Iowa Learning Farms Webinar to Explore Lessons Learned from Using Cover Crops to Reduce Nitrate Losses

DSCN0571Even with excellent nutrient management, nitrate losses from corn and soybean fields can occur because these cash crops only grow and take up nitrate and water for five months of the year. Cover crops like winter rye can be an effective strategy for reducing nitrate losses to groundwater or tile drainage because they can take up water and nitrate during the period between harvest and planting of the next year’s crop.

Dr. Tom Kaspar, Plant Physiologist at the USDA-ARS National Laboratory for Agriculture and the Environment, will share his lessons learned over his storied career researching the use of cover crops and no-till to improve water quality and soil health in corn and soybean production systems.

DATE: Wednesday, December 13, 2017
TIME: 12:00 noon
HOW TO PARTICIPATE: Log on as a guest shortly before 12:00 p.m.:
https://connect.extension.iastate.edu/ilf/

More information about this webinar is available at our website. If you can’t watch the webinar live, an archived version will be available on our website: https://www.iowalearningfarms.org/page/webinars.

Julie Winter

“Chipping Away” at What We Don’t Know About Bioreactors

LauraLast week, Dr. Laura Christianson joined us for our monthly Iowa Learning Farms webinar. Christianson has nine years of experience focused on agricultural drainage water quality and denitrification bioreactors for point and nonpoint nitrogen treatment.

Bioreactors: What We Know

Laura’s experience with bioreactors over the past nine years has led her to study bioreactors with many shapes, sizes and designs. She authored in a meta-analysis on bioreactors that synthesized existing research.

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For bioreactor basics, the meta-analysis found that bioreactors can remove an average of 25-45% of the annual N load leaving a field, although a range of 10% to 100% of N load reduction has been seen. The cost of a bioreactor that treats 50 acres was approximately $10,000. The analysis also found that woodchips in a bioreactor can last approximately 10 years, but a range of 7-15 years has been seen. The woodchips need to be changed not because the bioreactor is running out of a carbon source, but because woodchip degradation causes hydraulic performance decline within the bioreactor. The meta-analysis also investigated different factors that impact nitrate removal effectiveness in a bioreactor. Some of these factor are:

Hydraulic retention time
Water should be retained within a bioreactor for a minimum of six hours. Great visuals and an explanation are covered in the webinar.

Water temperature and age of bioreactor

Water tempWater lower than 43 degrees F affect nitrate load reduction potential. In the first year, bioreactors are incredibly efficient at N load reduction as microbes begin to feast on available carbon and dissolved oxygen in the water. However, Laura says, “Once your bioreactor is more than a year old, that’s when you really settle in to know what your long-term nitrate removal performance is going to be.”

Porosity of the woodchips
wood_creditThere was no significant difference in N removal when using different types of wood (hardwood vs. softwood) in a bioreactor. However, the physical properties of the wood matter. Use chips with particles size between ½ inch and two inches instead of shredded or mulched wood.

 

Bioreactors: The Future

Future research on bioreactors is moving us beyond the first generation of bioreactors.

Bioreactors with bafflesbaffles_credit
Plastic baffles in the bioreactor route the water through the woodchips so all woodchips are utilized in the denitrification process.

 

Paired_creditPaired bioreactors
Two bioreactors are installed side-by-side. One serves as the primary bioreactor, and bypass water from the primary bioreactor is routed to a second bioreactor to continue N removal on bypass water that would normally not be treated.

in-ditch_creditIn-ditch bioreactors
For areas with ditch drainage, the bottom of the ditch is excavated, woodchips are placed, and wooden check bands are installed incrementally throughout the length of the treated ditch bed.

 

PfilterBioreactors paired with
phosphorous-absorbing filters

Water is routed through a phosphorous-absorbing filter prior to its entry into the bioreactor.

 

If you would like to brush up on your bioreactor knowledge, don’t miss this webinar!

Julie Whitson

Iowa Learning Farms Webinar to Explore Past, Present and Future of Bioreactors

05-17 BioreactorAs substantial investments in drainage systems continue to be made across the U.S.- Midwest, the use of edge-of-field practices like woodchip bioreactors can help treat tile-drained water and help meet our water quality goals.

Dr. Laura Christianson, Professional Engineer and Assistant Professor in the Department of Crop Sciences at the University of Illinois, will present on bioreactor basics, what we know about how bioreactors work and novel ideas to make bioreactors work better. Dr. Christianson has nine years of experience focused on agricultural drainage water quality and denitrification bioreactors for point and nonpoint nitrogen treatment.

DATE: Wednesday, November 15, 2017
TIME: 12:00 noon
HOW TO PARTICIPATE: Log on as a guest shortly before 12:00 p.m.:
https://connect.extension.iastate.edu/ilf/

More information about this webinar is available at our website. If you can’t watch the webinar live, an archived version will be available on our website: https://www.iowalearningfarms.org/page/webinars

Julie Whitson

Iowa Learning Farms Webinar: Talking Grazing with Joe Sellers

web3Did you miss our webinar with Joe Sellers, Iowa State University Extension Beef Field Specialist, this week? You’re in luck because we archive all of our webinars on our website!

Tune into the webinar to learn more about:

  • Results from long-term grazing studies on the ISU McNay Research Farm in Chariton
  • How pasture helps store more carbon and organic matter than it loses
  • How to manage grass throughout the growing season and your forage supply year-round
  • How to improve grazing through fertility maintenance and grazing efficiency
  • Why water placement is critical and can help with pasture utilization and manure distribution
  • Resources you can use to learn more, including an updated “Pasture Management Guide,” workshops, the Iowa Forage and Grasslands Conference and more in-depth classes such as the Greenhorn Grazing Class and the Iowa Certified Graziers Class

A few great quotes from Joe:

web2

“As graziers, we are really managers of plant leaf area and root carbohydrate reserves.”

“Management-intensive grazing is not intensive grazing!”

 

 

 

Tune into the webinar to learn more!

Julie Whitson

October 18 Webinar to Discuss Management-Intensive Grazing and Grasslands

Pasture and forage acres are critical to soil conservation and the profitability of beef cattle operations. Grab your lunch and learn from Joe Sellers, Beef Field Specialist with Iowa State University Extension and Outreach. Sellers will discuss practices that improve grazing effectiveness and how management-intensive grazing can work on Iowa farms. He will also discuss where opportunities exist to expand grasslands in Iowa.

DATE: Wednesday, October 18, 2017
TIME: 12:00 noon
HOW TO PARTICIPATE: Log on as a guest shortly before 12:00 p.m.:
https://connect.extension.iastate.edu/ilf/

More information about this webinar is available at our website. If you can’t watch the webinar live, an archived version will be available on our website: https://www.iowalearningfarms.org/page/webinars

Julie Whitson

DSCN9818

ILF Webinar Digs into Earthworms and Soil Health

The common nightcrawler, Lumbricus terrestris, is a deep-burrowing worm species that is found in many Iowa crop fields. The presence of nightcrawlers can serve as one indicator of the overall soil health in Iowa’s agricultural ecosystems. Ann Staudt, Assistant Manager of the Iowa Learning Farms, will discuss ILF’s recent research that analyzes the relationship between earthworm populations, cover crops and overall soil health.

midden1While soil health can be difficult to quantify, earthworms are a very tangible early indicator of soil health, long recognized by farmers and gardeners as being beneficial organisms in the soil ecosystem. Staudt hopes that this research will teach us more about the connections between earthworm populations and soil health in a cover crop versus no cover system, and that earthworms can be a simple, straightforward indicator of soil health.

Staudt is an environmental engineer who actively blends scientific knowledge and creative expression through her work and teaching. Staudt holds her MS degree in Environmental Engineering from the University of Notre Dame and BS degree in Chemical Engineering from Iowa State University.

Log on as a guest shortly before 1:00 p.m.: https://connect.extension.iastate.edu/ilf/

If you can’t participate live, watch the archive of today’s webinar (along with all of ILF’s past webinars) on our website: http://www.extension.iastate.edu/ilf/page/webinars

Julie Whitson

Cover Crop Webinar to Focus on Soil Health and Nitrate Retention

As fall cover crops go into the ground, many farmers have questions about how to best manage cover crops and achieve benefits such as soil health and nitrate retention. Dr. Mike Castellano will share his research on how cover crops can best be managed to maximize benefits during the Iowa Learning Farms’ monthly webinar on Wednesday, September 21 at 1 p.m.

corn_in_rye_small“Future gains in crop production and environmental quality will require a systems approach that integrates many disciplines,” Castellano said. To achieve this vision, Castellano uses expertise in soil science and ecosystem ecology to work with a broad range of scientists, managers and policy makers.

Castellano is the William T. Frankenberger Professor of Soil Science and Associate Professor in the Department of Agronomy at Iowa State University. He has a PhD in Soil Science from The Pennsylvania State University.

 

Log on as a guest shortly before 1:00 p.m.:https://connect.extension.iastate.edu/ilf/

If you can’t participate live, watch the archive of today’s webinar (along with all of ILF’s past webinars) on our website: https://www.iowalearningfarms.org/page/webinars.

Julie Whitson