Intensification of dryland cropping systems for bio-feedstock production: Evaluation of agronomic and economic benefits of Camelina sativa

Abstract

Camelina (Camelina sativa L. Crantz) is a promising bioenergy crop, but a sustainable production system for this crop has not yet been well developed. There is also concern about competing land use between crop productions for bioenergy or food use. One approach to overcoming this concern and developing sustainable production systems for bioenergy crops is potentially replacing the fallow period in wheat-based cropping systems with bioenergy crops. The agronomic and economic benefits of growing camelina in rotation with winter wheat were evaluated in a replicated rotation study from 2008 to 2011 in the Northern Great Plains (NGP), focusing on the effects on wheat yield and overall profitability of the cropping system. Average winter wheat yields were 2401 and 1858kgha−1 following camelina and barley, respectively, representing a 13.2 and 32.8% winter wheat yield reduction compared to the fallow–winter wheat rotation (2766kgha−1). Lower winter wheat yield in the alternative systems were offset by 907kgha−1 camelina and 1779kgha−1 barley yields. Economic analyses revealed that at existing market prices and production costs, the traditional fallow–winter wheat rotation provides greater net returns to growers due to substantially lower variable costs of the system. Scenario analyses that use more optimized, lower cost camelina production practices show that the net profits of camelina–wheat system could be closer to those in the fallow–wheat system. However, higher grain price and/or greater grain yield of camelina are essential to attract producers to include camelina in their cropping systems. Although the fallow–wheat system resulted in higher short-run net returns, the total biomass production and crop residue return to soil is much greater in camelina–wheat than fallow–wheat rotation, which is likely to improve soil quality and productivity in the long run.