IT sounds Like You are Finding what works for YOU, on Your farm in Iowa

Soil Microbes are just that, regardless of tillage, No till, if all else is =

No-Till Failures on heavy CLAY, For Many reasons

1. Lack of fundamental and basic Soil Chemistry and management skills.

2. Delusional Expectations, usually from Mythical and or a Lack of Adequate, or Miss information received from magazines, Extension and Chemical Co. meetings supporting and sponsoring the No Till  Movement.

NO TILL IS BIG BUCKS FOR the Market , Insecticides, Fungicides, Specialty equipment, Equipment attachments, Specialty, High Mark up Fertilizers. etc. etc. etc.

3. Each and every situation is different and needs specific and Individual Management skills, Practices.

4. From My Person observations over the past 40 years

many  Farmers converting to No Till Had management and weed control issues to begin with. Some were Under capitalized.

The Farmers that were Top Notch Managers, the Minority on Heavy Clay soils, did make No till work and are No tilling today.

( Some? Most of those Knife in NH3 so they are essentially Strip Tilling as far as I am concerned. )

4. Many went into No-Till with soils that were Poorly drained, Low PH. or High magnesium, High Free Salts and Major soil Deficits and Imbalances. No ? or very Low soil Percolation and sever compaction issues in some areas.

5. soils with Underlying Blue or Grey Clay are NOT, In any way conducive to long term successful No Till Yielding Positive and Economic returns.

6. I feel it takes 3 to 6 years to get Some, certain and specific soils conditioned, ready for Productive, Profitable No till.

True, NO-Till  Takes very Top Notch management and at times, High input , Up front expenditures on these tight Clay

soils.

The management of Less, Little or Minimum Compaction is critical.

The Management of Soil Oxygen and Soil Percolation are Critical. 

PH. soil Calcium, Soil Magnesium and P, Yes, good available P is so Very Critical. 

IT Can, and Does Take More $$$ inputs to grow a Bu. of any grain Under Pure, No-Till management systems on Heavy Clay, than with strip till, or conventional tillage systems.

(  Warning  ) A MUST, have the County come out and do a Soil Percolation Test, To determine the ability to proceed ahead ? and jump into No till. Or to Determine if you need to make some major changes and prepare for No-Till 3 to 5 years from Now.

Now North central , Eastern Ohio soils into PA can work well for No-Till sucess

South of, or close to Route 70 across the Corn belt has a MORE Favorable soil structure for No-Till

Heavy Clay Content ???  North Central Ohio, Parts of Northern Indiana and parts of Wisconsin and  Minnesota, Beware

If You have good natural drainage, Good to High Balanced fertility, High Soil Humus- Organic Soils, High content of Sand and Silt soils.

Then NONE of the Above is Relevant TO, or for YOU.

Just my personal opinion from Personal observations 

John