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If you’re interested in low-carbon landscapes and green cities, I can’t recommend enough getting a coffee and watching this lecture by Elaine Oneil and George Berghorn in the @MSU_Forestry Forest Carbon and Climate programme. canr.msu.edu/news/fcwg-2018… [Thread] 
After 20 years of management, conifers will have sequestered around 40t C/ha, but unmanaged natural regeneration less than 5. After 25 years managed conifers will have sequestered 80t/ha and natural regeneration less than 10.
The best option for carbon capture in the forest is to manage it but not harvest it: the top black line is managed but not harvested; the gold line is natural regeneration.
But this raises the question of how to pay for it, because for most forests it is the timber sales which give them their long-term economic stability and ensure their existence.
The efficient carbon-capturing power of improved conifer crops didn’t happen by accident. This shows how rate of carbon capture has increased 13x from wild natural forests.
In one stand of forestry the carbon rushes up and down as trees grow and are harvested; but in the whole forest it is a flat line. If the sawmill has a sustainable supply, the carbon stock must be stable.
When US public forests took the decision to harvest less, total carbon (in forest and harvest) began to decline. After a few decades it began to decline in the forest itself.
And it’s important to remember that it’s not all about the forest: the harvested timber does not simply evaporate, but goes on to play a central role in a low carbon economy.
A building made from timber is a carbon store. A building made from mass timber (CLT) is a massive carbon store.
Even more importantly, it avoids the carbon emissions caused by building with concrete or steel. Net zero carbon emissions is in the centre of this graph.
The International Building Council has been reviewing its code for 2021, which is used by most municipalities in the US. This is likely to result in a lot more buildings using mass timber instead of reinforced concrete and steel: good news for US timber growers.
What would be the carbon benefit of turning the lumber in a typical old house being demolished, into CLT? 80% can be re-used; saving about 6t carbon/house; and in Michigan there are 225,946 abandoned old houses – enough for over 500 large CLT buildings.
That’s Michigan; how does it compare to the UK? All these graphs about carbon capture and storage in the forest, natural regeneration, silvicultural improvements and carbon in buildings apply. confor.org.uk/news/latest-ne…
What also applies are the difficult decisions about tradeoffs: biodiversity can have a carbon cost. Forest management runs up a bill which someone must pay for. The supply of timber into the market enables or hampers a low carbon economy. There's no One Right Answer.
Our challenge is that with less than 15% forest cover and patchy planting cycle over only one century, the UK doesn't yet have a ‘complete’ forest resource to research and demonstrate. forestresearch.gov.uk/tools-and-reso…
This is why it’s so important for us in the UK to look beyond our borders, to help our own timberlands grow as quickly as possible into a serious force against the climate emergency. confor.org.uk/news/climate-c…
If these snippets have intrigued you, please do watch the @MSU_Forestry lecture, which explores all these issues in much more depth - the rest of the series is good too! canr.msu.edu/news/fcwg-2018…
