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AskPablo: How many trees does my office Kill?

| Monday October 8th, 2007 | 17 Comments

trees.jpgThis week I was asked by Craig how many trees his office kills each year. In order to give him an answer I had him collect some basic information, like how many reams of paper they use each week. His office uses around 60 reams per week, an average of 100 sheets per person and 30,000 sheets in total (a ream holds 500 sheets). Over a year the office would use 3000 reams, or 1,500,000 sheets! But how many trees gave their lives to make it possible for old people to print every e-mail they get? Well, let’s find out…


First I need to figure out how big the average tree is. The answer to this question depends highly on how big/old the trees used are. If you raid a Christmas tree farm to make your paper, the answer would be in the millions and if you go into an old-growth redwood forest the answer would be quite small. Does this mean that we should cut down only big trees? No, on the contrary. Younger trees grow much faster, and therefore sequester more carbon from the air. They also grow more densely and it is probably better to support a monoculture tree farm than it would be to raze a biodiverse old-growth ecosystem.
In 2001 the US timber industry harvested 46.6 billion board-feet (one board foot is 12″ x 12″ x 1″, or 144″ cubic inches), which is equivalent to 110 million m^3. At a density of 520 kg/m^3 (for douglas fir) this amounts to an annual harvest of 57.2 million metric tons. Globally 42% of industrial wood harvest devoted to paper production. If this statistic holds true for the US timber industry (does it really matter in a global market?) we are harvesting 24 million metric tons of trees for paper production each year. According to one estimate, the average tree weighs 680 kg, or 0.68 tons. So this means that an estimated 16.32 million trees are harvested for paper production in the US each year.
One of my favorite sources for lifecycle factors are the data sheets that accompany the Wuppertal Institute’s MIPS manual. According to this resource about 2.56 tons of biotic material (trees) are required to make a ton of virgin paper. This is because some parts of the tree are unuseable for paper making, like the branches and bark. If all of my assumptions are correct the US would produce 9.375 million tons of paper each year.
Back to the office paper… A ream of Craig’s paper weighs 3 pounds (1.4 kg). At the lifecycle factor of 2.56 mentioned above, each ream would require 3.6 kg of wood. And at 3000 reams per year his office is using 10,752 kg of wood. Based on the average tree weight above, this amounts to 16 trees per year, or about one every three weeks.
I am happy to report that after I did all these calculations Craig found out that is office recently switched to Aspen 100, a 100% post-consumer recycled content product from Boise Cascade. So the real result of my analysis is that Craig’s office is saving 16 trees per year by using recycled paper. On top of that they have a great recycling program to give their used paper a new life in someone else’s office. Maybe even yours…
With some basic numbers from your procurement person you can use my assumptions above to calculate you own office’s deforestation contribution. This makes a great argument for switching to 100% post-consumer recycled paper in your office too!
Pablo Paster
Sustainability Engineer
www.AskPablo.org
For some great paper-related facts see: http://www.coopamerica.org/programs/woodwise/consumers/stats/index.cfm
and: http://www.afandpa.org/Content/NavigationMenu/Pulp_and_Paper/Fun_Facts/Fun_Facts.htm
10/8, 10:40am: It was pointed out to me that my assumption about the weight of a ream was incorrect. I have adjusted the numbers. Thank you Dave.


▼▼▼      17 Comments     ▼▼▼

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  • http://www.sustainplan.com J√∏rgen

    In addition to the 16 trees saved, Craig’s office also saves a bunch of energy. The Ecological Footprint of creating virgin paper is split about 50/50 between what goes into the paper and the process energy required to make the paper. Creating recycled paper takes only around 40% of the energy needed for creating virgin paper.

  • Jessie

    This was such a help. I will try to recycle as much paper as i can. Thanks again for informing me that i use so much paper.

  • Jessie

    This was such a help. I will try to recycle as much paper as i can. Thanks again for informing me that i use so much paper.

  • Jerry W O’Neal

    Don’t we have more trees today then a 100 years ago, don’t the paper companies re-plant back more then they cut down, have you a better way to clean yourself after going to the toilet? And is it a scientific fact we are harming the earth or causing global warming? has not this happen at least 5 times that we know of? thanks…Jerry

  • Tale Beppset

    Jerry –
    1) On the east coast of the US there may be more trees than 100 years ago. However, what paper companies replant is generally of dismal ecological richness compared to what we removed. This is why cutting the last of our old growth forests is such a bad idea. Also, tropical forests are disappearing at an alarming rate and we definitely have a lot less of those than 100 years ago.
    2) Toilet paper can be made out of sustainably harvested tree farms, it’s also not a major contributor to deforestation so no big deal there
    3) Harming the planet? No, the planet will be fine. We are seriously harming most ecosystems, however, at our peril. And yes, global warming is part of it, this time very much caused by us!

  • Ron

    Where does toilet paper go after it is flushed? Does it not go to sewage treatment plants? Then does it not create sludge that has to be removed from the tanks and disposed of which in turn creates further environmental damage? So, you cannot say that toilet paper is not harming the planet or are my facts incorrect?

  • Mike

    Instead of killing trees why dont we grow hemp? An acre of hemp can produce 4 times the amount of paper that an acre of trees can. Plus the hemp can be replanted the next year for another run. With trees you have to wait 10 years or so.
    If these slimey politicians would allow us to grow a plant that God put here for us to use, we wouldnt have to worry about trees.

  • naquay

    i think that cutting down trees is bringing down forests and i think if everybody recycled we would have more trees and a beautiful community. so everyone please recycle.

  • naquay

    i think that cutting down trees is bringing down forests and i think if everybody recycled we would have more trees and a beautiful community. so everyone please recycle.

  • John Koudela

    This reply to how many trees are used fails to recognize that for all those trees taken, all of them are replanted. Paper sources are renewable – thus technically there isn’t any truly gone trees. I used to work for Weyerhaeuser – one of the largest paper companies.

  • http://www.vyouz.com Melanie Hetfield

    Just the information I was looking for. We are about to relase our quartely eZine GreenVyouz and have 1200 members ready to accept our unique online magazine. I was wondering how many trees it would take if our eZine was in paper form. I’m so glad that it’s not. If in paper form we would use up 288 reams of paper for one issue.
    To get your copy go to http://www.greenvyouz.com/
    The more people we encourage to live an Eco Life, the better off our planet will be.

  • http://www.vyouz.com Melanie Hetfield

    Just the information I was looking for. We are about to relase our quartely eZine GreenVyouz and have 1200 members ready to accept our unique online magazine. I was wondering how many trees it would take if our eZine was in paper form. I’m so glad that it’s not. If in paper form we would use up 288 reams of paper for one issue.
    To get your copy go to http://www.greenvyouz.com/
    The more people we encourage to live an Eco Life, the better off our planet will be.

  • Stephanie

    I live in a small rural community, and have my whole life. As a child, there were several Christmas tree farms covering hundreds of acres. With the popularity of fake trees, it did not save those real trees. Instead, two of the large farms are now residential developments with almost NO trees. My only concern is that by using ALL post-consumer paper, managed tree farms for paper will go the way of Christmas tree farms, and the number of overall trees on the planet will again decline.

  • http://www.lanwalker.com Alain Vezina

    Hi Everyone
    I’m a software developer here in Canada. I wake up this morning and I had the same question “How many trees do I kill each year?”
    To answer that I start to write an desktop application that hocked up to the my printer. Each time, I print, my new application cumulate statistic on my paper use. It alert me on my killing performance. I hope to install my app other desktop in my office.
    Maybe that will help to reduce our paper use
    Alain

  • Patricia Teel

    This is garbage. Paper is made from the scraps of trees that have been cut down to make boards for building homes, other buildings, furniture, for clearing land for the homes or clearing land for agriculture. Old growth forests are NOT cut down to make paper. If you want to save trees, don’t have any children.

  • http://www.unisourcegreen.com/pdf/TruthinPaper.pdf JH

    While all your intentions are certainly benevolent, I believe some of your fears about paper usage are irrational and misinformed. Example:

    “i think that cutting down trees is bringing down forests and i think if everybody recycled we would have more trees and a beautiful community. so everyone please recycle.”
    » naquay at April 16, 2008 9:39 AM

    Intuition and feeling have never proven to trump science. While this person is clearly concerned about the sustainability and beauty of the planet, emotional judgments rarely accurately predict how the world works. Use of EMPIRICAL evidence is the only way one could make such a seemingly definitive conclusion about actions such as deforestation.

    Just because trees are being “killed” in the manufacturing of paper doesn’t mean that the ecosystem, environment, or well-being of the earth is being destroyed. To understand how using trees for materials affects our world you must analyze the net effect of their usage, not the immediate effect of there being less trees.

    Responding to some comments from above;

    “what paper companies replant is generally of dismal ecological richness compared to what we removed.”
    » Tale Beppset at February 2, 2008 11:25 AM

    How are the trees that paper companies replant of “dismal ecological richness” compared to that of existing plantlife? Are human-planted trees less ecologically superior than those naturally planted by nature? I do not see the logic in this statement, however as I am not an ecologist or dendrologist, I would appreciate being corrected if I am wrong.

    Also,

    “…tropical forests are disappearing at an alarming rate and we definitely have a lot less of those than 100 years ago.”
    » Tale Beppset at February 2, 2008 11:25 AM

    The paper we use is NOT made from the trees of tropical rainforests; thus
    I hardly see how the the fact of tropical deforestation is relevant as to why we should use less paper.

    Do not use irrelevant facts and emotional arguments to sway people into believing a point. If an argument is true, then facts and statistics relating to it will clearly show it as such.

    Please read this article to shed some light on paper myths and facts:
    http://www.unisourcegreen.com/pdf/TruthinPaper.pdf

    Hope I have positively contributed to this conversation!

    -JH

  • http://www.aschoolofquiet.com Quiet

    Dear JH,

    You know as well as the next man that science is often used to destroy the myths needed to attain a higher ideal. There is a lot of truth in your claims but they sound more like an excuse to me. I read today: everybody wants to change the world, but nobody wants to change. You are avoiding responsibility by getting stuck in the details and narrowing the context of the matter.

    This example of your best demonstrates my point: “quote:How are the trees that paper companies replant of “dismal ecological richness” compared to that of existing plantlife? ” Are you serious? A forest is more than a collection of trees.

    Trees may grow back in a certain amount of time, but for a forest ecosystem to restore itself, much more time is needed.

    We could go on for days, months or longer about petty details but I would rather spend my time considering actual changes in my consumption to rule out more of my ecological impact. Humans are the largest polluters. So: yes, we need the myths.

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