Biomass Production and Environmental Considerations from Reed Canarygrass Fertilized with Organic Residues in Northern Environments

CORE IDEAS: Liquid swine manure and municipal biosolid provide sufficient N for reed canarygrass.Liquid swine manure and municipal biosolid use do not cause nitrate leaching and heavy metal accumulation.Kura clover with reed canarygrass improves DM yield but less than fertilizers. Sustainable biomass production on marginal lands of northern areas using cool‐season perennial grasses and under‐exploited N sources requires development. We determined the biomass production of reed canarygrass (Phalaris arundinacea L.) fertilized with municipal biosolid (MB), liquid swine manure (LSM), mineral fertilizer (M), or grown with a legume species and harvested either in July or October along with the consequences of soil contamination by nitrates and heavy metals. The experiment, conducted at two sites from 2009 to 2011, included three target N rates (40, 80, and 120 kg total N ha⁻¹) applied in spring as either MB, LSM, or M along with an unfertilized control treatment and a treatment with kura clover (Trifolium ambiguum M. B.). Reed canarygrass responded positively to N application from all sources. Both sources of organic fertilization resulted in DM yield close to that obtained with mineral fertilization but seasonal DM yield was greater with LSM than with MB. Kura clover improved DM yield compared with reed canarygrass without N fertilization, but it was not sufficient to reach DM yields obtained with N fertilization. The three N sources did not affect residual soil nitrates in the fall at both sites, the soil solution nitrate concentrations measured during the growing season at one site, nor the soil accumulation of heavy metals (Cu, Zn, and Cd) in the fall of the last year at both sites. Our results confirm that, as an alternative to M use, MB and LSM are valuable N sources for reed canarygrass biomass in northern areas.