Filling soil health prescriptions with targeted cover crops

Filling soil health prescriptions with targeted cover crops

Summary

In 2010 we trained two additional extension educators in interpreting the Cornell Soil Health Test for the purpose of finding opportunities for using cover crops to overcome production limitations identified by the test. We collected Soil Health Tests on several additional farms, and worked with growers to identify management goals revealed by the test and to select cover crops to reach those goals.

Objectives/Performance Targets

The performance target is that participating growers will, by increasing their soil health through the use of appropriate cover crops: Increase yield by 10% on targeted fields due to better tilth, lower root disease, lower weed pressure and more effective cultivation. Increase the value of their early crops by 10% due to timelier planting and higher quality. Reduce their applied N fertilizer by 20% due to nitrogen scavenging or fixation by the cover crop. Reduce the cost of mitigating runoff.

Accomplishments/Milestones

We provided initial training to two new extension educators, and have scheduled a more comprehensive training for the four recently added participants for January 2011. The additions were necessary because John Mishanec retired. John’s expertise will be missed. In his place, we added two new extension participants who are being trained: Amy Ivy in Essex and Clinton Counties (across the lake from Burlington) and Jeff Miller in Oneida Co in the Mohawk Valley. The change provides an opportunity for greater impact in increasing the capacity of extension educators to provide cover crop recommendations and soil health interpretation.

Through an allied project with other funding, three additional extension educators in Northern New York received training in crucifer cover crops and did demonstration plantings.

Thomas Björkman participated in a national workshop, sponsored by the Walton Foundation, on cover crop use for reducing nitrogen leaching. The workshop provided information and contacts to help increase our ability to mitigate nitrogen leaching in the project area.

Thirteen extension educators attended Björkman’s training workshop at the 2010 Food and Agriculture In Service conference.

Carol MacNeil held two field days that brought in growers from Western New York, and strengthened ties with

Increase integration with Managing Cover Crops Profitably. The website was revised in summer 2010 with better appearance, updated information, thorough links and easier navigation.

Strengthen the basis for recommending specific cover crops. The field research has continued with a cucumber crop grown after the second season of cover crop, then replanting to the same cover crop on each plot. Both four July-planted and seven August-planted cover crops are raised with four replications in each of two fields. We expect to raise beets as the vegetable in 2011 to show differences in growth that reflect soil health.

Summer growth produced roughly one ton per acre of shoot biomass for all the cover crops. Of the early summer cover crops, only sudangrass produced more biomass (2 t/ac). The late summer cover crops in the 2010 planting produced 1 ton per acre for all but triticale, which produced 2 tons of dry matter in the fall. The overwintering cover crops (rye, triticale, forage turnip and annual ryegrass) from the late summer 2009 planting produced about 2 tons of dry matter by the end of April 2010, when they were incorporated.

Cucumber yield in the early summer cover crop trial was 6.5 tons per acre in the bare ground, with the same yield following buckwheat or yellow mustard. Sudangrass produced a 25% yield increase, whereas it was halved after annual ryegrass. The overwintering annual ryegrass left the field difficult to prepare and the decomposing residue was likely competing for soil nitrogen.

Cucumber yield following the late summer cover crops. There was no statistically significant difference in yield with a mean yield of 6.5 tons per acre and the statistical power to detect a change of 1.0 tons per acre. We expect the third cycle of cover crops to begin giving detectable changes.

The second cycle of cover crops did not yet produce statistically significant effects on soil parameters. Surface compaction after cucumber establishment was in the good range for all treatments, with each being within the detection limit (±30psi) of the bare ground control (150psi). The summer cover crops have slightly increased the proportion of aggregates larger than 1 mm, but those planted in late summer have not. Soil aggregate distribution analyses from each year will be valuable for detecting changes that precede conventionally detectable responses that seem to come after three to five 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.

Three growers raised cover crops in the 2009 or 2010 season. Most split-field trials are anticipated for the 2011-12 growing season.

Growers who were working with John Mishanec transitioned to a new extension cooperator during the summer of 2010, causing some to miss the planting opportunity for an appropriate cover crop. These growers will plant a cover crop in 2011 instead. That delay may necessitate a limited extension of time at the end of the project to complete the evaluation of impacts.

Two growers raised a vegetable crop in 2010.

• Carol MacNeil inspecting a forage turnip cover crop at a fall field day in Ontario County
• Field Day participants inspect fall growth of forage turnips, Stanley NY October 19,

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 during the soil health session at the 2010 Empire Fruit and Vegetable Expo indicates high demand for management recommendations, which we will be providing through this project.

• Molly Shaw describes soil health improvement on a tillage-intensive farm by using ryegrass between plastic-mulched beds

Collaborators: