Soil Field Condition vs Lab Tests

These pics are examples of WW crops from two different tillage systems.  Both of these crops look pretty good as of April 13th, 2021.

<-----  Pic on the left is an example of 2021 WW on long term conventional ground.  This  crop was seeded on chemical fallow grnd.

<---- Pic on the left is an example of 2021 WW on ULD grnd.  This area was seeded too shallow and got a late start.

        This winter/spring I had a unique opportunity to run a lab test on two soils that have very different history.  One soil has ~30 years of no-till, with the last eight years being ultra-low disturbance no-till.  The other field, a couple hundreds yards away has a history of one hundred plus years of conventional tillage/cropping, with no no-till history.  Both locations were fairly level with low erosion from weather, although a difference in tillage erosion would be apparent.  The no-till field has a large amount (mat) of residue, and the tilled field has a small amount (a lot of open ground) of residue.   I had high expectations of seeing a dramatic difference in OM, EC, BD, Respiration, and some differences of several macro and micro nutrients.  WHAT A DISAPPOINTMENT!!  Some numbers were the same, and some showed slight differences, but all in all, no revelations.  This lab is not the general run of the mill type that we are all accustomed to.  I have used this lab for a couple of years for different projects. 

    Physically there is a world of difference between these two fields.  April 13th with no measurable rain since March 23rd the ULD grnd was soft to walk across, where the tilled field was hard under foot.  Sinking a 1"diameter soil probe into the ULD field was easy, down the full 4 ft length of the probe, where the conventionally tilled field was very difficult down to ~18", where resistance eased up (maybe even softer than the ULD field in the lower 2'.

        Why didn't the lab show differences as expected?    Two things come to mind.  1)- In my mind this was such a no brainer that I was careless taking the samples.  My process of taking an undefined slice of soil using a narrow trenching shovel was bad technique.  A lot of possible error could result.   2)- This supports my comments on earlier posts about lab testing, and difficulty in trying to show value of no-tilling through our long recognized lab protocols. 

     I'm convinced that no-till deals primarily with the physical component of soil health, but secondary to other processes like biological diversity and nutrient recycling.  Biological activity has to be helped with cover crops and possibly reintroducing microbiological species through well prepared compost and compost teas.   No-till is significant in improving soil drainage, and it reduces destruction of soil organisms community life.    No-till is the first step required for us (in the Palouse) in developing a healthy soil.  With few exceptions, our environment will not support tillage and develop a healthy soil.   Comparing infiltration rate, wet aggregate stability (SLAKE test), visual soil structure, and earthworm count is easy to do and shows dramatically what no-till brings to the table relating to soil health.  Bulk density should be an easy comparison, but the penetrometer is effected by moisture content, soil type and other factors that vary from point to point.   So, what do I conclude?  As many of my earlier posts mention, a no-tillage farming system, is very effective in building soil structure over time.  A no-tillage farming system, when coupled with high surface residue (soil armor) is very effective in controlling erosion from tillage, water, and wind.  A no-tillage farming system is helpful in slowing evaporation when coupled with a protective mat (soil armor) on the ground, and even more effective if also coupled with standing stubble.  Moisture is lost principally through evaporation, not crop production.  Keeping soil surface temperature down, and a low wind velocity along the soil surface, saves moisture that can be used by the crop.  Another benefit to a no-tillage system and heavy mat of residue is reduced competition from weed species, either broadleaf or grasses.  We see it consistently year after year when comparing our neighboring fields with either conventional tillage or high disturbance no-till.  Unfortunately, we still have to apply herbicides like everyone else.

Value of low disturbance Direct Seeding

I had the opportunity to compare a field with long term low disturbance direct seeding history with a bordering field having a 100+ year history using a conventional tillage system. 

The pic on the left represents the field with the 100+ history of tillage.  The pic below (middle) represents the field with a long history of low disturbance direct-seeding.  In 2020 both fields were in chemical fallow.  The field in the top pic was chem fallow on spring wheat stubble. and seeded with a high disturbance drill.  The field in the middle pic was chem fallow on spring canola stubble.  It was seeded with a low disturbance drill.

  Observation:  Both fields were thawed.   This condition followed 10 days of hard freeze that provided ice sufficient to skate on our pond.  A quick thaw followed.  The field (top pic) was squishy, wet underfoot.  The near-surface was well above field capacity for moisture.  My loafers were mucked some when walking over the field.   The field (middle pic) was firm, indicating water moved down into the profile leaving the near-surface soil near field capacity for moisture.  Along with the surface armor, there was no danger of mucking up my loafers anywhere in the field.  I could have driven my F150 over this field.    

     The pic to the left (bottom) shows a part of the same fied that has a long history of conventional tillage.  Shown is winter wheat stubble that is cut very short.  This field is likely to be chem fallowed in 2021 and seeded to winter wheat in the fall of 2021.  This stubble area is soft and mucky on the top 2" and frozen below 2", making it difficult to walk.  The recent 0.29" of moisture (snow/rain) that helped thaw the surface is held in that top 2".  I was able to compare this condition with a field on it's border with tall standing stubble that has a long history of low disturbance direct-seeding.  That field was thawed and firm underfoot indicating that the 0.29" of moisture (snow/rain) had moved deep into the soil profile leaving the surface firm and near field capacity for moisture.

     These field areas are close together and likely received the same weather, so what is making the difference in field conditions?   Two possibilities come to mind.

    1) there is no question that the soil structure is improved providing more porosity (lower bulk density) in the long term direct-seeded field compared to the long term conventionally tilled field.  The slake test would easily prove that; however, in winter, with freezing or frozen conditions, soil structure with more porosity isn't the full answer.  

    2) There has to be a temperature factor involved.  How does this factor in?  Well, --there is 34 years where our direct-seeded fields have reduced or eliminated erosion compared to conventionally tilled fields.   That's nearly a 1/3 of the time since native grass was removed from the landscape.  That time has to have an impact on soil organic matter loss (SOM).  Add to that, the time that SOM may have been building since 2010 with the introduction of our ultra-low disturbance no-till system, which includes the stripper-header, expanding our rotation to add more crop diversity, and beginning the introduction of cover crops.   My bet is that we have been able to improve our "soils health" to the point that we are getting more biological activity.  More biological activity results in more heat which in turn warms the ground resulting in faster frost melt, and along with increased porosity, allows moisture to enter deep into the soil profile drying down the surface soil to field capacity.

    I have yet to followup by doing some simple tests, and I have missed the timing for the temperature component of my theory.  My HOBO's should have been in the ground last fall and left until now.  There are several simple physical in-field tests that can be done now that indicates a comparison of bulk density and soil porosity.  I hope to get them done this spring/summer.

    

    
   

FARMING NATURES WAY

USDA is a great resource to start the process of improving soil health on the land we steward.

 

LETS BUILD HEALTHY SOILS (pt1of 2)

For the last 10 years our operation has been working on acquiring the capacity to build soil health.  We have needed knowledge on how to approach the subject, and the equipment to apply that knowledge.  Prior to 2010, we were working to stop the destruction of our soils.  We now have the pieces to improve our soils natural productivity and` make a serious attempt to reach our goal of a sustainable cropping system with reduced synthetic inputs. 

    How do we reach our goal?  My video and document search, along with our limited experience, shows that it is imperative that soil organic matter be increased.  I list several points, not necessarily prioritized, that I have found to be important.   1--manage our cropping system with an eye on ways to reduce herbicide, insecticide, and fungicide applications.   These all have components that negatively influence the development of soil organic matter.    2--we need to do minimal ground disturbance.  This minimizes soil structure damage, keeps roots intact to help hold soil in place and leave root and worm channels exposed at the soil surface.  This also minimizes loss of surface cover.  This also maximizes any mycorrhizal network we may be able to develop for a nutrient/moisture transport, and communication pathway between plants.   3--develop and maintain surface residue.  Residue protects the soil surface, reduces compaction from equipment, feeds the soil macrofauna along with some microfauna, and helps moderate the soil temperature.   4--minimize compaction.  This will help improve soil structure.  Compacted areas have poor soil structure and promote anaerobic soil conditions that increase the types of fungi and bacteria that cause plant diseases and insect predation.  Aerobic soil conditions, on the other hand, increase fungi and bacteria types that promote healthy soil organisms, and reduce pathogenic organisms that negatively impact plants     5--we need to change our fertilizer practices, to minimize the lowering of soil pH,  minimize harm to microbes, and reduce nutrient antagonism.   6--develop techniques to extend the time living roots are in the ground, --preferably all year long.    7--increase microbes and fungi, in our soil.  With our history of a monoculture wheat system, our soils are extremely bacterial.  Soils would perform better if the Bacteria to Fungi ratio was closer to 1/1.   Fungi are important to soil and plant health.  They convert nutrients into more plant available forms.  When available, mycorrhizea fungal networks are an important transporter of moisture and nutrients to plant roots.  Fungal mycellium serve as a line of defense for plant diseases.  Fungi can be promoted by doing all of the (1-6) points discussed above which boils down to, --providing fungi food for as much of the year as possible and stopping the destruction of their hyphae and mycelium.  The chart below shows the relationship between plant types and the bacteria to fungi ratio.  The chart shows there is not much on the "left" of our wheat monoculture other than weeds and rocks.

    For the past 2-3 years, I have participated with a group looking into soil and plant testing, organic forms of fertilizers, and ways to manipulate soil biology to increase soil health.  This has been a valuable experience, and there is more to learn.  

    During this time I have come to the conclusion that we can build healthy soils by proper crop management without amendments.  This requires absolute minimal tillage, keeping the soil surface covered, replacing chemical fallow with green fallow, diversifying our crop cultivars, extending the time we keep a living root in the ground, and paying attention to the synthetic inputs we apply to our crops so as to not destroy the positive gains we make from other practices employed.  The use of animals is not mandatory, but it has been shown that grazing animals speed up the positive soil health processes when properly managed.   

    I feel our operation has the equipment and basic knowledge to begin the process of building soil health.  We now need to develop management skills to make it all happen.  

    As a final note to this post:  Absolute minimal tillage by itself works well too stop erosion and establish a base from which to develop practices that will improve our soils natural productivity.  However, actual improvement of our soils natural productivity comes by managing soil biology through growing diverse plant cultivars.  The intensity, meaning the time with living roots in the ground, and the time taken to mitigate negative components to soil biology, such as synthetic amendments, sets the pace for improving our soils natural productive capacity.

Building Soil Resilience

 

  < Loyal to the Soil >     1:02:07

Above is the link to a presentation (3/3/2020) by a young progressive farmer, Derek Axten, about his journey of building soil health and a sustainable agriculture operation in the challenging environment of Minton, SK.  It's amazing to see what can be done in a relatively short time at a location with low rainfall, short season, on shallow soils with low infiltration.  Even though the Axten operation is a long way from St. John, WA, in an entirely different growing environment, I found several ideas that are food for thought. 

    Axten's operation centers around five principles:  Keeping the soil covered at all times, minimize soil disturbance, diversify plant species, keep a living root in the ground as long as possible, and incorporate livestock when possible.  The presentation tells their story of how they try to carry out those principles.  They also show ways they are adding value to the crops they raise.

    Their operation includes intercropping.  Flax and Chickpeas planted in alternate rows works well for them.  Flax and lentils work for them although others say this doesn't work.  Flax with another forb works.  Flax and mustard or canola works.  Flax and peas work and they don't have to be standup peas.  It's important that the crops mature fairly close together.  They don't normally add fertilizer with their interseeded crops except for a starter with micros.  They haven't found a companion crop that works well with their cereal crops.  They are doing some interseeding with a planter that seeds a companion when the grain is at flag to heading.  They are not finding a yield drag by going out to 15" with the planter, and also, with singulation, they have cut seed rates back giving a substantial cost saving.

Succeed with No-Till

 < Dwayne Beck presentation>    55:34

In recent years I have observed a number of no-till operations that do not look as if the operators understand that there are some basic fundamentals that need to be followed to be successful.  I fear these operations will get into trouble, or revert back to their comfortable position with tillage.  I recommend and encourage farmers to open the above link and learn from it.

This image of Dwayne Beck, a researcher at the Dakota Lakes Research Farm near Pierre, SD, is from a presentation he gave at a meeting sponsored by the SD NO-TILL ASSOCIATION, March 11, 2019.  I have had the privilege of meeting with him and listening to several presentations over the years, starting in May of 1995 at the Dakota Lakes Research Farm.  I would say that Dwayne is the GURU of gurus when it comes to no-till.  Back in the early 1990s, he established the basic fundamentals for successfully no-tilling and the reasoning behind them.  His interest and mine are the same,  --manage water better.  He needed to stop soil erosion in SD, and I needed to stop soil erosion on my operation.  No-tilling was key to that goal.  Unlike so much information available through media, his basic fundamentals on Sanitation, Diversity, Intensity and Competition to successfully no-till works anywhere on the globe.   My first trip (1995) to the research station was prompted by complaints I had using Glyphosate for weed control.  My second trip was prompted by complaints I had about applying his fundamentals to my operation.  The take-home message from that trip was his statement to me, "I earned my Ph.D. developing those fundamentals, now, you will earn your Ph.D. learning how to apply those fundamentals on your farm".  He was so right!  I knew back then that everything about farming is site-specific, but didn't think about it in this context.  Soils, microclimates, topography vary across the land.  I was trying to clone his Pierre SD practices for St. John WA, and that didn't work.  When I adapted my practices to fit the FUNDAMENTALS, no-tilling did work.  We learn our trade and tend to get stuck in our ways instead of adapting to changing conditions.  Climate change and an increasing population with its political fall out are major challenges for farming, and will be more so in the future.  As we move forward to a goal of sustainable production and more nutrient-dense foods with reduced commercial inputs we will have to follow "improved" fundamentals.  Unfortunately, I don't know how to interpret "improved fundamentals" at this time, but I do have a blurred direction to follow.

RUSLE2 -- Explanation of Use

RUSLE2 is used by USDA to evaluate a farm operation for various programs offered by the USDA.  It also can be used by individuals to evaluate practices for the purpose of improving soil health.  Following, is the link to this 1:03:34 presentation explaining the variables that make up  RUSLE2.  [ RUSLE2 explained ]   This is a very good and thorough understandable explanation of what goes into the evaluation.  It's a much better tool than I ever thought.  I knew that it was under constant research to improve its accuracy.