Harvesting Fertilized Rye Cover Crop: Simulated Revenue, Net Energy, and Drainage Nitrogen Loss

Abstract

Harvesting fertilized rye (Secale cereale L.) cover crop has been suggested as a method to increase producer revenue and biofuel feedstock production, but drainage N loss impacts are currently unknown. Using the tested Root Zone Water Quality Model (RZWQM) across several N rates, spring application of 120 kg N ha -1 prior to winter rye harvest reduced drainage N loss by 54% compared with no cover crop and by 18% compared with planted rye that was neither fertilized nor harvested. Estimates of producer revenue and net energy were also positive, with 8.3 Mg ha -1 of harvested rye biomass. If confirmed by field studies, these results suggest that double-cropping fertilized rye is a promising strategy to increase producer revenue, increase net energy production, and reduce drainage N loss. Core Ideas• Fertilizing winter rye increased estimated revenue and harvestable biomass.• Fertilizing winter rye increased net energy production.• Harvesting fertilized winter rye reduced simulated drainage N loss.• Rye revenue in response to fertilizer rate plateaued at approximately 120 kg N ha −1 .• Field studies are needed to evaluate fertilized/ harvested rye cover crop.Abbreviations: CC, cover crop; CCH, unfertilized harvested cover crop; CCH_L_x, late harvest of fertilized cover crop; DM, dry matter; NCC, no cover crop.

Drainage N Loads Under Climate Change with Winter Rye Cover Crop in a Northern Mississippi River Basin Corn-Soybean Rotation

“…The average corn harvest date was 13-September, and ranged from 30-August to 13-October. Winter rye was planted three to six days after simulated maturity of corn and soybean under baseline weather for all scenarios to mimic over-seeding of rye into standing crops [29,60]. All corn, soybean, and rye were planted and harvested or terminated on the same date for all scenarios: baseline climate, projected climate change, and with and without winter rye.…”

Soil health assessments: how and why?

“…Due to the well‐documented roles that SOC has in aggregate formation, soil structure, aeration, and water and nutrient cycling, researchers continue to investigate and validate several carbon‐related indicators. Current soil health assessments are focusing on several available soil carbon indicators such as permanganate‐oxidizable carbon (Hurisso et al, 2016), beta‐glucosidase (Stott et al, 2010), particulate organic matter (Cambardella and Elliott, 1992), and microbial biomass carbon (Rice et al, 1996).…”

Does harvesting cover crops eliminate the benefits of cover crops? Insights after three years

“…Interest is growing in the multi‐functionality of cover crops (CCs) to enhance soil ecosystem services such as C sequestration, improvement in water quality, soil fertility, and productivity, among others. An additional ecosystem service from CCs could be providing biomass as feed for livestock (Blanco‐Canqui et al., 2020; Ketterings et al., 2015; Sulc & Franzluebbers, 2014) or feedstock for cellulosic biofuel production (Blanco‐Canqui et al., 2020; Feyereisen, Camargo, Baxter, Baker, & Richard, 2013), while improving farm economics (Malone et al., 2018). Currently, crop residues are baled for supporting livestock and biofuel production, but literature indicates that excessive crop residue harvesting can negatively affect soil properties (Stewart et al., 2019).…”

“…(2020) discussed that harvesting CCs to a cutting height above 7.5 cm for expanded uses such as livestock and biofuel production does not, in general, have an adverse effect on soil properties and subsequent crop yields compared with non‐harvested CCs, although literature on harvesting CC is limited. The limited literature indicates that harvesting CCs can improve farm economics without eliminating the soil benefits of CCs (Holman et al., 2018; Malone et al., 2018). However, more data from different cropping systems, CC species, CC management scenarios, soil types, and climates are necessary to fully understand how harvesting CCs affects soils and subsequent crops.…”