Dual-purpose cover crops and onsite retention of water nutrients

Principal Investigator: Frank Forcella
Organization: University of Minnesota, Department of Agronomy and Plant Genetics
Award Amount: $266,156
Start Date: 7/1/2014 | End Date: 6/30/2017
Project Manager: Luke Stuewe (Luke.Stuewe@state.mn.us)

Research Objectives

This project assessed cover cropping techniques that have dual purposes: improving water quality while simultaneously maintaining or enhancing financial profitability in Minnesota.

This research focused on comparing cash-generating winter oilseed crops (camelina and field pennycress), more traditional cover crops (rye and radish), and conventional winter-fallow systems. Each cropping system was evaluated for the following.

Agronomic variables:

Seed and oil yields
Disease, weed, and insect pressures
Harvest dates

Environmental variables:

Water use
On-site use and retention of nitrogen and phosphorus

Economic Variables:

Input costs
Economic return

This research was conducted along a gradient that spans from the northwest to the southeast region of Minnesota. Performing the research in different regions tested the limits and feasibility of growing winter oilseed crops across Minnesota.

Background

Cover crops, in general, provide crucial environmental services including nutrient scavenging, weed suppression, soil erosion protection and runoff reduction. Recently developed dual-purpose cropping systems may provide environmental benefits and provide economic advantages to Minnesota farmers. Winter camelina (Camelina sativa) and field pennycress (Thlaspi arvense L.) are winter-hardy oilseed crops that could generate cash for growers in the spring prior to planting traditional soybean cash crops.

Project Description

Researchers conducted three, nearly identical experiments in three different locations; Roseau, Morris, and Waseca, Minnesota.

Null hypothesis (hypothesis being tested): A cropping system including winter camelina or field pennycress will be equivalent to a standard soybean crop in terms of oil yields, economic return, water use, and fertilizer uptake and retention.

Alternative hypothesis: a field pennycress/soybean or winter camelina/soybean cropping system has higher oil yields, economic returns, water use, and fertilizer uptake and retention when compared to a standard soybean crop followed by winter fallow.

Methods and Data Collection

close up photograph of camelina seeds and flower
Camelina seed and flower

Deliverables

Results of the comparative yields, gross returns, and net returns for each cropping system tested
Results for soil water use, nutrient uptake, and offsite sediment movement related to the cropping systems tested.
An Extension Bulletin that acts as a grower’s guide and explains the financial and environmental benefits of the dual-purpose cropping system.
A peer-reviewed journal article based on crop yields and net returns and a peer-reviewed journal article on the ecosystem services provided by the dual-purpose cropping system.

Education and Outreach

Farmers

The University of Minnesota Research and Outreach Centers will host field days focusing on dual-purpose cropping systems. The locations include Morris, Lamberton, and Waseca.
Development and distribution of a “Dual-cropping System Grower’s Guide”.

Students

Support of a graduate student and postdoctoral research associate.

Scientific community

Development of peer-reviewed journal articles
On-campus seminars
Field days focusing on dual-purpose cropping systems