Subsurface Irrigation ' Aerogation to Improve Productivity and Reduce Nutrient Movement

Subsurface Irrigation ' Aerogation to Improve Productivity and Reduce Nutrient Movement

Summary

WORK ACTIVITIES

Grant funds were used to install drip tape in two new fields along with PVC lines from pumphouse and evaluate data and adjust treatments.

RESULTS SO FAR

The objective was to compare an irrigated field to aerogated field. Fields were 5 acres and 7 acres, planting populations were 28,000 ppa, 190 lbs of starter was added to both fields. 5 acre field was injected (aerogated) with microbubbles. A ten lb pressure drop is included in the line near an air intake (venture valve) to add bubbles.

All other treatments were identical.

Every load of corn taken off the fields was weighed. The irrigated control field yielded 107 bu/ac.The aerogated field yielded 197 bu/ac. The dry field control yielded 119 bu/ac.The yield on standard center pivot irrigated field was 174 bu/ac.

40.25 inches of rainfall from May 1 to Oct 1.

2.5 inches of irrigation water was applied during the season to both fields. Fertilizer was applied 12 times from June 29th to August 24th to the drip tape. Total amount of N (28%) applied in season was ~92lb.

Energy cost of irrigation on an acre basis $16/ac for center-pivot and $9.40/ac for the SDI treatment.

WORK PLAN FOR 2017

We will conduct soil tests pre-season and work with Coop agronomists on fertility plan.

We will install new soil moisture monitors and install phone app for data collection and to operate irrigation system.

We will collect yield data again for both treated and control fields. All agronomic cultural practices will be standardized across fields.

Salinity will be measured in the soil profile to identify differences in N leaching to see differences between SDI and center pivot water/fertilizer movement.

Another field day will be held in summer, 2017. Media will be invited and promotion will be done to increase awareness.

OUTREACH

Field day was conducted on July 21st in conjunction with University of Minnesota-Extension Becker Irrigated Field Station tour. 30-35 people attended the field day.

Another field day will be held in summer, 2017. Media will be invited and promotion will be done to increase awareness.

Collaborators: