Table 1: Species used in the experiment. FF represents the functional form types derived by Levang-Brilz and Biondini  based on the morphological and physiological characteristics listed in this table. β and are scaling constants that relate root biomass (RB (g)) to root lateral spread (RLS (m) = ) and root surface area (RSA (m2) = ), while τ is a scaling constant for root plasticity ( no plasticity) derived by Biondini  using data from Johnson and Biondini . R : S is the root-to-shoot ratio; RGR is relative growth rate (gg−1d−1); NUE and PUE are N and P use efficiency (g·gN−1 and g·gP−1, resp.); Imax-N and Imax-P are the maximum N or P uptake rate per unit of root surface area (g·m−2·d−1). Nomenclature follows the PLANTS Database (http://plants.usda.gov/), National Plant Data Center, Baton Rouge, La, USA.