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

On-the-Ground Experience with Cover Crops

“What’s building organic matter worth to you?”

For Prairie City, IA farmer Gordon Wassenaar and tenant farmer Will Cannon, it’s worth using no-till and cover crops on every single one of their 1300 acres of cropland.  In a field day hosted by Iowa Learning Farms, Jasper Co. NRCS and SWCD, Wassenaar and Cannon shared their perspectives on cover crops and how they can be very successfully integrated into corn and soybean cropping systems.

Wassenaar, who has farmed for over 50 years, stated that he first got into cover crops for the purpose of protecting the soil from erosion. He started with cereal rye, broadcast seeded from an airplane.

As time has gone on, Wassenaar’s reasons for using cover crops have evolved from simply erosion control, to improving the structure and functioning of the soil — raising soil organic matter, aggregate stability, and water holding capacity. Cannon commented that on top of that, another big benefit is feeding the biodiversity of the soil, like the beneficial mycorrhizal fungi, all while growing a healthy crop.

Timing and seed-soil contact are two big factors with establishing successful cover crop stands, and it’s a balancing act between the two. Aerial broadcast seeding (or interseeding with a high clearance vehicle) allows for a larger window of time for fall growth, while drilling provides greater seed-soil contact. Today, Wassenaar and Cannon have moved to drilling all of their cover crops, ideally getting them in the ground 24 hours or less behind the combine.

When asked about the financial considerations of cover crops, Cannon responded, “We’ve got to be willing to be a little creative and inventive to make it work.”  And they certainly are.

Cannon outlined several approaches they are taking to minimize costs and improve efficiencies in their operation:

  1. Shop around for cover crop seed.
    Compare prices with different cover crop seed houses in order to get the best bang for your buck. Wassenaar and Cannon are even considering growing their own cover crop seed down the road.
  2. Consider your seeding techniques.
    Aerial broadcast seeding and custom planting carry a significant cost.  Cannon explained that they have moved to seeding all of their acres now with a drill, which has provided greater seed-soil contact, and thus improved the seeding efficiency in terms of the number of seeds that actually grow (they’ve subsequently optimized/reduced seeding rates accordingly).  They are also saving dollars through the use of a smaller 120hp tractor and a cover crop drill that was bought used.
  3. There are a lot of good programs out there that can help.
    Take a look at the conservation programs and personnel on the federal, state, and local levels that can help out.

With years of experience implementing conservation practices of no-till and cover crops, Wassenaar reflected on how much the technology advances make conservation readily doable today.

“Back in the day, we plowed because we didn’t have planters that could plant into high residue. The equipment is so good today, that now we can plant into just about any residue.  … With cover crops out there, it’s almost like planting onto a mattress.”

Wassenaar is clearly passionate about conservation, and left field day attendees with the following thoughts:

“I don’t know any other way you can farm and save your soil than with no-till and cover crops.  … I’m convinced that if Iowans take care of their soil, the soil will take care of Iowa.”

Ann Staudt