They say you’re an adult when you stop growing up and start growing out. Trees do both, investing in primary growth, height, and secondary growth, diameter. Effort put into growing up means there are fewer resources for growing out, so how do trees allocate resources for growth?

Franceschini et al. explored the trade-off between primary and secondary growth by considering simultaneously the allometric exponents relating height to diameter at breast height (γh,dbh) and stem volume to diameter at breast height (αv,dbh) obtained from an 8893 stem analysis across North-Eastern America. They give evidence that the species growth strategies differed between conifers and broadleaves with respect to the mode of development. These results have important implications for quantifying future carbon stocks in managed forests.