Data from "TransfertN" project: Plant biomass, forage quality and residue composition in alfalfa-fescue mixtures

The dataset is composed of shoot and root biomass measurements and biochemical analyzes (C and N elemental analyses; delta13C, delta15N isotopic analyses) conducted on each species in a six-year field experiment comparing alfalfa-tall fescue mixtures with corresponding alfalfa and tall fescue pures stands.