1. NRCS Soil Health and Cover Crops February 27, 2015
General introduction
National initiative to promote soil health. Ray presented earlier today about soil health principles. With the soil health discussion there is lots of talk and discussion of cover crops and how they fit in the soil health discussion but also our area of limited moisture, high ET, and temperature fluctuations.
Ray talked about the soil biology, tomorrow you will have the opportunity to see the rainfall simulator and hopefully tie all this together. Today we wanted to go through some things that we work through with producers for planning cover crops or a soil health system.

2. Soil Health Terminology
Soil Health The continued capacity of the soil to function as a vital living system that sustains plant, animal, and human health. Cropping System The crops, crop sequence, and management techniques used on a particular field over a period of years Cash Crop A crop grown with the intent to harvest seed/root for market. Forage Crop A crop grown with the intent to harvest/utilize forage or biomass for market through grazing or haying. Cover Crop Crops grown for seasonal cover and other conservation purposes. Primarily used for erosion control, soil health improvement, and water quality improvement. Can also be used as green manure and/or mulch.
Some of the popular press and even different agencies and producers interchange some terminology. So before we get too far into things and so everyone is on the same page some definitions.
Soil Health
Cropping system – This includes all your crops, the crop sequence or rotation, even tillage system.
Cash Crop – Basically your marketable crops such as wheat, corn, milo, soybeans, canola.
Forage Crop – This is for those of you that graze out wheat pasture or plant a crop for hay. In the future this may include biomass for cellulose production.
Cover Crop

3. Soil Health Planning Principles
Manage more by Disturbing Soil Less
Use Plant Diversity to Increase Diversity in the Soil
Grow Living Roots Throughout the year
Keep the Soil Covered as Much as Possible
* Manage erosion, compaction, and temperature/moisture
* Goal: To create the most favorable habitat possible for the soil food web.
Protect the Habitat Provide Food
These are the ‘keys to the kingdom’ of improving soil quality and sustainable agriculture because they focus on soil biology and soil ecology; what really runs the soil and all that it does.
Manage more by disturbing less obviously deals with reducing tillage operations and other practices which affect soil structure such as overgrazing.
Increasing diversity can be done through crop rotations, forage crops, and cover crops
Growing living roots throughout the year can be done with crop rotation as well as cover crops.
Keeping the soil covered can be done with cover crops but also with crop rotations and limiting those disturbances such as tillage or heavy grazing pressure.
Arid environments such as western OK, we have to also think about things such as erosion, compaction, temperature and moisture. These affect the 4 main principles especially in fragile environments when we are possibly grazing, growing low residue crops, or facing drought situations.
These principles need to be remembered when thinking about soil health and planning a cropping system.
Despite popular press and many cover crop promotors, soil health is not just planting a cover crop.
Manage all inputs and disturbances for Soil Health
Soil Health is NOT just Cover Crops

4. Soil Health Planning
No “cookie cutter” or “one size fits all” soil health system.
Crop Rotation
Tillage
Cover Crop
KISS – don’t overthink it
It is not 100% successful
Plan on a failure at some point
Flexibility adds to the diversity
Start simple and add as comfort level increases.
Requires planning but also adaptability and flexibility
Based on those maps, it should be no surprise that there is no “cookie cutter” one size fits all cover crop or soil health system. There are popular press articles as well as university fact sheets from the eastern US and corn belt that say “for health soils plant 60 lbs of rye after corn or bean harvest.” We can’t do that here for multiple reasons and most all end in disaster. You know your operation and where you limitations are, what you can grow, what you need to do to manage residue, and how you can be profitable. What works for your neighbor may or may not work for you.
Is there anyone in the room that has never had a crop failure? Why do we use failure as a reason to not try a new practice, crop, or cover crop. Most successful cover crop and soil health proponents advocate they plan on failing at some point. They learn from it and make adjustments.
We have to keep it simple and not over think it. A crop system, adding cash crops, or forage crops for any goal requires planning but also adaptability and flexibility as weather, markets, and objectives change. Producers should look at simple ways to change. There is no reason to think we have to go immediately out and plant a 12 species mix and figure out how to justify a $35/ac seed cost. Maybe add a $25/ac forage crop and earn some income or start with a single or two species cover crop and try to plant it for $20/ac.

5. Soil Health Planning What is the objective/goal and timeframe?
Where are voids in cash crop rotations/timeframe/season?
What is the preceding cash crop and following cash crop?
Nutrients lost or captured from last crop?
C:N Ratio
High C/N Ratio = immobilizes N
Low C/N Ratio = mineralization
Can a cash/forage crop accomplish the goal?
Flexibility
Drought, flood, risk, markets
System has to work for your operation
Tillage doesn’t mean we can’t plan diversity
Works for one won’t work for others
When we work with producers, we try to work through a series of questions that when you work through this, help narrow down the options and determine which options best fit your crop system.
What is your objective or goals?
Generally the more specific the objective, the less diversity
Where are voids in the cash crop rotation
This can be a lengthy process if it is a long rotation. Intense rotations may not require a cover crop
What is the timeframe or season of when you want/need the cover
Generally the tither the planting window the less options. A 45 day window with moisture can produce a cover crop. Using a cover crop for mulch and weed barrier may require more time to grow enough biomass.
Adding a cash crop or forage crop may accomplish the same objectives. Compaction, diversity, SOM and erosion can all be affected by rotating the crop. Plus you get the added bonus of direct income potential from grazing or the cash crop. Many of you may have intense enough rotations that a cover crop isn’t needed.

6. Planning Cover Crop Mixes
Single or Multi Species
Certain resource concerns require multiple species (2 or more)
Start simple and add over time
Pest Management
Green bridge to next crop
Pests moving from one crop to the next
Resource Limitations
Planting capabilities (NT Drill, small seed box, broadcast, etc)
Neighboring crops
Termination timing
Must be able to terminate when needed
Have a Plan B
Tillage, Rolling, Mowing
Manage residues
Remove and replace as mulch
Tillage/seeding equipment
Once we have determined that a cover crop is the best fit, then we work through questions again to determine our species to plant just like you would for different crop varieties.
Once again, need to know the objectives and timeframe. Specific objectives such as warm season for nitrogen fixation, very specific and limited options where as warm season biomass production is very broad and lots of options.
Then eliminate those species that don’t fit the objective and accomplish it in the timeframe. No reason to plant a cover crop that doesn’t meet your objectives in that time frame.
Lots of debate over single or multiple species, you can find experts that will claim either one is better. If participating in some NRCS programs, some resource concerns require 2 or more species. That is all dependent on the program and concerns. Some producers are planting single species because they are keeping the option open to harvest it for a cash crop. On the other hand, there are a lot of producers that plant an mix of species because that adds diversity and it increases the odds that if something goes wrong, at least one species will germinate. There is research out there that supports symbiotic relationships between different plant species and when growing together, production is increased.
For pest management we need to be sure to not plant something which harbors pests over to the next cash crop or a green bridge for disease.
Also consider what limitations you may have. A lot of districts have small drills with small seed boxes it is just hard to cover a lot of acres. Some of the species you may want such as rye or ryegrass may not be appreciated by your neighbors. Maybe you don’t want to use certain chemicals or can’t afford the risk. All things to consider.

7. Oklahoma Cover Crop Species
Warm Season
Millet, Sorghum, Corn
Turnip, Radish
Mungbeans, Cowpeas
Cool Season
Rye, Wheat, Ryegrass,
Canola, Rapeseed
Crimson Clover
Seed size vs Seed cost

8. Take Home Thoughts
Cover crops are valuable tool to add diversity and residues
Managing for Soil Health requires management
Local NRCS Office has tools available to help with cover crop planning
Cover crop calculator
Cover species guide
Take home thoughts
Cover crops are not the only practice out there to add diversity and residues. Adding a cash crop into the rotation can help with both of these.
If you are conventional tillage and a very simple rotation, find some primers and diversity to add to the system and improve the likelihood of success in your cash crops.
This environment is extremely fragile and dynamic, overgrazing or tillage at the wrong time can be very detrimental to the next crop. Longer rotations help with this but don’t alleviate it. There are instances where crop residue was in the field providing protection from wind erosion, a cover crop was planted that never germinated and the reside was gone.
As with all things management is required. Doesn’t matter if it is soil health or cover crops, have to manage the system.