Agronomics101

Follow Up on the recent post dealing with 6 items of Compaction

Digging to give you the best information regarding soils as I know how.

Recently I wrote some important points to consider when you are dealing with compaction not only in the fall but the springtime.  I have been chasing issues growers have found to be pesky and reoccurring since the era of 1981.  I am here to tell you I have caught up with soil compaction and have been able to spot it from a highway at 65mph. Sometimes it is whoa and stop to get out, walk across a fence and stick a probe or spade in the ground to see what is the intensity of the problem.  If the grower stops by we get into a great conversation almost everytime.

So I am reading this article in the Indiana Prairie Farmer which I am going to quote from what this man David Nanda says. He is director of genetics for Seed Genetics Direct, sponsor of Corn Watch ’20.

The article begins by Tom Bechman: Dave Nanda insisted on this picture showing the remnants of boot prints in the Corn Watch ’20 field in August. This year we implemented an emergence plot to study differences in corn plants based on when they emerge. The boot prints were made when I placed flags in muddy soil after a heavy rain on the first day corn decided to emerge. If the first plants aren’t flagged when they emerge, it defeats the purpose of tracking emergence until all plants come up.

They were 6 inches deep in a few places, and they’re still hefty prints,” Nanda says. He is director of genetics for Seed Genetics Direct.

I wanted to document that they were still there in August because it shows that once soil is compacted, the compaction doesn’t go away quickly,” Nanda says. “And it doesn’t matter if soil compaction is created by a 250-pound man or a tractor weighing 10 tons or the planter disc forming the sidewall. Once it’s there, the impact on the soil can continue for a long time.”

I, Mike Petersen, have been saying for nigh on 40 years what comes next from this person Dave Nanda.

As long as there is ample moisture, the soil compaction won’t likely impact those plants more than it already has during early-season stress,” Nanda says. “Visible differences might occur if it turns dry again.”  How-em-ever folks, too many farmers in the latitudes north of the 38th degree parallel feel that the soils will freeze and thaw a few times and all will be fine.  Oh brother where art though? To quote a funny movie from a few years back…  No such thing.  We are wanting more power to pull large disk-rippers (400 to 620hp tractors), 1000 to 1500 bushel grain carts, silage trucks for those who cut big semi-loads of corn silage, 13 shank subsoil tools, big red, blue or green disk-chisel implements over 35 ft wide and go 6 mph with bounce in too moist of soils and install compaction. Or, those 36 to 48 row planters when soil conditions are wet and the thought process “we gotta go”.  Oh my!  Do I understand? Yes, Maybe and then No.

Tom Bechman writes further into the article; “When soil compaction was first recognized as an issue in the 1980s, many people assumed that freeze and thaw cycles would correct it over time. The same university studies indicate that while these cycles can eventually help break down compacted layers, they typically don’t help as quickly or as much as most people originally suspected. Even in locations where there are normally several freeze and thaw cycles during the winter, soil compaction can persist over time.”  I am quite pleased to see this article written and to bring a portion of it to you.  You can go on-line and read it via this hyperlink — https://www.farmprogress.com/corn/soil-compaction-created-year-wont-just-disappear?NL=SO-09&Issue=SO-09_20200905_SO-09_172&sfvc4enews=42&cl=article_1_b&utm_rid=CPG02000003629899&utm_campaign=52706&utm_medium=email&elq2=5f2e21bc2d1842acb0f6653c5988cd9e

I am glad to hear others saying this.  Standout researchers up north near Morris, Minnesota – yes that is cold Minnesota where it freezes up tight many winters – stated it takes 14 cycles of freeze-thaw to break compaction up by ice crystals and wedges.  But folks, that may happen only in the surface two inches (5 cm).  What about 7 to 11 inches deep?  Once for the total thaw-out.

What I am suggesting here?  When you see ragged ups and downs in your corn or soybean heights, or intervals of tracks early on where the corn is stunted or discolored with purple tinted leaves or later two rows spaced 60 to 90 inches apart that are shorter, smaller leafed and roll in the midday sun – the 800 pound compaction gorilla has come to stay.  Do check it out, see how extensive it is, is it in the entire field of just on the turn row ends?  How deep and thick?  Right now with fall harvest time in front of you the proof will be in the combine and trailer to haul it to market.  Watch your mapping tools of that screen in your combine and the results of the yields – it will be evident or not.

We at Orthman Manufacturing study the compaction issue; because we have a lineup of Territory Rep’s to explain and digest the conditions, we can help you wade into what comes next in the alleviation of soil compaction.  Do not just go get the subsoil tool and go to ripping the silly out of every acre at 15 inches deep – please!  Call or contact me if you like.  As a scientist that has been in the soil trenches and digging about in about every state of the Union I am happy to offer clues and suggestions.  Do not hesitate to go to the tab CONTACT US on the home page of this site and visit with any of us.

Orthman-McNaught Farm Update

With soybean harvest into full swing in Nebraska and states all across the Corn Belt we are very pleased with the results of this years soybeans.  They were strip tilled 10 days prior to planting and then planted on April 29th, 2020.  With the abundant amount of sunshine this years, our soybeans that Pat McNaught nurtured with four irrigation events, the month of August continued to bless east Central Nebraska with sunlight and not scorching heat – the beans did well.  This year we followed our own advice as well as our advisor John from Nutrien to spray as a foliar application of a slow release nitrogen, fungicide and a ‘secret sauce’ that spurred at R3 pod set like few have seen before. Thousands of the plants put on 5 to 7 pods per node on the last couple of nodes high up in the plants architecture.  We were pleasantly surprised and pleased.

The good folks from AKRS John Deere helped with the Orthman Soybean harvest this year

Our lowest yield was 77.7bu/ac. and it went up from there. Highest was 93.5bu/acre with an overall average of the field where the plots were was  83.3bu/acre.  Moisture averaged 12.1%.  The root system under these beans was nothing short of superb with laterals going out to 9-12 inches on either side of the main taproot.  The taproot sank itself over 38 inches deep which for beans in this part of the world that is exceptional.  We planted 2.3 to 2.8 soybeans for you that are asking with the 2.8’s tipping the mark at 93.5bu/acre.  All accomplished September 23rd.

I attribute the beans doing so well as we had employed the Orthman 1tRIPr to set the stage for a big root system, good water management with Pat getting to the first water earlier than so many folks surrounding his farm and monitoring the soil moisture conditions.  Treating soybeans like the buck-toothed, redhead stepchild of a wild person was not our plans.  They responded well to good management and the late foliar application.  Next year weather permitting Pat says look out 100 bu/acre ceiling, we will shatter you.

So now it is a game of patience for all of us at Orthman and the McNaught family to stick the snout of the 8row Deere combine head in the field and get after our plots and bulk corn.  We will keep you informed of the results here on PrecisionTillage.com and also the Orthman FaceBook page.

May you all have a happy and bountiful harvest this October.

Is Compaction More of Just a Pest OR Does it Have Lingering Ramifications?

That question (in the title) was posed to me from a younger grower while I was with my co-worker up in NW Minnesota during the week of September 9th at a field event put on by University of Minnesota Extension Service to show folks and go over with growers speaking at the study near Barrett, MN focused around Soil Health and Tillage.

I have been away from the computer for a few days with field events, traveling by pickup to and from and a bicycling vacation in the mountains of Southern Wyoming which was for me was incredible fun as we traveled on an 100+ year old abandoned railway carved in the mountains to transport, coal and lumber in the 1930’s up until the 1950’s.  A portion of the trail has been improved for horses, people to walk and bicycles to ride on.  We also rode on a portion that will be developed in the future riding under fallen trees, over logs, over rocks, around shrubs and through tall grasses – oh a great adventure on Adventure bicycles/Mountain bikes.  So let us dig into this posed question….

This year, 2020, was the second year we have conducted some specific soil compaction measurements and analysis in numerous field from east central Nebraska to the Front Range of Colorado and fields in between for the purpose to relate to our readers and customers differences in soil density under strip till, No-Till and Conventional Till. We measured trafficked rows, non-trafficked rows and what one would find directly under where the seed was placed this spring.  As a tillage company why would we see a reason to do this?  For those of you who know Mike Petersen the answer is obvious but to others, well here are six thoughts to think upon.

I am not going to blow smoke up the seams of your britches – compaction has caused many detrimental effects to the growth of crop root systems whether we farm light, medium or heavy textured soils [sandy to loam or silt loams to silty clays.  Walk with me to consider each one by one I have selected six items:

1)   Water movement, in and down a soil below the 20 inch (50cm) depth will be slowed dramatically with soil compaction.
Compacted soils have been squeezed, squished, mauled, smeared and run over so many times with full width tillage passes, heavy harvest traffic, big disks, twisted shanks on chisel frames, sweep plows, moldboard plows, and even big planters when soils are too moist – a shame our soils even respond whatsoever to additions of fertility.

FIG 1:    Illustration of gas exchange in soils

2)   Gaseous exchange in and out of the soil.  This includes Oxygen, carbon dioxide, carbon monoxide, sulfur dioxide, nitrous oxide, argon, and many more.  These gases are part of the biological cycles of the roots respiring and transpiring in the soil as well as the microbial life living, breathing and dying.  Macro and microorthopods living in the soil and the breakdown of carbonaceous materials from previous crops chemically and biochemically.  Some of these gases are absorbed by roots as well as the fungi, earthworms and plant roots.  In a chemical combination with water we can get sulfuric acids, carbonic acid, malic acid, humic acids, fulvic acid, weak nitric acids that all aid in the breakdown of carbon materials and maintaining the pH balance for soil life.  The informative diagram to the right offers an idea how all this occurs with gases in soils, through plant life and effect on the carbon cycle. Where I am going with this thought process is that when soils are far too dense the respiration and invasion of CO2 is dramatically impacted; slowing root growth, uptake of water and other nutrients, even evaporation is slowed and other gases that should move in and out of the soil are affected.  If a number of the gases are slowed the soil chemistry balance goes to use a word – kerflooey!

3)   Biologic activity;  this is an entire text book if I was to delve into the subject.  However, soil biology – lifecycles of microbes, the activity of fungi, insects living in the soil, earthworms living, populating and cycling materials, nematodes, colembra, spiders, crickets, etc  they all can and are negatively impacted with soil compacted layers.  When pore space is diminished and squeezed down to near nothing – O2 is lost and the aerobic bacteria which are the most important species in the upper 20 inches of the soil to convert carbon based materials and mineral fertilizers to be available to the plant root.  Also with reduced pore space we see water availability and the microbial life diminish greatly. The soil holds tightly onto the water molecules and the roots matrix potential [MP] or sucking power to simplify the MP term, just cannot pull the water into the root.  Result — drought-like stress.

4)   Root development, both vertical and lateral growth in soils that are compacted is negatively effected. When roots of all crops we raise for food, fiber or forage are new from the seed they have very small amounts of energy and force to extend root tips.  When they encounter resistive forces much higher then what the root tip can push down or forward and these roots struggle to keep going – growth is retarded, too much energy is used and the plant goes into stress and slows down growth, uptake of water and nutrients is damaged and the plant in a fashion goes backwards.  It has been said that with every 1/2 inch of lateral growth as seen in Figure 2 yield drop off can be 1

5)   Accumulation or Loses of of organic carbon.    Compacted soils, how does that impose problems on soil organic carbon gains or loss you ask?
The carbon based materials remaining on the soil surface and a layer of compaction lies below let us say starting at 4 inches extending to 7 inches deep.  Soils above the compacted layer will rise in temperature faster and carbon based fibers will oxidize faster than a soil that breathes better and allows water to move downward.  Microbes will eat the near surface material quicker because they have difficulty in repopulation and moving down with water that follows cracks, ped faces, worm tunnels and contiguous pores.  When they eat all what is in the near surface and it oxidizes away then again the young plants can be in trouble.

Early root growth encountering compaction – Source FAO

6)   Heat exchange
        I just started on the idea of how soils will heat up in the early days of growth, especially in conventional full width tillage systems.   I will try to explain it; structurally, a higher organic matter content in the soil surface area increases soil porosity which also decreases soil thermal conductivity and which thermal diffusivity, which is a is key parameter that describes the rate at which soil temperature changes given a temperature gradient (one dimension of Fourier’s Law in Physics). This thermal diffusivity value of D is determined by soil composition (minerals, air, water/ice, organic matter) and soil structure.  When soil pores are filled with air or nearly dry, the diffusivity is higher.  As a result, soil organic matter (SOM) will act as an insulator and the presence of SOM cools the soil during spring and summer, while its warming effect during winter is less important due to the insulating snow cover.  Opposite – low organic matter soils and compacted will respond differently and any soil organic matter can and will be burned up.  There have been a good deal of studies in the permafrost region of the      Northern Latitudes that verify this but in frozen soils.

In all of the years of over tilling soils, rice paddies of SE Asia or China, the terraces of the Danube River in Europe, the soil biological life has been overwhelmed to the point some species have had their population decimated that their one time effectiveness and importance is nearly obliterated.  Structural soil units of the soil complex responds as if it is exhausted now portraying soil erosion rates > 10T/acre [22.4T/ha].  We have observed severely eroded upper positioned soils on the landscape more conducive to erosion and continue to erode when compaction is involved.  This is part of the reasoning behind our work to study, maintain a current view of tillage systems and what tillage is doing and crop responses.  We want to know what our Strip Till implement does, how soils respond and how crops respond even more, as well water movement, organic matter use and storage on the surface and down into the soil profile.  The most biological active zone of the soil is the the surface 4 to 6 inches, when that erodes away – we are in for a bumpy ride.

I personally have been digging  soil pits to observe roots but also considered soil profile building or soil deterioration for over 39 years which a soils man like me really takes this serious.  Since 1984 I have noted and documented over 1700 soil pits to better understand tillage or the lack of.  What we do when the 1tRIPr goes out the big doors at Lexington, Nebraska manufacturing plant; is to provide our customer an assurance that we have placed our best knowledge and skills building this implement with organized science in and behind the toolbar, down to the points on the shanks, yes the wavy coulters close behind that shank, the baskets, how fast or slow it is pulled through the soils.  That is why we are doing research, poking in and around fields.  I do realize that I want to know more, for I for sure have not arrived.  We are welding and manufacturing a machine the builds the best initial rootzone, we see the 1tRIPr that conditions the soil for plant-root development all season long and offer a positive and accurate placement of grower chosen fertility.  How our tool tills to help maintain vertical soil structural units is very important to water movement, we aim to reduce the potential for soil erosivity, we attempt to work during the periods of the soil biological activity slowed so bio-damage is minimized and tilled at the right soil moisture conditions to do the proper job under and into the zones of compaction.

I hope this makes sense that Strip Till is making a difference for the grower’s checking account and helping the soils to function properly.  I welcome questions shot across the bow of what I write.  Glad to offer help if I can and show or inform you what we are learning.

I am available by email: mpetersen@orthman.com

 

Important Root Features

As I have been tasked to dig some deep holes in order to observe roots for purposes of what type, how deep and water availability profiles of some specific corn breeding types this summer, I got to thinking that a number of you reading may be interested in what the real important features of a root system.  Let me write what a few of those are as we are now into the last days of the fruiting bodies doing their thing before dry-down.  For those of you in the northern latitudes with it being latter days of summer we are seeing corn dent in places, soybeans filling the last pods up high in the plant architecture, dry edibles starting to turn yellow and beans in the pods firm, the nuts of the sunflowers and shells are hardening, and cotton is in later segment of boll filling.

Cross section (100X magnification) of a corn root

First basic premise of roots – anchoring the plant above ground structures (stems, leaves, nodes, branches and fruiting bodies).  This root system whether monocots (grassy plants) or dicots (broadleafs), roots hold the plant upright like feet of man.
More importantly is the next topic…. the specific cells of the maize root comes in specific sections of the younger root tip area to the older tissues nearer to the stem that moves materials up and into the leaves.  As depicted in the image in black off to the right, the epidermis cells are like our skin to keep the cortex cells hydrated to hold water, sugars, proteins, hormones. and conductive tissues named xylem, phloem and Metaxylem inside.  Many of the cortex cells (as what you can see in the diagram off to the right) hold water to maintain plant turgidity and cellular metabolites for the lateral roots and hair roots to grow.  The metaxylem cells are the large tubes for water, sugars and other metabolites for upward flow.  The phloem tissues return products from the leaves downward along with hormone messages.  Near the phloem tubes are phloem packets in a corn plant where specific metabolites are held during all phases of photosynthesis and keep the so called “engine” running 24/7.  The endodermis is exclusive to roots, and serves as a checkpoint or gateway for materials entering the root’s vascular system from outside the root such as from bacteria living and dying on the root epidermis.  Entry of nutrients such as N, P, Zn and S via mycorrhizae  come into the root by the way of specific structures called hyphae.  Please take a look at the image of hyphae of VAM (vascular arbuscular mycorrhizae) below.  I am just showing this for this time and will go into more detail about mycorrhizae at a later time.

As I wrote in the very beginning about root investigations I have done this summer… with a past seasoned agronomist who worked many years for Monsanto we looked at roots that had root expansion that grew deep as the plants were in height above ground.  We did the volumetric measurements of the root-to-soil interactive zone and the root systems expanded up to 5800 cubic inches in the soil below each plant of the better root developed hybrids.  What that gives a plant in medium textured soils (sil, sicl, scl, loams) about 5.8 gallons of water to hydrate and feed those individual plants.  That is at tassle time all the way up through the reproductive stages and beyond milk stage of the kernels a tremendous resource to finish all the kernels on the cob.  With irrigation a grower can produce heavy weight corn up to 63lbs per bushel.  Yes that depends upon kernel size, however fed and watered by irrigation or the clouds, corn producers who grow today’s corn hybrids with larger root systems will do great when the combine pulls into the field.

What does that have to do with Strip Till and this website blog?  Starting off the plant right with nutrition placed where the soil has been tilled in a specific zone goes a long way in setting the potential for big corn yields.  Selection of a great rooting hybrid, nutrients right in the pathway of the root growth, residue to cool and blanket the soil for a portion of the growing period, residues to provide the carbon sources for the microbes, worms and other invertebrates who live in the soil – all working in harmony with a strip till system makes tons of sense and provides the environment for a corn plant to thrive.  It means the world to us at Orthman how we are providing said environment with strip tillage via the 1tRIPr.  You have more questions please get in touch with me or any of our guys as Territory Managers around the country.  Their contact information is on this website and any of us would enjoy a conversation either by phone or email.

Harvest is around the corner and we look forward to it.  May September be calmer, less wind, please some rain for those of us who live out west and no Hail!  More to come folks as we look forward.

The Orthman Event for Summer of 2020 – Check it Out!

We at Orthman Manufacturing are happy to announce we have a date for you to come to the Orthman Research Farm near Polk, Nebraska north of State Hwy 66.  Please click on the link below in red and see what the timing is for August 26th starting around 1:00pm CDT.  However do note… we are asking people to park near the High School in Polk, Nebraska and we will bus to the site east and north of the village of Polk.  Reason being there is very little parking on the county road and it would be unsafe.  We will transport all who come via good school buses to and back to the cars.  Our suggestion on the 26th of August would be to arrive at the school around 12:00 Noon to 12:30pm and meet some neighbors and others as you come to learn about Strip Till and a Smart Precision Based fertility systems approach in irrigated corn.

The link will send you to YouTube to see and hear about the day we have put together.  The link is right here, do enjoy and come for a August afternoon to see how Orthman with great partners in John Deere, SureFire Ag, North Forty Seed Company (Pioneer Seeds), and Nutrien all worked together this spring and summer to develop data and a very good corn crop. which we are pleased with.  This should be an educational afternoon, some cold non-alcoholic refreshments to keep you all hydrated and thinking straight.    It is about 3 minutes in length, please listen and enjoy.     https://youtu.be/aiFfFoRQZm8   

We look forward to seeing many folks come to hear how roots influence the story of growing corn with a solid seed selection from Pioneer and their Agronomic people, a soil pit with our own soils man, Mike Petersen in a root/soils pit to describe what occurred and what we do with a good fertility program along with John Person with Nutrien of why this program was an aggressive one but very smart.  SureFire Ag will be explaining the precision based nutrient delivery system used on the planter and strip till rig – all important to the systems approach.  We want all who are feeling good to come.  Your brain will be challenged but filled too at the same time.  Safe distancing is very possible where we are at.  See you there!!

A product of plant chemistry that dictates what happens in plant root systems

Agronomic sciences have advanced a long ways in the last 5 years which pleases me.  Nigh on 40 years ago this fall I worked in a backhoe pit along side a good friend and Technician for one of the Soil Conservation District field offices (now USDA-NRCS) in eastern Colorado to study and determine why an irrigated corn crop was doing so poorly – we were looking at roots and if compaction was the ugly culprit.  For sure it is not like yesterday but I remember working with this man on several hundred soil-root pits until his retirement and later passing on.  Kudos to you Marv for getting me into this dimension of the soil science profession.  Why do I mention this?  A highly regarded scientist from back in the eastern Corn Belt wrote recently about the importance of cytokinins, roots, root tips and the value of these phytohormones.

The basic molecule rings of a cytokinin. Organic Chemistry comes to light.

John Kempf, writes a daily blog that detailed a few words I would like you to read, “Cytokinins are produced in growing root tips and cobalt is a key enzyme cofactor needed for cytokinin synthesis.  The key is that a growing root tip is needed to produce cytokinins, particularly at the stages of bud initation and pollination.

A healthy disease resistant plant will always be cytokinin dominant, rather than auxin dominant. This means they will always have more growing root tips (producing cytokinins) than they have growing shoot tips or seeds (producing auxins). It also means that these plants will have larger root biomass than vegetative biomass. Cytokinins are produced in growing root tips and cobalt is a key enzyme cofactor needed for cytokinin synthesis. The key is that a growing root tip is needed to produce cytokinins, particularly at the stages of bud initation and pollination. A healthy disease resistant plant will always be cytokinin dominant, rather than auxin dominant. This means they will always have more growing root tips (producing cytokinins) than they have growing shoot tips or seeds (producing auxins). It also means that these plants will have larger root biomass than vegetative biomass.”  He goes on to speak about plants such as edible beans and soybeans are quite dependent upon cytokinins to produce many pods and healthy beans.

Allow me to expand for a moment, having healthy roots, thousands of square inches of soil infiltrated by roots, root hairs and root tips will produce a lot of this phytohormone to stimulate photosynthesis and sugar production, move nutrients up the xylem tissues to the leaves and keep the cycle of plant life going all season until senescence in nearly all if not all crops farmers grow.  To tell you what I have measured in root pits and explored with others the under-the-surface hidden world of roots would be a long conversation – I am saying that Dr. Kempf just tapped the upper part of the iceberg with this and I hope he writes more on the subject.

In my 1700+ root pits since that first one with Marv back in 1981 exposed for a farmer I have measured root lengths, root density, root penetration, counted linear inches of even the smallest roots, photographed roots, invested 8-9 hours in a soil pit to get the facts.  I have read numbers and numbers of scientific journal articles about roots, own texts about roots and so on and so on.  Well that is nice you are weird Mike.  No, it is this part of soil science that resonates with me for me to really know why the plant does what it does in a growing season, it is why I find some corn varieties excel where others flop-fizzle, why knowing that compaction is the number 1 limitation for top root development, cytokinin expression and best yield outcomes.  When we get down to it, knowing how plants move nutrients, absorb and move water, utilize phytohormones that sense details of the soil environment to aid crop development – Wow!

We at Orthman Manufacturing have a good understanding of compaction and soil resistance and what kinds of tools farmers need to combat this problem that plagues growers not only in conventional tillage systems, yes you folks with No-Till are not immune to it and even growers who routinely strip till are aware of the compaction culprit.  We study it, we talk about it and then provide solutions at Orthman.  As we do we are learning more about what goes on in the root system down to the xylem tissues so we can be an informed resource to growers all over the globe.  Folks it is not just selling iron, we are offering tools that are steel but also tools that go into your mental toolbox to give you more in the harvest truck that goes to market.  Get in touch with us today.

Sidedress Fertilization Is it only Nitrogen you should be applying?

Good question for all of you that are getting after the duty of sidedressing or fertigating now that the corn is climbing towards the sky like in the story of “Jack and the Beanstalk”.  The demand from corn plants DNA signals is about to “hit the gas” on N consumption.  You all are aware of that whether you are a rainfed farmer or an irrigated farmer, but what about potassium, zinc, sulfur and even phosphorus?  Have you sampled with plant tissues to get an up-to-date view of how the plant stands with existing soil conditions and what you fed it earlier?  Yes there is a cost to that, yet folks in the days we sit in with low commodity prices a full awareness of your crops nutrition has much value to fall time results.  Sure we want to get by and hope for the best.  I get that, but even though prices look pitiful would you stop feeding that hungry teenager who fades 20 minutes after lunch and looks like he will gnaw on your arm while you haul gated pipe off the trailer and onto the ground and shove them together?  Inside joke I know for the rainfed grower in Iowa, Illinois, Indiana or other states that have not irrigated with 8 inch pipe.  Just the same folks, we do not stop feeding a crop.  Having a good idea where one stands sets the stage for the hybrids of today to do well or just so-so.

We at Orthman have teamed up with some great partners to study what happens to resurrect a farm that was less than optimally treated for some time nutritionally, old traditions of dosing with big amounts of N up front and little or nothing throughout the season was the game plan.  We soil sampled before we strip tilled and placed nutrition and the soils were quite depleted, that literally made me gasp some.  All that is to say now we have tissue sampled and found with the soils just warming into the temperature range in the upper 10 inches for the microbes to assimilate, populate and release nutrients as well as the early root system proliferate the soil profile.  We are still a bit shy of what should be a sufficient to adequate level but we are responding with two sidedress operations.

Applying liquid products with Orthman cultivator during sidedress and ditching process.

Soil temperatures last week (1st week of June) were touching 70 degrees F. at 8-9 inches below the surface.  That says what to you reading this?  A large cross section of the microbial population is getting into the mode of working, eating, populating, dying and cycling.  The nutritional products we laid in at 6.5 inches is right in that zone where we observed the 70°F are poised to and is being utilized and made available in the form most readily taken up by the young root system.  Those old decaying roots are food for the bacteria, earthworms, other microorthopods, spiders, and such to breakdown organic carbonaceous materials, unlocking nutrients.  All that being said, now is the time to supply N to feed the microbes but not over-feed them to take the crop towards its fruiting stage and kernel set.

In the field these last two weeks I have observed yellow striping in the corn at V3-V5.  It is not zinc but sulfur for many plants.  Sulfur as I have written on this blog plays a key role in photosynthesis and protein movement within the plant.  May I suggest you get out and take a close look in your fields and before you finish every field in the sidedressing with 32% or 28% or even anyhydrous – to evaluate for sulfur needs.  From here at the V4-V6 stage to V10 the call for sulfur is not huge but quite apparent to top production.  You purchased >$300 bag corn, please be wise about how sulfur is critical to what the rapidly growing plant needs.

Yes Nitrogen is needed; please take into consideration the important secondary nutrient – S.  We at Orthman also realize that many of you are using cultivators. Truly, a super time to place some of your total N and S fertility program — up-close and personal to the growing crop.  As you do the plant will very likely respond within 2 to 4 days with a color change and growth.  As it does the on-off switches inside the xylem and phloem tissues go on!  Cultivating not only for pesky weeds, the feeding of the hungry teenager makes for a better ending to the last part of the yield game plan.  I don’t know very many of us that walk away from well earned , hard fought and planned victory in the fourth quarter without a big smile.  A story of the fourth quarter success:  A tough quarterback in a post season game behind by six in the last few minutes with the ball on 6 or 7 yard line said “we’ve got ‘em right where we want ‘em”.  He marched the team 94 yards and crossed the goal line for a touchdown and a win, later a Super Bowl ring.  Some may remember that team.

You got ‘em right where you want those plants.

Some of the Latest Field Research on Soil Compaction – 10 Years No-Till to 11 Years Strip Till

It comes to you hot from the fields with growing corn at the V4 stage.  In East Central Nebraska my cohort Pat McNaught and I have been digging up in between corn rows and right in the row where the present crop is growing and taking soil resistance measurements to follow up with the 2019 project and learn even more of what is happening below ground.  This year we were able to get to a long term No-Till field and then same vintage of Strip-Till duration.

In the chart below you can observe in the soft row what the soil condition is like.  Pat and I dug this five days after the 4+ inch rain in late May.  The corn in both fields was V4 to V5 stage and not under any stress, the soil moisture condition was 75-80% of field capacity at 6 inches and 85% at 12 inches.  The lateral (side-to-side) soil resistance values in the soft row is significantly less in the Strip Till ground.  In the upper 5 inches of the soil profile the vertical soil resistance is less dense than the No-Till.  As we observed these two fields within 7 miles of one another, two very dedicated farmers to their systems and very good corn production 250-295 bushels per acre yields (irrigated), we observed the root systems, both were starting the second set of nodal roots. The big difference was the Strip Tilled corn was 23 inches deep and the No-Till was 16 inches.

We are not casting stones here, but you get to look at some differences in how a No-Till field stacks up to a long term Orthman 1tRIPr Strip-Till field.

We will be monitoring these fields as the season progresses.  As of this early part of June all systems are go to hit a top notch yield.

 

Sulfur one of the secondary nutrients in crops carries out some very important functions in the plant growth cycle from early emergence to starch fill in grain.  Even though it is pretty well known that sulfur (S) is mobile in the soil, it is not in a plant’s vascular system – the lower sets of leaves will not show deficiencies of S as much as the upper/newer leaves will depict a yellowing appearance.  Do not misdiagnose that yellowing a lack of nitrogen (N), if that happens folks tend to think more N will solve it – no sir, usually creates more of a sulfur problem especially late in the crop’s life cycle.  Sulfur does not transfer from older growth into the new leaves.  With reason then late applications of S when diagnosed properly can be a great help in yield and plant-grain function.  Usually a foliar and soil feeding will do the trick.

What is the function of S in the plant?

Dan Davidson who I have known for more than 15 years, writing for the Illinois Soybean Growers, reports that sulfur and nitrogen work complimentary to one another. Sulfur is a component of specific amino acids in the photosynthesis processes and seed production: methionine, cysteine and cystine.

He went on to say; “Sulfur is a component of numerous enzymes (proteins) that regulate photosynthesis and nitrogen fixation and assimilation by the plant. It’s a component of ferredoxin, an iron-sulfur protein found in the chloroplasts—the site of photosynthesis. Ferredoxin also plays a metabolic role in both nitrogen fixation and sulfate reduction and the assimilation of nitrogen by rhizobacteria living in the nodules in soybeans”.

Early season sulfur deficiency, V5 stage

One of the important enzymes that drive nitrogen fixation is nitrogenase. This enzyme contains considerable amounts of sulfur and converts atmospheric nitrogen to ammonia. In addition Ferredoxin acts as an electron transfer agent in both nitrogen fixation and nitrogen assimilation into protein found in legume production like soybeans.

When does sulfur become available via the microbial breakdown of the organic sulfur components in soils organic matter (SOM)?

The activation of S is very dependent upon soil temperature and soil moisture.  Both air and soil temperature below 50°F (10°C) is very minimal.  Oxidation of the SOM really kicks in gear between 75-85°F [23-29°C] which says this importance nutrient for photosynthesis production, enzymes, and proteins is not happening in the upper 8 inches of the soil profile until early to mid-June in the Northern hemisphere.  A short list of who in the soil (bacteria) that oxidize S to become Sulfate (SO4) for the plant to utilize it directly: Chlorodium spp., Chlymydiaceae spp., Cytophaga spp., Flavobacterium spp., Porphytomonas spp., Prosthecobacter spp., Rubritaleaceae spp., Bacteriodes spp., Candidatus spp., Chthoniobacteria spp., and Fucophilus spp.  As I indicate with the spp, we are looking at multiple species within the two genuses of Chlymydiaceae and Candidatus for instance.  Please I am not trying to slap a big number of genus and species names to tie your tongue and sound like I am so smart with microbiology.  The number of bacteria in the soils both anaerobically and aerobically is large and their function oxidizes carbon rich compounds in residues and SOM and provides Sulfates available to the plant root.  For example; most obvious to anyone who has dug around in a mucky soil near a cattail mud hole know about the sulfidic odor [hydrogen sulfide] that on a hot summer day can make you nearly gag – those are anaerobic bacteria – some 23 genera, 220 species are known of the Deltaproteobacteria order; the second most is in the facultative-anaerobes of Firmicutes.  All in all these bacteria are important to take SOM and make SO4 available to a plant.

Therefore an important point to make here, sulfur coming available via bacteria in the soil and some mycorrhizae does not start right off the bat.  The need of sulfur within the first 40 days after emergence is high and we can help that hungry growing plant function better and improve yield potential by adding S via the spring pre-plant and in the starter products. Couple of examples: Soybeans remove 1.7-2.0 lbs. per 10 bushels of grain at a 60 bu/ac yield or 10-12 lbs/acre in a season, then corn removes 0.5lb per 10 bushels of grain or requires 30-35lbs/acre in a season.  Of those noted needs sulfur from V10 to hard doe stage R3-R4 in corn is over 60% of the plants total requirement of sulfur.  The soils are at their maximum of temperature extension at V14-R1 into the soil profile.  Soil temperature in the upper 10 inches (25cm) is reaching even under full canopy 85-88°F [29-31°C] and the soil bacteria are turning over nutrients in the SOM every hour of the day.

Sulfur deficiency in soybeans

In continuous corn fields the amount of S in the residues is not that great so a smart/wise nutrient management plan begins in a strip till system right as one strip tills to planting time and then during the rest of the season.  We here at Orthman advocate tissue sampling to best identify what is happening in the growing crop.  From information back in 2017 from a Purdue University Soil Fertility Update, the good folks at Purdue suggested;  In the plant, S is a component of two amino acids and occurs in protein in a ratio of 1 part S to about 15 parts N. Therefore, the N:S ratio of plant tissue as well as the S concentration are used to identify S deficiency. The lower the S concentration and the higher the N:S ratio the more likely S is deficient in the plant. Tissues from corn as you look at sulfur less than 0.15% and N:S ratio greater than 20:1 are most likely S deficient. Sulfur is most likely adequate when corn tissue S is greater than 0.20% and the N:S ratio is less than 12:1. Tissue S and N:S values in between these levels can go either way – deficient or adequate. Critical tissue S levels for soybean have been studied much less than for corn. Typically 0.2-0.3% S is considered adequate.  This kind of information can really be helpful in determining the S health of your plants and what to do about it.

Knowing that a good amount of sulfur prior to 2007 came from atmospheric deposition, mainly from coal-fire generating plants.  Good scrubbing techniques of the exhaust stacks have changed that but our plants have lost that input.  In fact there are power plants that offer the cleanings as a fertility source of sulfur for very little money per ton.  Higher yielding hybrids have shown us the demand for S, so we must watch our all-season nutrient program.  It is our belief to bring this up before your eyes and know that Orthman is capable of helping your deliver nutrients to your crops via the 1tRIPr, cultivators, and in-crop fertilizer soil insertion applicators.

Stay tuned as we keep exploring, offering tools, recent information and knowledge of nutrients, their function, how to get products applied.

Going to Go Into The Weeds with Potassium Made Available by Bacteria and fungi

In preparation for this tidbit of news I went deep into the weeds of scientific articles, journals and musings folks.  I came out of it a changed soil scientist.  What?  I had read and been informed incorrectly in the past about the small number of microbes involved with potassium (K) releasing bacteria.  It was known [to me] that only a handful (<6) bacteria and fungal microbes worked on the K from added K nutrients be they inorganic or organic.  Now my head is opened and knowing that more microbes work on potassim latticed feldspars in many areas where K values in soil tests can be high(>250 ppm), it sure does not mean the K is readily available to a plant root system.  In fact many crops we grow struggle to get K – why? Might it be our soils lack the right families and species of bacteria that make K available in an organic soluble form for the root to absorb I asked myself?  Uhhh, duh!

The lifestream in the root rhizosphere again comes into the light so to speak.  Similar to the flora in our gut and in the gut of lactating four legged critters, incredibly vital to digestion and absorption of key nutrients for all of us to sustain life, bacteria are the front-line soldiers.  So how do they make K available?

The group of P, K & Fe solubilizing bacteria and their activities

An overview of the mechanism used by bacteria and fungi to mobilize nutrients (P, K and Fe) in the soil.  See graphic to the right.  Courtesy: M.I. Rashid et. al, 2016, Microbiological Research, Elsevier Publ.

Legend of the graphic to the right of fungi and bacteria aid in the rhizosphere to make nutrients available.

 Indicates processes carried out by microbial inocula(materials/sources  growers add to the soils) to enhance nutrient
bioavailability.
 Specifies primary intermediary steps.
 Specifies secondary intermediary steps.
 Microbial inoculum.  [You noticed too I suspect that these inoculum are right in the first steps of these processes]

Here is a quote from the authors of one of the research papers that made total sense to me as I consider the complexity of microbial action in soils: “Bacteria release various types of organic acids to solubilize K in the soil through various processes such as acidolysis, chelation, complexolysis and exchange reactions. Rashid et.al.”  Those acids are citrate, malate, oxalic, tartaric, succinic, α-ketogluconic acid and oxalates.  Now the complexity grows exponentially and I am not going to go into that because the weeds entangle your feet and mine way too quickly.  As the microbes live, multiply and die they are making K as a nutrient available for the root hairs and epidermis to absorb, move into the cytoplasm and feed the plant for photosynthesis to keep going.  I know I am throwing out a good deal of organic chemistry terms in this, but these acids break free chemical bonds holding tight the K, P, Fe ions on the clay particles and organo-complexes to become available to the root.

Deeper into the weeds:  An associated group of bacteria first have to work on the mineral fraction, the rock or salt types of potassium. only few microbial strains have been isolated that have an ability to oxidize in the first step Fe2+ from primary phyllosilicates mineral in order that they release iron and K from these minerals.  Bacteria species that split iron and potassium apart (Neutrophillic lithotrophs) utilize structural Fe2+ in biotite (the black felspar we see in granite) as an electron donor for their metabolism in order to produce energy and oxidize biotite.  Who are those guys?  The microbes which oxidized biotite (Fe2+-bearing mica) include Bradyrhizobium japonicum, Cupriavidus necator, Ralstonia solanacearum, Dechloromonas agitate, and Nocardioides sp.  During the process of acidolysis, these rhizospheric microbes can chelate Aluminum and Silicon cations associated with K minerals and by doing so they also enhance the exchangeable K in soil solution.  In a series of steps one group of bacteria work on the clay silicates, then another set who need to be there make the potassium available to the root for absorption.  Some other scientific papers identified a number of species:  Bacillus pseudomycoides, B.mucilaginosus, B. edaphicus, B. circulans, Acidothiobacillus feroxidans, Aspergillus tenens and Paenibacillus spp that were right in the soil matrix, thick as thieves on the organic components from old roots, manures, and  dead/inert cellulosic materials.  An important issue microbiologists have discovered that not all of the species are up and living in the soil complex together to make K available or P or N or S or Fe.  I connected some dots in my head then, oh my no wonder we find in soils that crops need K — not all the players are on the roster.  Wow!

You are reeling maybe some from all the chemistry, it is important to note ladies and gents that the microbiological world is so intricate and intertwined to make the soils medium an environment for the root/crop prosper, take up water and hopefully yield grain or fruit.  So what in the dickens does this happen to do with Strip-Tillage on this website?  When we place mineral fertilizers in the root zone with a tool like the 1tRIPr what happens besides us placing it in the root pathway and just expecting all the work out.  Oh the itty-bitty critters that live in the soil (it is said that billions can be alive in 1 teaspoon) have such a gigantic role in making N,P,K,S,Fe,Zn and so on available.  Every year more great research is discovering or uncovering secrets of the soil world.  We are seeing that innoculating or invigorating soils with bacteria and fungi (which I did not talk much about in this blog article) has great promise to support the soil, supplement the line-up of players who belong in making the soil medium have a full roster (I am thinking of a baseball team analogy).  Just placing the nutrients starts the game like throwing the first pitch.  From there on it is the players swatting at the ball, hitting and catching or running it down in a certain amount of time before the harvest machine rolls in.  For all of you, I played baseball, catcher in my high school years.

This kind of reading tells more of the story folks.  I wrote in a previous article about potassium and its importance within the plants growth cycles, this offers you how the root obtains it.  I am excited to offer this.  The world of soil science is still after 50 years firing me up because of the incredible “digging deeper” gives me and hopefully you better understanding.  Are you ready for more?  How about Sulfur in the coming weeks?

References I read to get this to YOU:

Bacteria and fungi can contribute to nutrients bioavailability and aggregate formation in degraded soils; 2016, M. I. RashidL. H. MujawaraT. S.Talal AlmeelbiI. M.I. IsmailM. Oves; Microbial Research, Vol. 183, pp.26-41

Using Phyllosilicate-Fe(II)-Oxidizing Soil Bacteria to Improve Fe and K Plant Nutrition;  Evgenya Shelobolina,  Eric Roden, Middleton, Jason Benzine, Mai Yia Xiong,  United States
(12) Patent Application Publication; 9/2014

Paving the Way From the Lab to the Field: Using Synthetic Microbial Consortia to Produce High-Quality Crops; Z Kong, M Hart, H Liu – Frontiers in plant science, 2018

Phosphate and potassium solubilizing bacteria effect on mineral uptake, soil availability and growth of eggplant, 2005; Han and Lee, 2005, H. Han, K. Lee, Res. J. Agric. Biol. Sci., 1 (2005), pp. 176-180

Beneficial plant-bacterial interactions; BR Glick – 2015 – Springer, Book

Physiology of Crop Production; 2006, N.K. Fageria, V.C. Baligar and R.B. Clark, Haworth Press, Binghamton, NY; Chapter 8

Research on potassium in agriculture: Needs and prospects; Römheld, V.Kirkby, E.A.,  2010; Plant and Soil, Volume 335, Issue 1,  pp. 155-180