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enough is enough: Ireland is NOT planting trees to combat climate change @HuffPost. 70% of trees planted will be non-native commercial conifers destined for clearfell. they threaten wildlife and will not reduce atmospheric carbon in the long run (thread)
huffpost.com/entry/ireland-…
huffpost.com/entry/ireland-…
Sitka spruce from the pacific NW is the main forestry tree in Ireland. it is densely planted and usually harvested after 40 years. i've done some carbon calculations to test lobbyist claims that new spruce plantations will act as carbon sinks... 
...Sitka spruce are planted on marginal agricultural land, which often means species rich meadows. these can be home to rare and declining species, like the marsh fritillary butterfly. these meadows store a lot of carbon in their soils...
...a lot of this soil carbon is broken down and released when a new spruce plantation is created. this study found that 230 tonnes of soil carbon per hectare were lost over the course of a plantation lifespan (40 years) citeseerx.ist.psu.edu/viewdoc/downlo…
this is offset by the carbon that the spruce trees themselves absorb: 860 tonnes per hectare over 40 years (assuming 2m spacing, no thinning and yield class 20, worked out from WCC carbon lookup tables 2018 woodlandcarboncode.org.uk/standard-and-g…
however, when clearfelled a lot of this carbon is lost - possibly 45% based on US studies. this is because brash, stumps and roots are left behind, and when these rot down they release their carbon back into the atmosphere google.co.uk/amp/s/news.mon…
more carbon is lost during manufacturing processes (25% based on US studies), and so of the 860 tonnes absorbed, only 260 tonnes remains stored in wood products. take away the 230 tonnes lost from the soil and you're left with only 30 tonnes/hectare...
...this is very likely not enough to cover carbon produced during planting and logging operations, and lost quickly from some types of wood product.
to reiterate, Ireland planting trees has nothing to do with combatting climate change: its yet more greenwashing by the Irish government. @HuffPost please consider amending your article so that it doesn't spread disinformation.
planting trees (or better yet allowing them to plant themselves) can help to reduce atmospheric carbon and restore our wildlife, but only when its the right trees in the right places with the right management. more of pic 1, not pic 2!
