Site Discussions

Dear Mr. Mance,

Two years ago, after being a long-time subscriber to Northern Woodlands, I ended my subscription. Not that your magazine isn’t informative, but it seemed to me you showed the forest/wood industry a somewhat biased favoritism when environmental issues were raised. Perhaps I have drawn the wrong conclusions.

The fact that you are now revisiting the carbon-neutral issue with regard to burning wood gives me some hope that your magazine might deal with it in an unbiased, scientific manner.

Allow me to start by suggesting that your use of several terms/arguments reinforced the notion of a possible bias.

“Again” in the title seems a bit condescending to those for whom this is a very important issue. While we homeowners don’t want to give up burning a few cords of firewood each year (something I do), many of us are concerned that the CO2 levels produced by burning wood chips to generate heat or electricity are enormous. In 2013, the EPA identified the McNeil generating plant in Burlington, VT as the hands-down largest GHG polluter in the state: 355,000 plus metric tons of CO2 per year - up to 30 cords per hour.

Note what Bill McKibben has to say about burning trees to generate electricity:

https://grist.org/climate-energy/burning-trees-for-electricity-is-a-bad-idea/

Another term you use, “provocateur” as applied to Andrew Friedland, I find very unfair. It implies that he wants to raise the negatives regarding burning wood just to get people stirred up. The only problem with what he says is that he has muddied the waters by bringing in the carbon-in-the-soil factor. Even without this possible additional problem, the rationale for not burning biomass in large facilities stands on its own. Personally, I would like Dr. Friedland to take a tougher stand than he does.

Finally, I’m dismayed by your using the statement about loggers and suggesting their need to make a living as a key reason to continue with harvesting large volumes of firewood. Of course there are economic implications in reducing the production levels of wood, but is this relevant to the environmental issue? I think not, anymore than arguing that we should not limit coal mining because it hurts the miners.

In the interest of not complicating the discussion, allow me to deal only with cutting trees for large-scale production of wood chips to burn in thermal or electric facilities.  In doing so, I am not drawing any conclusions regarding the well-to-tank analysis of various fuels.

Some hopefully undisputed data (EPA): burning biomass produces approximately 206 lbs of CO2 per million BTU’s and far more (620 lbs per mm BTU’s UK data) for wood chips with 50% moisture – common is Britain. Natural gas produces 120 lbs per mm BTU’s but possibly 200 lbs per mm BTU’s if you count the effects of leaked methane.

Secondly, one of your readers states that young trees sequester at a higher rate than old-growth trees. This flies in the face of a good deal of recent research. Prof. Bill Keeton at UVM has done extensive studies on this topic and has concluded that the way to maximize carbon sequestration is to “nudge forests toward old- growth conditions.”

https://esajournals.onlinelibrary.wiley.com/doi/full/10.1002/ecs2.1721

Contrary to the claims made by one of your contributors, no one is saying that replanted trees don’t start out sequestering carbon. They do indeed. But if you draw a simple graph to compare the rate of resequestration by these replacement trees vs. leaving in place the ones that were cut, it’s easy to see that the total carbon taken up by the later is much higher over the 30 to 60 yrs. under consideration.

While burning biomass may be carbon neutral if you pick the right definition, i.e. that the cut tree eventually fully regrows (if planted), that doesn’t mean that more carbon would have been sequestered if you hadn’t cut the tree in the first place.

We need to carefully assess the science in all this and avoid anecdotal evidence.

Finally, trees are one of the few things nature provides to resequester carbon. We should fully understand the results of cutting them down and using them as fuel.

The following environmental groups have rejected the notion that burning biomass is carbon-neutral in any meaningful way:

Center for Biological Diversity
Chesapeake Climate Action Network
Clean Air Task Force
Dogwood Alliance
Earthjustice
Environmental Working Group
Friends of the Earth
Global Alliance for Incinerator Alternatives
Greenpeace
Partnership for Policy Integrity
Rainforest Action Network
Sierra Club
Southern Environmental Law Center
350 .org
Audubon

plus over 80 scientists in many institutions who signed a letter to the EU deploring use of biomass from US forests to fuel Europe’s energy needs. The lead signer was E.O. Wilson at Harvard.

Plus bringing deer ticks to your area…

I’ve been a guide for 50 years and have watched land companies cut every deer yard in northern Maine! This has forced remaining deer population into the town of Allagash foraging for food. Had the people not started to feed them the herd would no longer exist in northern Maine.

Perhaps in other parts of the world, Marvin, where they’ve been introduced. But they’re native here.

If you think that feeding deer is going to stop than you’re wrong law or not!! First of all the clear cutting has to stop!! And the spraying must stop also!! Deer need woods to live in and don’t need to be eating poison food!! Until this stops I will feed deer until I am dead law or not.

When I was raising goats in central MA, I found that they would browse on conifers when there was snow cover. I read that conifers is a natural preventative to parasites infection. I believe that this is also true of deer (I love the deer sketch).

Great info, I really wanted to know about tapping early, because I actually already collected over 60 gallons of sap when we had the January thaw just this year 2019.

I have been torn about pulling all the taps because the sap ran strong for a week and then it has been cold ever since.  I have not pulled my taps, I guess I will see what happens when it starts again.

Are gray squirrels,indeed, an invasive?

According to my mammal book, they’re two different species, Dana. The greys are Sciurus carolinensis, and as of 1981 there were 5 subspecies recognized. The foxes are S. niger, and as of 1981 there were 10 subspecies recognized.

I’m so heartbroken. In southern California, the houses are surrounded by clear glass wind barriers. I just started feeding birds this winter and many finches and a mourning dove couple eat at my feeders.

The male dove got spooked and flew into the glass and died almost instantly. I’m devastated. I can’t believe my carelessness was responsible for killing one of the mates. Will the female be able to find another mate?

I’m so upset. I love animals so much and I can’t believe I’m responsible for a beautiful dove dying. What could I have done to prevent such a horrible tragedy? The feeders are around 4-5 feet from the glass and the glass is around 4 feet tall. I may stop feeding the birds. I feel so bad.

The article is an eye opener. Initially, and with no background on surveying, my assumption was that to verify an acre, you simply take length x width x conversion factor; irrespective of topography. This was until a real case of subdivision of a family parcel measuring 2.8ha; comprising varying gradients at both ends; and slightly wider at one end; into four equal portions after provision of access roads; a family cemetery and a water well came up.

The argument was how to verify that everyone got an equal sized portion, considering the varying slopes and width of the overall land parcel. It is now clear that whereas everyone will get an equal share of approx 1.63 acres, those in the steeper slopy zone will end up with more surface area…I trust my interpretation. of the text captures the concept.

Is the Grey Squirrel a different species from the equally large but reddish colored Eastern Fox Squirrel or just a subspecies?

It’s hard to say without seeing them, Joe. If the reds are north exposure and the sugars are south exposure, it could be as simple as microclimate. Double check your holes on the reds and be sure you didn’t drill into dead wood. When you say they’re smaller than the sugar maples but big enough to tap, what do you mean exactly? What’s the diameter of the respective species?

We have one just outside of Green Bay Wisconsin! We had a couple of weeks recently with temps well below Zero day and night, yet here it is, three times in the past two weeks. I occasionally toss a little bit of dry cat food under the bird feeder to help it out.

I’ve lived in the same home for 20 years and have always entertained gray squirrels.  Last year we had a red squirrel show up and then the problems started.  As your article suggests; the much smaller red squirrel is the aggressor!  Amazing.  He also feeds at different times than the gray squirrels which I think it must prefer.

Hi,we were just watching these pretty birds this morning around our bird feeder.(its Feb.12/2019)We didn’t see them since summer and started to wonder, where they suddenly came from? So I decided to learn more about them and came to your interesting article. Thank you so much, I am sitting here saying..wow and we will definitely look at these birds differently.

Great article.  I plan to have the boundaries of my residential property surveyed so that I can be sure that a retaining wall that I plan to rebuild is on my property.  How can I be sure that the surveyor was accurate?  Is there some warranty or insurance that comes with a survey?  Thanks.

I have a 45’ tree that leans “almost ” correctly.  If I cut it the way it leans the top 15’ will hit the fence. I need it to land 3’ farther to the right . Should I make a partial back cut and put a wedge in the left side then finish the cut to make it fall to the right?

(Posted for Joe:)

I just tapped red and sugar maple trees at the same time using the same type of tap kit.  They are at different locations.  The sugar maples have produced a few gallons of sap in less than a week yet the red maples have produced nothing.  This is with a few days of early sugaring.  The red maples have less sunlight than the sugar maples and are smaller.  The red maples are big enough to tap.  Why haven’t they produced sap?

I too was struck by some of the statements made by Brave Little State in their program “The Pros and Cons of Heating with Wood”, particularly in their carbon calculations.  Here is some recent research to consider:

At a Mohawk Trail Woodlands Partnership meeting in October, UMass researcher Paul Catanzaro presented results of a study he did with Anthony Amato from UVM on the Impact of Forest Management on Carbon.  By reviewing Forest Cutting permits in Massachusetts, they found that most harvesting here is partial cutting, removing about 4Mbf/acre or about 13 metric tons of carbon/acre, cutting roughly 1/3 of the trees at a time.  A typical harvest reduces the net carbon storage/acre by about 17 percent, 10 metric tons/acre from the harvested timber, and another 3 tons from disturbing the duff.  Below surface carbon appears not to change much if BMPs are followed to protect soils from erosion.  By their calculations, the carbon removed in partial harvesting is replaced by new growth primarily of existing trees in about 9 years (at a rate of 1.5 metric/tons per acre per year).  A shelterwood harvest that cuts 2/3s of the net volume would reduce total stored carbon by about 30 percent and would take about 15 years to replace the stored carbon.

This contrasts sharply with the 60 to 100 year carbon replacement scenario cited in the broadcast.  That scenario seemed to be based on the idea that if you cut down a sizable tree, it will take 60 to 100 years for an equal sized tree to grow to replace it.  While that might be true for an isolated tree in the open, it doesn’t reflect actual forest growth.  With the partial cutting common here, the trees uncut use the increased sunlight to grow faster and replace carbon much faster.  Added growth absorbs more carbon than new trees would initially.

Another carbon study was done recently by Mass Wildlife on clearcuts they did to create early successional habitats for wildlife.  The study reportedly that net carbon on the clearcuts was within 2 percent of the total before harvesting after just 6 years regrowth.  Whoa – how can that be?  I thought. There’s no way the trees could have regrown that fast.

I thought about that last weekend when I skied in a family woodlot where we had a seed tree harvest to regenerate an ice damaged stand 4 years ago.  In the snow, the bare new trees seem pretty small and puny compared to the seed trees that tower above them.  There’s no way those sprouts and saplings can hold anywhere near the volume of carbon as the trees that were cut did, even if there are thousands per acre.  Seems obvious, right?  There might be a lot of carbon in the rotting tops that we haven’t cleaned up that are slowly tuning to duff, but that wouldn’t replace all the wood taken out.

But as I whacked around, I suddenly realized that we often spend too much time looking at the trees and overlook the vegetation.  While the new trees in our woods range from 1 foot to 8 feet tall, the forest floor is densely covered by an nearly impenetrable mass of low woody vegetation: blackberries, raspberries, hobble bush, striped maple, fire cherry, which rises to 6 foot high or more in many areas, way more was there before the harvest. It all stores carbon, not permanently, of course, but for that period until the new trees grow tall enough in 5 or 6 years to close their crowns and shade it out.  As the undergrowth dies back, that carbon will then be released and taken up by the fast growing trees.

So carbon storage in a regrowing forest may initially be more horizontal in the brush layer than vertical in the trees we normally measure it in.  Calculating the carbon just in the new trees doesn’t really show us the whole picture.

That insight got me thinking about another part of the broadcast which talked about concerns about particulate emissions from wood burning.  We all know that wood burning, while much more environmentally sustainable than burning fossil fuels, can produce high levels of Pm25 emissions which can pose health issues.  Whenever anyone reloads their stove or furnace, they produce considerable smoke until the combustion gets going. Why, anyone can see that wood burning seems to produce more emissions that fossil fuels.

Or does it?  Some information from an recent study about wood pellet boiler emissions by the UMass Department of Environmental Health Sciences might make you start to rethink that assumption.  Using a state grant, EHS Professor Rick Peltier and his students equipped a van with emissions monitoring equipment and took it around to gather weeks of emissions data at six locations downwind from modern pellet boiler installations.  Because wood burning emissions differ chemically from those from fossil fuels, they could measure which emissions came from pellets and which from nearby fossil fuel systems .

The first finding from their research was that all the pellet boiler installations have very low Pm25 emissions, in most cases much lower than the EPA limits. This shouldn’t be a surprise as the pellet boilers are specifically engineered to burn cleanly with low emissions.  What was surprising, on the other hand, was their finding that the pellet Pm25 emissions were often much less than the Pm25 emissions from neighboring oil-fired systems.  In one example where a pellet boiler heated part of a town building complex and oil boilers heated the rest, the Pm25 oil emissions were so high that a simple way to improve air quality might be to just switch the other buildings over to pellet heat.

It turns out that just because we don’t see obvious smoke when fossil fuel systems fire, that doesn’t mean that they are burning cleanly, particularly as those systems age.  Conversely, while emissions are more visible with wood heating systems,  a lot of what we see may be steam, not particulates.  In the case described in the broadcast where Goddard College installed a central wood-fired heating plant and distribution system to replace 20 oil-fired boilers in individual buildings, the particulate emissions from the modern wood system may turn out to be less than the less visible emissions from the 20 old oil-fired units.