[who_would_fardels_bear]

I understand the trees that grow fast tend to be less dense and more porous. I could imagine a similar phenomenon in all plants. The CO2 allows them to grow faster and so there is less time for them to take up minerals, i.e. less mineral dense.

[Blueflag]

There’s some there, there, but go back to times earth’s history when C02 was was order of magnitude higher and terrestrial plant growth was dense and robust.