permaculture

[<scott@permaculture.org>]

Thanks Ossi for re injecting a little gravitas into this conversation - 
Welcome!!


>  -------Original Message-------
>  From: ossi@kulma.net
>  To: permaculture <permaculture@lists.ibiblio.org>
>  Subject: Re: [permaculture] Earthships
>  Sent: Jul 31 '16 05:16
>  
>  Hi Toby et al.
>  
>  Sorry to tell you, but it seems like you have not explored this issue
>  enough and I suggest you are wrong with the proposed assumption
>  regarding carbon storage in trees.   Such growth pattern you describe as
>  universal would apply only on trees grown in cleared open areas, f.e.
>  after a clearcut or as if timber is left in seed-tree positions after
>  harvest.   Now if we compare to old growth forests this "universality"
>  does not apply.  As an example I have found more than 100 year old
>  spruces grown from total darkness of dense undergrowth so that they are
>  only apx. 15 cm in diameter but when dead seem to be more durable in use
>  than most of the metals I know about.  That kind of wood is heavy even
>  if is totally dry.  In any of the (semi)natural boreal forests I've seen
>  that "universal" pattern you describe doesn't apply unless it disturbed
>  strongly by human intervention, which equals to collapse in amount of
>  stored carbon.
>  
>  Rate of growth is very simple thing but big growth rings do not relate
>  to with how much carbon is stored in the tree.  You can have 3 times
>  fatter tree grown in 15 years, but when you  cut that tree down and dry
>  it - it can be lifted with single hand as there is not really carbon
>  stored in their cells, but rather empty space between relatively fragile
>  cell walls and their fresh weight was due to enormous amount of water
>  that was there.  Due to large cell structures that kind of fast grown
>  wood doesn't really have any other use than to shade ground for natural
>  forest to regenerate with accumulated density, which stores the carbon
>  for longest periods available.
>  
>  In contemporary Finland current construction wood sales are providing
>  mostly too low quality wood, so that they need to make composite
>  elements out of the wood-material available and therefore it is becoming
>  rare to find single timber being publicly sold as construction wood - as
>  they do not have much of such timber available due to unsustainable
>  forest  management which was widely adopted since the 2nd world war.  
>  I'd think that old trees that grow slowly have just achieved their
>  adulthood and would likely store at least 1000 times more carbon both in
>  dry weight and durability in time than any fast grown crap from the pulp
>  plantations.
>  
>  So what comes to the forest management practice you describe, yes that
>  is useful in terms of fast supply for timber (which can be stored in
>  buildings for 500 years as you say), but do not relate that to optimal
>  carbon storage of trees as their capacity under such management is not
>  even nearly the optimum that can be achieved.  Also in terms of ecology
>  leaving the oldest trees growing should also apply especially if
>  permaculture principles are seriously taken under consideration.  I
>  strongly suggest that maths regarding such issues should follow logic
>  like this: more density, more carbon there will be stored and more
>  durable that carbon is within extended periods of time.  Of course there
>  is somewhere a point where the growth rate could be too little and cells
>  get fragile due to that, but generally in GOOD quality trees one likely
>  cannot read the growth rings without magnification as they are far less
>  than 0,5 mm.
>  
>  Second thing that I would like to mention is that when trees "rot" in
>  forest they do not release all their carbon as CO2 into atmosphere as
>  under such conditions any CO2 released would be heavier than air and
>  therefore unless being technologically shot up into the sky would float
>  under forest canopy and would be most of the year captured directly at
>  least by conifers or their lichen partners.   Also a lot of carbon that
>  was in decomposed wood especially in case of the old growth forest would
>  be circulated by fungi within the system and be either stored in soil or
>  in community of living beings.
>  
>  Now, please keep up the good work you're doing.
>  Thank you for you are and kind wishes for all sentient beings.
>  
>  Ossi Kakko
>  (Eastern Fennoscandia)
>  
>  
>  
>  
>  Toby Hemenway wrote  2016-07-28 06:51:
>  > Scott’s comments are excellent. I would add that the rate at which a
>  > tree sequesters carbon is also dependent on where the other trees are
>  > . Nearly all species of trees slow their growth rate enormously once
>  > the canopy closes as they compete with other trees for light and
>  > nutrients. I’ve looked at tree rings on many species of both hardwoods
>  > and softwoods, and the pattern is universal: fast growth (fat growth
>  > rings) for the first 20-60 years, then only slow growth after that.
>  > They store most of their carbon in youth.
>  >
>  > Solution would be to selectively log when the canopy closes to open up
>  > light gaps so the other trees can keep growing fast. Then cut those
>  > when they slow down, and plant new trees in the gaps. Put it all in
>  > structures that last 500 years.
>  
>  >> On Jul 27, 2016, at 5:53 PM, scott@permaculture.org wrote:
>  >>
>  >> In the case of fast maturing trees that are harvested at maturity
>  >> would be excellent building materials.  But trees that are still
>  >> growing should be allowed to continue to sequester carbon.
>  >>
>  >>> -------Original Message-------
>  >>> From: Scott Vlaun <scott@moosepondarts.com>
>  >>> To: permaculture <permaculture@lists.ibiblio.org>
>  >>> Subject: Re: [permaculture] Earthships
>  >>> Sent: Jul 27 '16 15:39
>  >>>
>  >>> To Georg's point, sequestering carbon in well built structures made
>  >>> from wood harvested sustainably. Here in Maine there are short lived,
>  >>> fast growing species like balsam and poplar that make decent building
>  >>> materials and would otherwise die and quickly release carbon as they
>  >>> rot in the forest.
>  >>>
>  >>> Scott Vlaun
>  >>> Center for an Ecology-Based Economy 207 520 0575
>  >>>
>  >>>> On Jul 27, 2016, at 5:33 PM, Scott Vlaun <scott@moosepondarts.com>
>  >>>> wrote
>  >>>>
>  >>>> My mother in law lives in a 25 year old earthship in NM. I've spent
>  >>>> a lot of time in it and it is pretty fantastic. Can and bottle walls
>  >>>> eliminate a lot of carbon intensive concrete as do massive Adobe
>  >>>> thermal mass walls. The sculptural aspects, especially tile mosaic
>  >>>> make for a very Inspired living space. Embodied energy per sq. ft.
>  >>>> on these structures is extremely low and even in northern NM she
>  >>>> gets by on less than. Cord of wood per year, only needed when cold
>  >>>> and cloudy. I'm extremely sensitive to tire outgassing and have
>  >>>> never even gotten a whit. Labor intensive to be sure though!
>  >>>>
>  >>>> To
>  >>>>
>  >>>> Scott Vlaun
>  >>>> Center for an Ecology-Based Economy 207 520 0575
>  >>>>
>  >>>>> On Jul 27, 2016, at 5:07 PM, Georg Parlow <g.parlow@gmx.at> wrote:
>  >>>>>
>  >>>>> Thanks Lawrence and Scott for this dialogue. Valuable.
>  >>>>>
>  >>>>> However, one question, Scott:
>  >>>>>
>  >>>>>
>  >>>>>> **Whenever possible eliminate using forest products in
>  >>>>>> construction.  The wood is much better used as a carbon sink.
>  >>>>>
>  >>>>> To my understanding wood IS a carbon sink - and if it sits in my
>  >>>>> house for 200+ years this is just as fine as sitting (and maybe
>  >>>>> falling over and rotting) in the forest. What is it I do not see?
>  >>>>>
>  >>>>> Georg
>  >>>>>
>  >
>  permaculture mailing list
>  permaculture@lists.ibiblio.org
>  subscribe/unsubscribe|user config|list info:
>  http://lists.ibiblio.org/mailman/listinfo/permaculture
>