawyer. “At the same time, the rights of a landowner to cut the branches or roots of a neighbour’s tree that cross over the boundary line face new restrictions.”

According to Mr. Howlett, many of Ontario’s municipal tree-protection bylaws might have to be rewritten due to the ruling.

“Maybe good things come out of nasty neighbour disputes,” Ms. Scharper said.

June 22, 2013.

The comments below illustrate some of the complexities of measuring sequestration in trees, and the costs thereof, and the size of the larger problem.


5 thoughts on “170 Humewood & 3906 Cadboro Bay Road

  1. Woodland Trust Statement
    We commissioned an independent research study (summary available on request) to determine how many tonnes of carbon a hectare of woodland locks away.

    Our figures are based on the living trees only, which makes the calculation much simpler and provides a substantial buffer, as woodland soils can contain several time the amount of carbon as is held in the living material.

    Basing the measurements around values derived from the Forestry Commission’s own research, we estimate that a typical hectare of mature Woodland Trust woods will lock up around 400 tonnes of atmospheric CO2, or 108 tonnes of carbon.

    This is an average over time. As individual trees die and decay they release their carbon, but provide a gap in the forest canopy into which new trees can grow. So although the amount of carbon in the woods at any one time might vary, we are confident that it does not drop below our estimated value.

    This is why Woodland Carbon is sold per unit area, rather than per tree.

  2. And here is what they sell. A £25 donation creates 25m² of woodland which will capture and store 1 tonne of carbon dioxide during its lifetime. DURING ITS LIFETIME IS THE KEY. So four tonnes would cost someone 100 pounds per year and the Trust would then add 100 square metres to the existing forest. So their 400 tonnes per hectare is a LIFETIME figure, not an annual figure. So Saanich needs to ADD 1000 hectares a year NOT to just maintain it. So in ten years SAANICH would be ALL forest.
    10,000 square metres in a hectare.
    What one needs to do is create the forest and then harvest wood for furniture and houses so the carbon remains stored and new trees can store new carbon.

    Do you worry about how much CO2 you create? Would you like to do something about it simply? Beautifully? By donating just £25 per tonne of Woodland Carbon you can.

    Tree planting has a positive impact on the removal of carbon from the atmosphere – woodlands provide vital new places to help the UK deal with climate change.

    Use our simple guide to estimate the amount of carbon you create through driving, taking a flight or simply heating your home – then, either set up a direct debit or make a simple donation which will be used directly to plant trees and woodlands.

    A £25 donation creates 25m² of woodland which will capture and store 1 tonne of carbon dioxide during its lifetime.

    Find out more about the Woodland Trust and Woodland Carbon

    Woodland Carbon is independently audited every year. Our carbon projects are managed to the highest standard and are registered to the Government’s new accreditation scheme, the Woodland Carbon Code

    Read more about how businesses can invest in Woodland Carbon business investment

  3. Here’s another verification that Woodland is talking about one-time storage, not per annum. A mature forest can soak up the equivalent of 440 tonnes of atmospheric carbon dioxide per hectare in the 50-100 years it takes to reach maturity – that’s a one-off total – not per year and may take several decades to get there. This is from coolantartic.com

    They use a world figure of 22 tones of carbon dioxide each year and calculate:
    22 billion tonnes divided by 440 tonnes per hectare – is needed

    = 50 Million hectares per annum or 500 000 square kilometres per annum

    …to be planted with forest and held in perpetuity (not cut down or allowed to revert back to atmospheric carbon dioxide).

    This is approximately equivalent to the entire land area of Spain, twice as big as the United Kingdom and bigger than any US state other than Texas (696,621 sq km.) or Alaska (1,717,854 sq. km.) To be forested anew each year and held as such forever.

    Therefore planting trees alone other than on a colossal scale is not going to even allow us to stand still
    – let alone start to reverse the effects of global warming.

    So, plant a Spain ever year, a tree-bare Spain, and leave it to maturity. So in 2013 a Spain. In 2014 another Spain.

    So, on a parallel basis: Start planting now in Saanich and in ten years all the buildings are gone and Saanich is keeping up with its original rate. Of course, now there are no more people so they have met their target–but they have all moved away and can’t move back for another 40 to 90 years!!!!!

  4. Lots of sites fudge these basic facts–because they are in the business of selling peace of mind. A typical one is carbonfootprint in the UK: http://www.carbonfootprint.com/plantingtrees.html

    Their basic equation is as follows: On average, one broad leaf tree will absorb in the region of 1 tonne of carbon dioxide during its full life-time (approximately 100 years).

    What they don’t say, using our fairly low figure of four tons per person, is that to even stay even, the UK (population 60 million) needs to plant 240 million trees each and every year and leave them alone for 100 years.
    Assuming 2400 stems per hectare at year five (plantation style) that is 100,000 hectares a year or ten million hectares over 100 years. If I have the zeros right, that’s 100,000 square kilometres or about 40% of the entire UK land base. Not too likely to happen.

  5. Verifying all these questions of forests and sequestration may become a lifetime task. There is a lot of research, but every one seems to come up with variations–which is probable given the large number of variables–but potentially confusing. The PEW Center on Global Climate Change has done what looks like a serious study on forests and the US (2005). This study stresses costs not forestry methods and concludes:

    When a transparent and accessible econometric technique is employed to estimate the central tendency (or “best-fit”) of costs estimated in these eleven studies, the resulting supply function for forest-based carbon sequestration in the United States is approximately linear up to 500 million tons of carbon per year, at
    which point marginal costs reach approximately $70 per ton.

    A 500 million ton-per-year sequestration program would be very significant, offsetting approximately one-third of annual U.S. carbon emissions. At this level, the estimated costs of carbon sequestration are comparable to typical estimates of the costs of emissions abatement through fuel switching and energy efficiency.

    It has some very good charts and insights on different factors, however, and pays special attention to different ways governments could encourage sequestration rather than just planting new trees.


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