Environment Q&A Archive

When trees are taken, what is lost from the forest?

Hi, Nice site. I recently bought a house whose source of heat is a wood burning stove. I've really gotten to enjoy using it and I was very interested in your environmental reasoning for using wood vs. fossil fuels.

I looked all over you site and read the All About Smoke section, but have not been able to find an answer to this question:  What is the chemical constituency of wood? I understand that there is carbon, oxygen and hydrogen, but what I am looking for is all the materials that make up wood so I can differentiate which substances are burned off (smoke) and which ones stay in the fireplace (ash). I am very curious for reasons of sustainability. When wood is taken from a forest, a certain amount of minerals are taken with it. As a tree grows it stores carbon from the atmosphere, but also "pulls" minerals/substances/chemicals from the soil that also are stored in the wood. When one takes a tree away from its native habitat, one is also taking these substances away. The carbon will get cycled back into the atmosphere, but the other substances have been removed permanently. I would like to know what all those substances are, both the ones in the ash, and the ones that may also go up the chimney with the smoke.
Thanks, Mike

Hi Mike,
Yes, you are quite right that when trees are taken for fuelwood something is lost from the site.  You are also right that the main loss is in the form of minerals.  However, keep in mind that in the entire life cycle of the tree, the part taken is only certain fraction of the total contribution to the site of that tree.  Each year deciduous trees deposit a fair mass of leaves on the forest floor.  Over a 50 year period that is a big contribution to the mineral and biomass stock of the soils.  When it is harvested, we take only the bulky solid wood, not the entire tree.  Also, in most of North America about half (it is hard to estimate) of the firewood produced is a byproduct of other forestry operations that produce saw logs or pulp.

As we point out up front, whatever energy source you use will have impacts.  I can only say that I've seen wood lots that have been harvested selectively for firewood for generations and they look terrific.  My assessment is that a healthy, well managed forest can tolerate a moderate loss of biomass each year without any decline in viability.

To get a more scientific answer you would have to ask a forest ecologist, of which there are very few.
John

Wood burning is bad for your health?

I went to one of the links and there was a whole nine pages of why woodstoves are bad for you and the environment. In particular, it talked about the toxins and carcinogens that wood burning lets off.  It seems we have to decide to either burn a hole in our lungs or burn a hole in our pockets.??? 
Tracy in Toronto

Hi Tracy,

We link to Burning Issues as much for comic relief as for factual commentary.  Pick any single environmental issue and you'll find at least one organization run by fanatics.  Burning Issues is run by folks who are, for whatever reason, fanatical about wood smoke.  From our point of view, it is better to have opponents who are so intemperate, so radical, so uncompromising as to be dismissed by reasonable people as fringe loonies.  That's why we are happy to link to Burning Issues.

Please don't misunderstand me, we don't consider wood smoke good to breathe.  Clearly, it is not healthy for you.  But neither is diesel truck and bus exhaust or car exhaust or many other pollutants.  This is from the Union of Concerned Scientists:

"The average truck on the road today spews 22 grams of smog-forming pollution and nearly one gram of soot every mile."  See:

http://www.ucsusa.org/transportation/brf_bigdiesel.html

That is about 60 g/h of particulate matter at highway speed.  My EPA certified wood stove emits an average of 3 g/h of particulate matter per hour of operation.  So what should have priority, my home heating or a truck taking computer games to Wal-Mart?  I don't like to justify wood burning emissions just by saying the other guy is worse, but we must put all pollution into proper perspective and reduce it all.  At woodheat.org, we don't suggest that everyone in Toronto should start heating with wood, quite the opposite.  We think wood is appropriate as a regionally specific energy resource.

So, I don't think the options are "to either burn a whole in our lungs or burn a whole in our pockets".  Responsible people can reduce their personal pollution and also reduce cost by choosing good equipment and practicing energy conservation.  The fact is we'll all be practicing energy conservation fairly soon whether we like it or not.  See:

http://www.gulland.ca/depletion/depletion.htm

Finally, in light of Burning Issues warnings of immanent disease and death from wood smoke, consider this: The human species lived with its collective head in a cloud of wood smoke for its entire million year history on earth, until the last 150 years.  If the periodic exposure to the smell of wood smoke were anything like as toxic and dangerous as the fanatics would like you to believe, we never would have got this far.

Regards,
John

Misleading Statement?

In searching for material  on wood burning stoves, I  came across your web site.  I find that it has a good  deal of useful information,  however, there is a very  misleading statement that  is made on the homepage.  It is given below.   

"But when it is used  effectively, wood is a  fine fuel compared to the  fossil fuels like oil, gas  and coal, whose consumption  leads to global warming."   

I will not get into the debate  of does carbon dioxide cause  global warming, because I think  the answer is not really known.  However, to make the assertion  that burning wood is better than  burning oil, gas, or coal because  of global warming is absurd. Wood  like these other fuels is a  hydro-carbon. If it is burned  completely and perfectly, its byproducts, water and carbon  dioxide, are the same as what is  produced from burning coal, oil,  or gas.   The statement on your home page  should be modified to reflect  the facts. It will also lead credibility to your site.   

John  

Hi John, 
We find your message very interesting, not least because we gather you are with Sandia Labs.  You are not just a curious nonspecialist who might be unfamiliar with the carbon cycle as it relates to atmospheric CO2 and biomass growth, decay and combustion. See:
http://www.woodheat.org/carbon.htm 
http://www.woodheat.org/forest.htm 
(or simply type 'carbon cycle' into any search engine)  

We don't spend time debating the greenhouse gas/global warming/climate change issue because more than sufficient information is available now to take action.  We note that those who persist in denying any connection are usually paid to do so, directly or indirectly, and therefore lack credibility.  

We stand by the quoted statement on our site – it is not misleading.  We think it is misleading to suggest that, in the area of energy use and the environment, business as usual is the desirable strategy.  You are just going to have to live with the fact that we disagree with you. 

Regards, 
John

Wood smoke the most deadly outdoor pollution in Canada  

Your biased little piece on wood burning (All about wood smoke) is crap. Just talk to anyone with asthma who lives within a block of a wood burner. During inversion conditions, which is almost every night (Manitoba) if the smoke from our neighbour is in our yard, then it is infiltrating our house. The smoke comes in through our fresh air intake. Then we are subjected to severe health problems - inflammation of the nose, throat and lungs, cough, and aggravated asthma symptoms. One night exposure is almost enough to hospitalize 2 people in our home.  Have you heard of Bill C-32? The government will try to get the chemical companies to stop producing the 10 or 12 most lethal chemicals known to man which includes dioxin. Wood smoke contains dioxin along with other lethal compounds and because of the size of the particulate matter (PM10 or smaller) it infiltrates any homes within blocks of a wood burner. Over the years almost all trees (wood) have absorbed dioxin. There is no safe wood to burn anymore.  What you say about how to burn is partially true but let's be realistic. At $229.00 /cord nobody burns wood properly. They burn garbage, wood scraps from construction sites, pallets and anything else that doesn't cost money. Wood burners do not burn properly. They smolder their fires (it's called "banking") to save money. In my town they burn in the spring and fall when the temperature is about 10 - 15 degrees C. There are no thermostats to turn down the temperature so they cut off the air. They smolder their fires all day and all night from September to May. It's disgusting. It stinks. It is dangerous and "illegal'. It is a "private nuisance", an "odour nuisance" and it causes illegal "trespass".  Wood burning out in the country (more than a mile from a populated area) might be okay but should be totally banned in a populated area. If the wood burners had double burning stoves with catalytic converters and they burned only properly seasoned wood and they burned properly and if they didn't burn when inversion conditions existed and if there was an enforcement officer to oversee that these mini-incinerators were being operated properly then there would be less of a problem with the pollution.  I guess that means it will never happen.  Courts have already ordered the abatement of wood burning on the basis of "private nuisance". I may be forced to take that route also.  I realize that you probably are a conscientious and knowledgeable (except in environmental illness) wood burner, but the majority are backwards uneducated people who have never heard of environment, environmental illness, dioxin, PM10 and carcinogen.  Tell both sides next time. Talk to someone who is sensitive to wood smoke and who lives next to a wood burner.  It is a killer. I know because it is killing me.

Burned but still breathing (with the help of puffers) 
Arni   

Arni,
I am sorry to hear about your problems with the irresponsible wood heat activities of your neighbour.  We at woodheat do not condone or support anyone's use of wood fuel if it interferes with another person's enjoyment of their home and property. We think the main fault lies with government, which neither supports people in the responsible use of wood fuel, nor helps people like you to stop the smoke in their community.  Our view generally is that visible smoke is not acceptable, except perhaps for a few minutes at startup.  In the future we hope to be more effective in helping people to achieve their wood heat objectives, while limiting air pollution.  I can tell from the tone of your note that your mind is made up and you don't want to hear about the positive aspects of woodburning relative to the other energy sources. I hold somewhat similar views about the wasteful use of gas, oil and coal which is destroying everyone's environment. My colleagues and I are supporters of responsible residential wood heating.  We are neither evil nor stupid.  If given the opportunity, we would like to help your neighbour to clean up his/her act. 
John   

Arni responds:
John,  Thanks for your response.

I do have an attitude when it comes to wood burning and I apologize for it. You are 100% correct as far as the fault lying with the government. There are laws and regulations in place, but the environment officers do not even have a basic knowledge about the subject. I also agree with you concerning the use of oil and coal.  There would not be a problem if the burners restricted their burning to the winter only and if they didn't smolder their fires overnight. At one point last winter our yard was in smoke for 96 consecutive hours and the temperature outside hovered around 0C and warmer.  It takes about 2 hours from the time that the wood smoke is blown onto our yard before it's effects are felt inside our house. It doesn't smell like smoke but rather like sawdust (sweet and spicy) and it burns my nose and throat very severely.  I have changed my heating system (gas) and installed an electronic air cleaner (which helps a bit) but somehow we have to prevent the woodsmoke from getting in through our fresh air intake. Do you have any suggestions?  Are there any air cleaners or filters that can do the job? If not I may have to move. Is there any type of air quality monitoring equipment?  As for re-educating the local burners there is no chance of that. $'s take precedent over life which also seems to be Manitoba Environment's position. So I might have to hit them where it hurts in the pocket book then I might get some results but no sympathy.  Again I apologize and I hope that you educate the wood burners, the people who sell the stoves and the government about responsible woodburning. 
Arni  

A challenge to wood as a renewable resource

While I agree that wood heat alternatives might be better in the short term than fossil fuel dependency, the world is also in deforestation crises, and by encouraging wood use, you are fostering this depletion – another imbalance to our ecology.  We need to find an alternative energy source that truly is "alternative" and does not rely on "endangered" resources.
Sincerely,
Roberta 

Roberta,
Only a fool would suggest that wood is the right fuel for all regions and all situations (as the fossil fuel promoters do for oil and gas). You can dismiss us as irresponsible if you wish, but I think we promote the moderate, sustainable use of wood as a fuel.  I am guessing that you don't fully understand the concept of renewability (see this page).

It is naive to think that 'science' will surprise us with a new energy source that will solve all our problems. The solution lies in using a lot less energy of all types and using more regionally specific and appropriate fuels. But then, I suspect you have your mind made up.
Regards,
John

Roberta responds:

John, 
Thank you for responding so promptly and so intelligently! Your "suspicion" is correct in that I haven't fully explored your concept of renewable as far as wood burning is concerned – and yes, I agree, it's naive for us to think that "science" will save us and our Mother Earth. I'm just recently reading Thom Hartmann's book, "The Last Days of Ancient Sun" and am blown away by how serious our situation is – and am deeply concerned as to how we can "wake people up" to become more responsible and change the "burn and conquer" mentality and history we've inherited. When I was "surfing the net" and marking sites for future reading, yours just happened to have an email response for me to complain to. No, I haven't gotten my mind made up – I'm just concerned and exploring.

Again, thanks for your response – and good luck!
Roberta