Does planting Trees actually deliver carbon capture

[egbert]

A paper released last year (don't have the reference to hand) found typical modern forestry planting techniques lead to significant release of stored carbon when used in grassland sites, such that it takes over 20 years for the trees to make up for it.

It looks increasingly like the evidence shows planting trees to replace established pasture is a serious mistake in climate terms.

Disagree. In decades terms, it's a no brainer, providing you plant species likely to grow usable timber, and use it in such a way as to hang onto the carbon.
Longer term? all buildings/structures/timber artefacts rot in the end -just as carbon in soils is not buried and safe for ever.

Pile drive sitka trunks into the ocean floor.......jobs a good'un

 

[holwellcourtfarm]

Disagree. In decades terms, it's a no brainer, providing you plant species likely to grow usable timber, and use it in such a way as to hang onto the carbon.
Longer term? all buildings/structures/timber artefacts rot in the end -just as carbon in soils is not buried and safe for ever.

Pile drive sitka trunks into the ocean floor.......jobs a good'un

Well managed diverse permanent pasture has repeatedly been measured to hold similar carbon content to typical established boreal forest. In that case what benefit is there in converting land from one to the other (apart from subsidy payment to do it)?

Planting diverse mixed woodland in carbon depleted land is, I agree, potentially helpful. For long term grassland it's as effective and much quicker to promote better grassland management to achieve carbon sequestration.

 

[Exfarmer]

There have been many studies over the years and very little evidence of carbon capture by trees.
However the general public has this impression that a large oak tree can hold many tonnes of carbon. So by planting a tree will guarantee locking this up for generations. This ignores the fact that up to 99% of those trees will be removed by thinning to leave 4 trees from the original 400 planted per acre In the case of oak. I strongly suspect that the sequestration will be barely enough to cover the planting.

 

[Derrick Hughes]

Depends on many variables. Apart from the fuel burnt to do the job the biggest is probably the existing soil carbon level. Much land that's ploughed every year doesn't actually have much carbon left in it to release!

This is not adding up when its estimated that grassland holds around 20% of the world's carbon

 

[DaveGrohl]

[QUOTE="egbert, post: 7307613, member: 9965]

Pile drive sitka trunks into the ocean floor.......jobs a good'un
[/QUOTE]
How does this work then? Genuine question. Pile drive them into the sand? Will they not rot down there and release the carbon back up to the surface in time? Use fossil fuels to harvest, transport and pile drive? Pile drive them into the bedrock? Even more fossil fuels used? Might as well do it on land then. As I say, I'm not having a go at you, I just want hear the reality about what happens to this wood. To be fair, at least you've had a go at an answer.

I'm just getting so worn down by the whole tree planting nonsense. It really is the ultimate in lipstick on a pig while the human race continues regardless.

 

[Derrick Hughes]

Planting trees to burn them seems crazy

 

[wanton dwarf]

Woodlands do not need to be anaerobic to capture carbon. Yes vegetation rots but it is in symbiosis with fungal, yeast, worm, mammal, avian, insect, reptilian, etc production along with retention in timber. A wood is an ecosystem not a collection of trees. Even row cropped softwoods contribute to a capturing system that extends beyond yield class evaluation of timber gains. Further more calculations based on yield class growth take no account of leaf drop, fruit production, branch casting through shading etc during the life of the tree and make no consideration of lop and top remaining on the site at felling.
If a deer that would not previously inhabit an area is born and raised in a developing woodland it is capturing carbon, if a worm eats a leaf it is capturing carbon, likewise every bacteria, microbe and animal that belongs to that system.
I know my p.p builds soil because rocks visible 15 years ago are now covered with soil, but, my deciduous trees have one heck of a natural mulch below them. I wouldn't like to bet on which is the better performing system without a great deal of site specific research and evaluation.

Leave any area alone and soil will be deposited by the wind and rain (from deserts). Soil deposition occurs everywhere and it's why Roman buildings are now under metres of soil.

 

[wanton dwarf]

Depends on many variables. Apart from the fuel burnt to do the job the biggest is probably the existing soil carbon level. Much land that's ploughed every year doesn't actually have much carbon left in it to release!

A bit one dimensional. The crop which is grown on the "Depleted Carbon" soil takes Carbon from the air not the soil to grow - whereas a Carbon rich soil the reverse will happen to a greater extent. Also there is no reason why the farmer ploughing does not use Brown Bin Compost or Biosolids to enhance their soils and those soils will benefit to a greater extent than already Carbon rich soils.

 

[Exfarmer]

A bit one dimensional. The crop which is grown on the "Depleted Carbon" soil takes Carbon from the air not the soil to grow - whereas a Carbon rich soil the reverse will happen to a greater extent. Also there is no reason why the farmer ploughing does not use Brown Bin Compost or Biosolids to enhance their soils and those soils will benefit to a greater extent than already Carbon rich soils.

Sorry crops of any sort, do not normally extract carbon from the soil. Photosynthesis takes carbon dioxide from the air and moisture from the soil to generate glucose and oxygen, which is released back into the air.

 

[holwellcourtfarm]

Planting trees to burn them seems crazy

It's probably better than burning fossil fuels but it doesn't REVERSE climate warming, just limits the increase a bit. This is probably the biggest error in the whole biomass drive.

As Professor Dave Frame (Victoria University Climate School, NZ) and Professor Myles Allen (Oxford Martin Climate School) both repeat: unless we stop emitting fossil carbon everything else is just moving deckchairs on the Titanic (my interpretation not a direct quote).

 

[egbert]

Pile drive sitka trunks into the ocean floor.......jobs a good'un
[/QUOTE]
How does this work then? Genuine question. Pile drive them into the sand? Will they not rot down there and release the carbon back up to the surface in time? Use fossil fuels to harvest, transport and pile drive? Pile drive them into the bedrock? Even more fossil fuels used? Might as well do it on land then. As I say, I'm not having a go at you, I just want hear the reality about what happens to this wood. To be fair, at least you've had a go at an answer.

I'm just getting so worn down by the whole tree planting nonsense. It really is the ultimate in lipstick on a pig while the human race continues regardless.
[/QUOTE]


It's the best long term carbon capture/storage involving trees (in upland UK) that I can envisage.
Driven into the sea bed, they're effectively in anaerobic environs, and will sit there for-easily- centuries.
It's true that we're currently burning fuel to do it, but that'll change soon enough...mebbe.
Several tonnes per hectare per year, potentially secured.

The best bit is considering where all this carbon was being held these last 300 million years!!!!!

I'm right with you with the fatigue.
A very broadminded forestry professor i'm in touch with, numbers of forestry pro's, and lil old me, are all dumbfounded by the blind assumption that it's the answer.
But like rewilding et al, I now see it as a greenwash concience salve, for those that know in their hearts what the real problem is.

 

[DrWazzock]

Millions of years ago the level of carbon dioxide in the air was 10 times higher than it is now and it still managed an ice age. They say though that solar radiation was lower. But evolution, and life carried on.
They reckon now, that with the suns output being higher, the Earth is much more sensitive to small rises in greenhouse gases.

I don’t think trees will really make much difference to be honest. They might tie up a bit of carbon short term but they are as nothing compared to the amount of fossil carbon released over the last 200 years.
If you are serious about reducing carbon dioxide levels in the atmosphere then you really need nuclear powered machines to turn it back into solid stable carbon like graphite or even synthetically produced fossil fuel then store it somewhere. There will be vast quantities to store: the whole thing would be hugely expensive and consume yet more resources.
And as we can’t really predict the level of heat arriving from the sun it might anyway be counterproductive. One day we might be glad of the green house effect if it holds off an ice age.
There is a hell of a lot more to it than just planting trees, though generally I’d agree that more vegetation of all kinds and less bare earth and desert can only be a good thing as is conservation of fossil fuels and more use of renewables and nuclear.

 

[renewablejohn]

Planting trees to burn them seems crazy

Why. Its a very sustainable way of life. Grow the tree then use it to keep you warm in winter then put the wood ash back on your veg patch to improve next years veggie's. Even better if the wood is from the prunings of apple and plum trees.

 

[DrWazzock]

Go into a wood a scrape the rotting leaves away from the soil. You will find the rotting layer isn’t actually that deep before you hit mineral soil. That layer is oxidising as fast as it’s being added to do it it isn’t a long term carbon store. The timber is storing carbon but usually ends up oxidised somewhere down the line either through natural decay or burning. So no, not a lot of long term sequestration. Very little in fact.

 

[egbert]

Go into a wood a scrape the rotting leaves away from the soil. You will find the rotting layer isn’t actually that deep before you hit mineral soil. That layer is oxidising as fast as it’s being added to do it it isn’t a long term carbon store. The timber is storing carbon but usually ends up oxidised somewhere down the line either through natural decay or burning. So no, not a lot of long term sequestration. Very little in fact.

As I've said oft...I try to find evidence of it being otherwise...and cannot.

I snuffled about one of British Columbia's acclaimed cedar forests a couple of years ago. 10,000+ years of growth? And the boulders still poke through the surface.
Tropical far North Queensland? Same deal, only with more snakes.
Local ancient oak forest - supposedly untouched by human hand, although uz peasants know better- and the mosses cling to the granite amongst which the trees grow.
Where is all the carbon, once you've built up a working stock?

 

[DrWazzock]

We might be better to try to work out how we can green the deserts to help at least stabilise the climate and live with the inevitable temperature rise. Desalination plants and irrigation plants should be going up left right and centre. Make the most of the higher temps and CO2 levels and harness them. We are really just pissing about here in the Uk. We need to in the Sahara forcing it into retreat with stabilisation. But instead of that they are cutting one another’s throats over religious hocus pocus.
Can you really buck global “evolution” with any kind of “civilisation”. Could if the will was there but just at the hoo haa there is when people can’t burn lots of fuel for Christmas.
Pfffffft.

 

[holwellcourtfarm]

As I've said oft...I try to find evidence of it being otherwise...and cannot.

I snuffled about one of British Columbia's acclaimed cedar forests a couple of years ago. 10,000+ years of growth? And the boulders still poke through the surface.
Tropical far North Queensland? Same deal, only with more snakes.
Local ancient oak forest - supposedly untouched by human hand, although uz peasants know better- and the mosses cling to the granite amongst which the trees grow.
Where is all the carbon, once you've built up a working stock?

And yet some farmers are managing to build 1 to 2cm of soil a year without importing biomass to do it just by applying the right management. The 6 foot deep prarie soils were created by the plant/herbivore complex over millennia and destroyed in 50 years by the plough and rowcrops.

 

[egbert]

And yet some farmers are managing to build 1 to 2cm of soil a year without importing biomass to do it just by applying the right management. The 6 foot deep prarie soils were created by the plant/herbivore complex overt millennia and destroyed in 50 years by the plough and rowcrops.

The UK generally has very different conditions to the prairies. They're frozen for months at a time, and have much lower rainfall.
When they do naturally erode, it's feet at a time.
And just as you point out, as soon as you start scritching them about, it starts going down again.

As for being able to build 1/2" of soil a year here...go on, imagine you could do it for 100 years. Would that be 4' of stable, safely worked ground?
Not round here it wouldn't.
It's be so soft you could get near it, and on rainy weeks, the stock would sink to their bellies.
Building OM into your soil, in a mixed farm scenario, can only ever be a good thing. But pretending it can be done forever isn't any more realistic than pretending planting a few saplings will reverse climate change.

 

[DrWazzock]

And yet some farmers are managing to build 1 to 2cm of soil a year without importing biomass to do it just by applying the right management. The 6 foot deep prarie soils were created by the plant/herbivore complex overt millennia and destroyed in 50 years by the plough and rowcrops.

Agreed. Non oxidative farming helps a little bit . It will attain a higher equilibrium of stored carbon but even in the bottom of an undisturbed wood the stored carbon in the litter reaches a certain level then as much disappears annually as is added, otherwise the trees would be 30 foot deep in leaf litter by now.
Carbon Conservation agriculture is a good thing on many levels. Less fossil fuel usage, more carbon sequestration but still using vast amounts of fossil fuel not least in manufactured fertiliser.
Lots and lots we can do to help with an open mind but 200 years of fossil fuel burning isn’t going be reversed very quickly at all. We haven’t even stopped adding to the problem yet.
Which brings me into the thought that while people are still burning jet fuel to go on pee ups in benedorm then my efforts are insignificant.

 

[farmerm]

Disagree. In decades terms, it's a no brainer, providing you plant species likely to grow usable timber, and use it in such a way as to hang onto the carbon.
Longer term? all buildings/structures/timber artefacts rot in the end -just as carbon in soils is not buried and safe for ever.

Pile drive sitka trunks into the ocean floor.......jobs a good'un

Imagine the amount of fossil fuel you burn transporting and pile driving sitka trunks into the ocean floor.... and a large shipment of timber carries far less carbon than a oil tanker of a similar displacement. The quantity of fossilised carbon that we extract and release each year is mind blowing.