Field Day Recap: Management Matters with Cover Crops!

Cover crops and conservation leases were the theme of an Iowa Learning Farms Women Landowners Cover Crop Workshop held in Marshalltown on June 7.  While cover crops offer numerous benefits out on the landscape, one common theme emerged clearly from the workshop presentations and discussion  — it all comes down to active management when integrating a cover crop.

Allen Burt, who farms 3 miles north of Marshalltown, kicked off the workshop by sharing his experience with cover crops and some of his key management considerations.

He emphasized, “Start with something easy.”  In Burt’s playbook, that means getting oats out on soybean ground as soon as you can in September (drill or broadcast), let them winterkill, and then plant corn into that in the spring.

On corn ground, he suggests starting with cereal rye and a little bit of starter fertilizer (something like a 10-23-23 mix) after the corn is harvested, ideally in early October. The cereal rye will survive over the winter, and then Burt recommends terminating in the spring with glyphosate.

Burt’s recommendations align nicely with the Iowa Learning Farms’ findings, as well, shared at the workshop by Liz Juchems, Conservation Outreach Specialist.

Juchems also shared findings about yield impacts following cover crops. Farmer-partners working with cereal rye reported that in 59 of 63 site-years, strips with cover crops were yield neutral compared to strips without a cover crop – no negative impact on corn and soybean yields. The only significant yield declines were in the first two “learning” years of this long-term study, when producers faced challenges regarding spring termination and planter adjustments to accommodate the additional residue from the cover crop. Over time, those management challenges were overcome to realize cover crop success.

Interwoven with the presentations was an earthworm midden counting hands-on demonstration, as well as lively discussion and dialogue from the 25 people in attendance, including area landowners, operators, and conservation/ag professionals.

One producer in attendance brought up, “The #1 problem in farming today is soil erosion.”  Another producer added to that, commenting that a close second in terms of challenges today is the perception of “This is the way we’ve always done it,” acknowledging there can be some resistance to new practices like cover crops, despite the benefits to reducing erosion, benefitting soil structure, etc.

Charles Brown, Farm Management Specialist with Iowa State University Extension and Outreach, noted, “When you talk about using cover crops, it’s a different management practice – you can’t just do the same thing you’ve always done.”  He shared with the group his own experience with growing cover crops, as well as numerous suggestions for landowners and operators to work together to integrate cover crops into a written conservation lease.

Farmer Allen Burt emphasized, “As a producer, my message for you is, ‘Get out there and try it!  If you have the right attitude, you can do it! … Cover crops are a small investment to make things better in the long run.”

Ann Staudt

This workshop was put on as a partnership of Iowa Learning Farms and Marshall Co. Farm Bureau.

New online tool helps farmers assess value of cover crops

Iowa State University Extension and Outreach, in partnership with Practical Farmers of Iowa, has launched a new Ag Decision Maker tool on their website to help crop and livestock farmers assess the economics of cover crops in their operations.20150428_092027

The Economics of Cover Crops tool consists of three in-depth budgeting worksheets designed to help farmers analyze the costs and benefits of cover crops – and paths to profitability – in their row crop operations with or without the integration of livestock:

  • Cover Crops Budget looks at the economics of cover crops in systems without grazing or harvesting
  • Grazing Cover Crops Budget estimates the costs and benefits with grazing or harvesting for feed
  • Grazing Cover Crops Results uses farmers’ farm data to calculate the actual economic value of grazing or harvesting cover crops from the prior year

The unique three-in-one tool was developed to let farmers see the potential added value they could gain when cover crops are used for forage. Recent Practical Farmers of Iowa on farm research has found that, when properly managed, grazing cover crops can result in sizeable profits within the first year.

The worksheets are available online and were created with funding by Iowa Department of Agriculture and Land Stewardship’s Water Quality Initiative.

Help available to use the tool

To ensure farmers feel confident using the new tool, Meghan Filbert, Livestock Coordinator with Practical Farmers of Iowa, is available to help farmers gets started. Contact her at (515) 232-5661 or meghan@practicalfarmers.org with questions or to request assistance working with the tool.

Liz Juchems

 

Grass species most popular cover crops among Iowa farmers

Grasses, brassicas, legumes – oh my! With so many cover crop species to choose from, how does one decide?

One way is to look at what the producers in your area are using and observe how well those species will help reach the goals you have for your land. Here are some examples of cover crops by group:

  • Grasses = cereal rye, oats, wheat, triticale, barley
  • Brassicas (plants producing a tap root) = radishes, rapeseed, mustards
  • Legumes = red clover, crimson clover, hairy vetch, peas

cover-crop-species1-e1523647673791.jpg

To help identify what cover crop species are being used across the state, we asked our 2017 field day attendees.  Responses to our 2017 Field Day Evaluation Report are similar to our conclusions of what works best in our cover crop species research projects. Grasses are the best choice of cover crops for a corn/soybean system. Cereal rye was the mostly widely used species, with 85% respondents listing it as what they seeded in 2017. Reported brassica and legume usage is down overall compared to 2016 data.

Cover Crop Species

For those looking to get started with cover crops, we recommend the following:

Oats Before Corn & Cereal Rye Before Soybeans

These cover crop species are relatively inexpensive, readily available and easy to establish. Oats will winter kill whereas cereal rye is winter hardy and requires spring termination. That is why we recommend using it before soybeans to provide the best opportunity for first time cover croppers to learn how to manage the cereal rye and minimize negative yield impacts.

Liz Juchems

Tips for rye termination after a short growing season

ICYMI – A recent article from Iowa Farmer Today highlights tips from ISU Extension and Outreach for terminating a rye cover crop following a reduced growing season.

Given the limited fall growth and persistent cold weather this spring, there will likely be less cover crop growth compared to recent years. This could lead to termination challenges for those that are not prepared.  With three methods of termination, there are options for producers to choose from to find the best fit.  These methods include: herbicide (most widely used), rolling/crimping (after pollen shed) and limited tillage.

CC-TipsForTermination
Here are some keys for successful herbicide termination:

  • Translocated herbicides, like glyphosate, work best on actively growing plants
  • Spray on sunny afternoons when daytime temperatures are 60°F or above & nighttime temperatures stay above 40°F
  • Avoid spraying in the early morning or evening hours

Timing of termination recommendations:

  • Ahead of corn = terminate 10-14 days before planting
  • Ahead of soybeans = terminate 1-2 days before planting to maximize spring growth

For more tips, check out our earlier post Cover Crops: Tips for Termination!

Liz Juchems

Cover Crop Acres Grow But Rate of Growth Declines in 2017

According to the Iowa Learning Farms 2017 Field Day Evaluation Report, Iowa cover crop acres grew last year by approximately 22% to 760,000 total acres. While the positive growth with shrinking profit margins is notable, the rate of growth is ten percent less than the growth measured in 2016, and still well below the goal of 12.5 million acres of cover crops called for in Iowa’s Nutrient Reduction Strategy.

Cover Crop Acres 2017 (2)

Many of the new acres were planted by experienced cover crop farmers. The majority (69%) of respondents to Iowa Learning Farms’ year-end evaluation questionnaire started seeding cover crops at least three years ago. Only eleven percent of respondents reported implementing cover crops for the first time on their land last year. Those respondents with cover crops reported an average of 46% of their total row crop acres in cover crops—6% more than in 2016.

Cost Share Cover Crops 2017. (2)The overall percentage of farmers who are using cost share to seed cover crop acres has increased by seven percent over four years of Iowa Learning Farms evaluation data. Of the respondents seeding cover crops in 2017, 65% of them did so with the assistance of cost share.

Iowa Learning Farms sponsored 29 conservation field days and workshops in 2017 on cover crops, strip-tillage, saturated buffers, prairie strips and more. These events drew an attendance of 1,280 people, primarily farmers and landowners (89%). Twenty-seven percent of Iowa Learning Farms field day attendees were female.Eval Cover (2)

In January 2018, 580 farmers and landowners who attended Iowa Learning Farms field days were mailed an evaluation questionnaire to investigate whether they made changes to their farming practices. In a one-month period, 251 evaluation questionnaires were returned for a 42% response rate.

The Iowa Learning Farms 2017 Field Day Evaluation Report can be found at www.iowalearningfarms.org.

Established in 2004, Iowa Learning Farms is building a Culture of Conservation by encouraging adoption of conservation practices. Farmers, researchers and team members are working together to identify and implement the best management practices that improve water quality and soil health while remaining profitable. Partners of Iowa Learning Farms include the Iowa Department of Agriculture and Land Stewardship, Iowa State University Extension and Outreach, Leopold Center for Sustainable Agriculture, Iowa Natural Resources Conservation Service, and Iowa Department of Natural Resources (USEPA section 319).

Liz Juchems

Webinar highlights cover crop, water quality connections

In case you missed it, this past week’s Iowa Learning Farms webinar offered an excellent overview of the research findings related to the potential of winter cover crops to reduce nitrate leaching in corn and soybean cropping systems. Dr. Tom Kaspar, plant physiologist with the USDA-Agricultural Research Service, shared results from numerous studies that show the ability of cover crops to reduce nitrate concentrations and loads in tile drainage water.

The press headlines about nitrates and water quality are seemingly ubiquitous, and Kaspar provided solid data that help to paint a complete picture of the challenges and opportunities. Our land uses have changed dramatically, and over the past 60-70 years, our cropping systems have likewise changed dramatically with significant reductions in small grains, hay and perennial vegetation.  With corn and soybeans having a 7-month brown gap when they are not actively uptaking nutrients, that leaves a significant amount of time with nutrients vulnerable to leaching.

However, Kaspar’s research clearly demonstrates that cover crops help transition that brown gap to a green gap, providing the ability to “capture” nutrients in the soil that would otherwise be vulnerable to leaching loss. One of Kaspar’s long-term research studies in central Iowa found that rye cover crops in a corn-soybean cropping system reduced nitrate concentrations in tile drainage water by 57%. Additional studies by Kaspar and collaborators around the state found nitrate reductions of anywhere from 20% to 40%. This variability is expected, with different amounts of cover crop growth, weather, rainfall, soil types, tile systems, and field histories.

Kaspar also pointed out that it takes quite some time for nitrate to move through the system – there is a noticeable lag effect.  For instance, Kaspar and collaborators found that nitrate concentrations in subsurface tile drainage continued to decrease through the summer, long after spring cover crop termination.

Check out the full webinar, Lessons Learned from Using Cover Crops to Reduce Losses of Nitrate for 15 Years, on the Iowa Learning Farms webinar archives page.  And to hear more perspectives from Dr. Kaspar, tune in to Episode 06 of the Conservation Chat podcast!

Ann Staudt

Why the delivery scale?

When it comes to monitoring water quality, there are quite a number of factors to consider: What are you monitoring for? How is land utilized within the targeted area?  How, when, where, and for how long will water samples be collected? Under what flow conditions? The scale at which you monitor really makes a difference!

The plot scale is valuable for looking at the impacts of specific in-field management practices. Plot scale (or field-scale) monitoring is where most of the pollutant export and delivery data come from that informed the Iowa Nutrient Reduction Strategy. Treatments can also be easily replicated on the plot scale. However, it’s challenging to properly scale up plot-level measurements to the area of practice implementation to truly assess water quality impacts across landscapes and with multiple practices.

Monitoring on the watershed scale allows us to look at the collective impacts over a much larger land area.  For instance, watershed-scale monitoring provides a broad picture of water quality challenges and aids in the identification of impaired waters. When monitoring on the watershed scale, measurements inherently include what’s happening on the land (field scale practices), plus field-to-stream transport, plus in-stream processes (bed and bank processes).  It certainly provides a comprehensive look the big picture, but you can’t “sort” out the different contributions of what’s happening in-field versus in-stream.

In between these two lies the delivery scale.  Delivery scale monitoring occurs at the point where water is delivered to a creek or stream. For instance, with drainage research, this would be the point where the tile main surfaces and water empties into a stream. In a nutshell, the delivery scale reflects the direct water quality impacts from an agricultural area, minus the potential confounding effects of in-stream processes like bed and bank erosion. Here at the Iowa Learning Farms, we’d argue that this is truly a sweet spot for looking at the impacts of specific conservation practices.

You need to monitor at the delivery scale if you want to know specifically what the agricultural impacts are.  That’s exactly what we’re striving towards with the Conservation Learning Labs project.

Within a small watershed area (several hundred acres), can we get a substantial percentage of producers adopting a conservation practice, like cover crops, and then measure corresponding water quality improvements at the delivery scale?  Modeling suggests so, and this project will quantify what nutrient load reductions are actually realized thanks to large scale, targeted adoption of cover crops.

Cover crops were seeded for the first time in fall 2017 within our two Conservation Learning Labs project sites.  Stay tuned for results as we look at the water quality (and soil health) impacts of substantial cover crop adoption on the delivery scale!

Ann Staudt