Filling soil health prescriptions with targeted cover crops

Filling soil health prescriptions with targeted cover crops

Summary

In 2011 extension educators used their training in interpreting the Cornell Soil Health Test to identify opportunities for using cover crops to overcome production limitations on cooperating grower farms. Most cooperating growers raised cover crops in 2011 in anticipation of raising the test vegetable crop in 2012. Weather conditions in 2011 made cover crop use particularly challenging. Saturated ground through May delayed crop planting and harvest, eliminating cover-cropping opportunities. Six weeks without rain limited seed emergence, then two tropical storms late in the summer impacted several sites. Nevertheless, we used the opportunities that were available. Continuing research-farm trials monitor the pace at which soil health parameters respond to eight different cover crops used annually for multiple years.

Objectives/Performance Targets

The team is fully trained and the milestone met.

The decision tool is used about 50 times a day, and is widely praised by growers during their presentations in cover crop programs. It was updated with current seed prices and

Strengthen the basis for recommending specific cover crops. The field research has continued with four July-planted and seven August-planted cover crops raised with four replications in each of two fields, retaining the same treatments from year to year. A beet crop was grown after the third season of cover crop. Both ryegrass and sudangrass improved beet stands by 10 to 15%, though subsequent growth was equivalent in all treatments. Annual ryegrass decomposed well this year, where clumpy residue hindered the crop in 2010. A prolonged drought after planting resulted in an uneven beet stand in the trial of August cover crops, therefore yield data did not reflect cover crop effects. Subsequent continuous rain prevented timely planting of the 2011 cover crops; these fields were sown to oats in order to maintain the benefits of having a long cover-crop history. We expect to raise beans as the vegetable in 2012, then plant to the cover crops again with the full battery of soil health parameters measured in Spring 2013.

The third cycle of cover crops did not yet produce statistically significant effects on soil parameters. There is some indication that microaggregates (<0.5 mm) are declining in favor of macroaggregates in the 2-4 mm class. That change is consistent with aggregation occurring in the soil sheath of cover crop roots. We will continue to monitor that parameter to show when it begins changing. We are particularly interested detecting changes that precede conventionally detectable responses that are often reported after five to eight years.

We collected Soil Health Tests on 39 farms with the expectation of testing cover crops and subsequent vegetable growth on many of those farms. Extension field staff worked with growers to interpret their tests and chose cover crops to plant in a split field.

Nineteen growers raised cover crops in the 2009, 10 or 11 season. Several more may try in 2012, though the evaluation won’t be possible in the time period.

The growers who were working with John Mishanec initially transitioned to a new extension cooperator during the summer of 2010. Some planted a cover crop in 2011, but a few ultimately dropped out because of weather, reduced interest or location outside the new cooperators territory.

Accomplishments/Milestones

Two growers raised a vegetable crop in 2010, and nine in 2011. Evaluation was largely subjective, with some benefits as well as some observations of reduced stands

Impacts and Contributions/Outcomes

The primary outcome thus far is an increase in the skill of the extension staff at interpreting soil health tests to find opportunities for cover crop use to reach management goals.

A second outcome is greater attention to the soil health test by vegetable growers. Grower feedback indicates greater understanding of its potential, a significant increase in farmers choosing to use it, and ongoing use of the online decision tool. We continue an aggressive outreach program to raise adoption.

Conference presentations
2011 NOFA-NY Winter Conference. Thomas Björkman and cooperating grower Seth Jacobs presented a workshop to an overflow crowd.
2011 Empire Fruit and Vegetable Expo. Chuck Bornt organized a full session workshop on cover crops and soil health. Presentations by Thomas Björkman and cooperaing grower Jean-Paul Courtens, as well as a workshop by the Cornell Soil Health Team that included selecting cover crops based on CSHT results.
2011 New England Vegetable and Berry Conference, Thomas Björkman and cooperating grower Ted Blomgren each gave presentations on the project.

Field Days
Laura McDermott led field days with presentations by Thomas Björkman and Chuck Bornt at cooperating Windflower Farm and Fox Creek Farm in Eastern NY.
Carol MacNeil led two field days with presentations by her and Thomas Björkman at Branton Farms in Western NY.

Collaborators: