[Robotbeat]

That’s not true. Methane is a significantly more potent greenhouse gas than CO2, so if the tree is absorbing CO2 but the decomposing needles and leaves are emitting methane, it could easily be a net GHG emitter.

[garmaine]

Trees don’t produce CH4 (except in decomposition).

[benj111]

"but the decomposing needles and leaves are emitting methane"

[garmaine]

Ah, true. I hadn’t thought of droppings off the tree. (Comment was edited I think, or I seriously lack reading comprehension.)