Idea Transcript
Cover Crops & Soil Health In Minnesota
April 4, 2014 - St. Cloud, MN - Doug Miller
Credit and Thanks To: Credit and thanks to…
Dr. Kristine Nichols – ARS Mandan, ND Dr. Elaine Ingham – Oregon State University Dr. Rebecca Phillips – ARS Mandan, ND Dr. James Nardi – University of Illinois Dr. Christine Jones – Australia John Stika – Area Resource SS, NRCS, ND Actinomycete Photo – Soil Microbiology Slide Set 1976, J.P. Martin, et. al. Bacteria Photo – Michael T. Holmes, Oregon State University, Corvallis, OR Fungi Photo – USDA Forest Service, PNW Research Sta., Corvallis, OR Protozoa Photo – Elaine R. Ingham Eroded Landscape Slide 4 and No-Till Conventional Till-No Till Corn, Katheryn DesForge Rice Co. SWCD
Conventional Till vs Cover Cropping Difference in Management Difference in Soil Health
2 Contrasting Soil Management Methods and Two Different Outcomes with the Slake Test What Does This Mean?
Minimal Soil Disturbance
Conventional Till
Conventional Tilled Soil Slakes with Rain Water Does Not Infiltrate and Runs Off
Note: Upside Down
Slaking of soil from rain causes soil crusting. Soil surface is sealed to taking in water!
Rain – Soil Slakes – Seals Up – Water Runs Off - Topsoil Erodes – Plants Washout – Plants Drown Out – Water/Topsoil/Nutrients Enter Surface Water System
Across the Road from the Washed Slope, No Corn Loss, No Drown out, Water Infiltrated Soil for Crop to Use!
Stressed August Corn is Wilting Lack of Soil Moisture
No Residue to Armor Surface Topsoil is Crusted, Cracked, Dry and Hot in August Sun
Cover Cropping Mimics Nature to Build Soil Health
What is Soil Health?
The continued capacity of the soil to function as a vital living system that sustains plant, animal, and human health
What are Soil Functions?
Take in, Hold & Supply Water Supply Nutrients Maintain Biodiversity Filter and Buffer Physical/Structural Support
A Cropping System which Incorporates 4 Principles
Manage MORE by Disturbing Soil LESS Diversify with Crop/Plant Diversity Living Roots in the Soil as Long as Possible Keep the Soil Covered as Much as Possible
Disturb the Soil Less
Disturb the Soil Less – Why? - Vertical pathways for water recharge - plant root and worm channels are destroyed. - Stable soil structure (held together by soil glue) is destroyed by tillage. - Armor on the soil surface is greatly reduced. - Soil Fungi filaments (hyphae) are destroyed. - The flush of oxygen from tillage reduces organic matter in soil, from oxidation.
Bacteria & Fungi – The Soil Glue Makers - Bacteria secrete a substance we will call “Soil Glue” which enhances Soil Aggregate Stability in Micropores. - Fungi secrete Glomalin, another glue which give Aggregate Stability in Macropores. - Fungi supply nutrients to plants.
Armor the Soil with Plants/Plant Residue
Armor & Protect Topsoil – Why?
Protect from wind & rain erosion. Protect microorganisms from extreme topsoil temperature. 70 to 80 is AOK. Residue on surface provides habitat and food for beneficial organisms.
Keep Living Roots in the Soil As Long as Possible
Keep Living Roots in Soil as Long as Possible – Why?
When you have living roots, microbes are active on the roots or rhizosphere. Active Microbes continue to secrete soil glue and make nutrients available. When Plants are green and active, nutrients are scavenged.
Diversify with Plant/Crop Diversity
Diversify with Plant Diversity – Why?
Plants specialize in a function - Fix N, Break up plow pan, Tolerate cold temps Different plants attract various beneficial insects. Some insects eat weed seeds, some insects eat other harmful insects. Crop rotations reduces occurrence of diseases/pests.
Assessing Soil Health Work done in the field
Soil Aggregate Stability Evidence of 2 Contrasting Soil Mgt. Methods!
Cover Crops Visible aggregates & roots
Tillage Blocky, hard, no roots
Assessing Soil Health - Observation
Look at the field. What do you see? Look at the surface – is it crusted or does soil have worm holes and castings at the surface? Dig a hole. What do you see, feel? Earthworms, stable aggregates, roots? Smell the soil. Does it have that fresh earthy smell? That is geosmin, given off by Actinomycetes.
Assessing Soil Health - Tests
Soil Infiltration Rate – Minutes per Inch Biological Activity (Respiration) – Solvita Burst, Haney Test Density - Amount of pore space pH Nitrates
Cover Crop Management
Cover Crop Selector Tool http://www.mccc.msu.edu/
Attend Cover Crop Field Days
Soil Resources Training Doug Miller – Area Resource Soil Scientist, NRCS
Cover Crop Seeding Implements Emerging Technology
Soil Resources Training Doug Miller – Area Resource Soil Scientist, NRCS
What is going on in MN at State Level? - Multiple Conferences MN Ext., SFA - State level collaboration for CC research, studies field demos, education. - SARE, NRCS, SWCD’s and famers went to Burleigh Co. for CC Tour in 2013. - Special Study – Haney Soil Health Nutrient Tool Project. 20 MN Farms
What is going on in MN Counties? - Soil Health/Cover Crop Field Days. - County Soil Health Teams Working on Demonstrations/Assistance/Info/Network - Attend a field day – MN Ext. or SWCD. - Network. Talk to others. - Demonstration Plots on MN Farms
Cover Crop Resources Managing Cover Crops Profitably 3rd Edition http://www.sare.org/ Midwest Cover Crop Council http://www.mccc.msu.edu/ Practical Farmers of Iowa http://practicalfarmers.org Accumulation of Articles http://plantcovercrops.com/ Detailed species information http://www.sarep.ucdavis.edu/database/covercrops
NRCS Soil Health Website http://www.nrcs.usda.gov/wps/portal/nrcs/main/national/soils/health/
Soil Health in Minnesota • NRCS started the soil health campaign in 2012. • In February 2013 MN NRCS held trainings for field staff of NRCS and Board of Water and Soil Resources (BWSR). • Field trainings held Summer 2013 in 6 Area locations • In Minnesota, Soil Health Teams at the state, area & local levels are actively working to promote soil health management in the field.
2 Soils – 18 ft. Apart Both Managed The Same 19 Years Ago Contrasting Management Now
4 SH Principles
Conventional Till