The Cortical Chlorenchyma Collaboration Gradient Dominates the Shoot Economics Space in Larix principis-rupprechtii

Plant economics is based on carbon and nutrients rather than money. While leaf strategies aboveground are well characterized along an economic spectrum from "fast-growing and short-lived" to "slow and conservative," economic models defined by aboveground shoot strategies remain unclear. Here, we offer a comprehensive view of aboveground economics and show that collaboration between shoots and stem cortical chlorenchyma can break out of the one-dimensional economic spectrum, offering a full range of economic possibilities. Trait data from 1551 current-year shoots of a single species confirm the classical fast-slow "conservation" gradient but reveal that most variation is explained by an orthogonal "cooperation" gradient, ranging from self-reliant resource acquisition to outsourced nutrient synthesis via the stem cortical chlorenchyma. This expanded "shoot economics space" provides a solid foundation for predicting aboveground responses to environmental change.