Agronomics101

How is Soil Water Important to Developing Plants and Fertility?

Couple three weeks ago I laid out some items that may provide clarification to a developing root system, first I shared about the fertility placement and then wrote to you how soil porosity (abundance, size and continuity) is so important.  Soils that are massive or compacted will inhibit root development and depth of penetration for so may crops, perennials can adapt and push through over the years.  For an annual plant such as corn, soybeans, dry edible beans, canola – oh we have problems.

So let us consider the water content of soils, where the water is in a soil profile, if there may be a dry sandwich layer (more moisture above a dry zone and wetter below), how much suction power (or not) does a plant exert to draw moisture into the roots, that ‘zone’ around the physical root diameter for water uptake, how far can a root dehydrate or drink water from the root itself, how much that is and briefly what mycorrhizae hyphae does in aiding water uptake.  All of the above are factors along with climatic conditions; humidity of the atmosphere, heat of the day, wind and then crop stage.

Fig. 1:  On the left is very young plant at V4, the right is a plant at VT

 As a plant ages the amount of biomass that is alive has a certain demand for water; for instance, a V4 corn plant is only 13 grams but a fully mature plant with a developing ear may be 2450 grams – 190X more grams and surely a bigger demand to keep hydrated and functioning.
Images to your left represent what we might be looking at….

Facts of water holding capacity:

When the soil matrix is near field capacity for a medium textured soil (silt loam or loam) it can hold nearly 0.34-0.40 inch/cubic inch – what is available tho is 0.21 to 0.22 inch per cubic inch.  So in a root zone of the V4 plant the root zone is fairly small, potentially in 144 cubic inches of root zone it could have 16 oz of water available to the root system.  When a plant has reached maximum height, maximum root volume in the soil (VT-R1) we are seeing 5000 to 6500 cu. inches of soil volume that can hold water and make it available to the roots.  If soil profile is at field capacity when plant is mature we are looking at 21.6 to 28.2 gallons of water available.  Compare that to 1 cubic yard then we would have a field capacity 202 gallons available in a silt loam soil profile.  Great potential, however those numbers at that stage of growth in a corn field are extremely rare.

Facts of Dryness:

Consider how a soil will be refilled by rain events or irrigation in a medium textured soil (bear with me), the profile has to over fill the upper horizons first to help push water downward through cracks, crevices and pores as well as gravity pulling it.  A soil that may be very dry, down to near the hygroscopic range, the soil fills somewhat slow then seems to catch up and water moves into the soil profile.  There are times when the soil is so dry a condition called “hydrophobicity” sets up and water will be shed and runoff (not infiltrate).  This happens during long drought spells and when a fire has swept across the surface at temperatures up above 500 degrees F.  Waxes, lipids, fats and resins in the soil organic matter are the usual culprits that cause such an effect.  A 25mm or 1 inch rain when the soil surface is real dry will rarely fill the upper portion of the soil profile evenly.  In a strip till environment we find that a 25mm or 1 inch rain may penetrate 30-35cm (12-14 inches) in the strip tilled area but only 10 to 15cm (4-6 inches) between the strips when it is very dry.  Part of the reasoning, we have observed over the last 20 years in strip tilled fields the  residue between the strips may shed water towards the strip zone, and the porosity and shallow roots under the residue absorb water very quickly.  So I am telling you this to say the soil profile will have dry spots, shallow depth in parts and in strips deeper penetration – this gives the plants an advantage in strip till.  The existing pores under the residue where the soil surface has not been disturbed in most cases will have contiguous pores under where last years crop stood and aid in water penetration unless as I said it is super dry like the 2020 late summer into fall and winter.

Fig. 2:  Courtesy Gary Naylor – Intense rain on soils that puddled bad then soils flow and erosion is severe.

Compacted Soils – And Potential Soil Erosion

I have observed and also measured water movement when soils have a compacted layer within the upper 6 inches (15cm).  Ugly effects.  What happens?  Because of what we call an “abrupt discontinuity” at the top of the compacted layer there is a smear zone.  Pores, cracks, crevices, even some of the vertical ped faces can be cut off or truncated, as with a rapid rain events or large doses of irrigation (flood) the soil above the compacted layer has to fill to 130% of field capacity before gravitational water starts to pull water in and down.  What does all that have to do with soil water?  A bunch, when water is not able to penetrate the soil profile and refill pores so a growing plant can survive – we have problems; the results may well be runoff carrying away soil for a period of time unless the rain slows to a infiltration rate below the normal soil textural rate (ie: loam soils have a standard infiltration rate of  0.6 to 1.0 inch/hour, silty clay loam soils standard rate is 0.2 to 0.6inch/hour).  When soils become that saturated and the rain continues to pelt down at a high rate (>1.5-2 inches per hour), the soil above the compaction usually turns into a gel like substance and then flow – water erosion becomes horrendous.  Image to your left is a perfect example – losses may exceed 50 to 160 tons/acre.

The amount of water that we hoped to penetrate and go into the soil and replenish what the plants have absorbed or evaporated will be way short of what could and should have refilled the soil.  Now please do not think that moldboard plowing is the answer.   Strip tillage shanks or coulter units follow the normal vertical structural units of the soil and disturb the soil without inverting, smearing, rolling and smashing soil structural units.  All of those disturbances damage soil structure which can and will alter soils to become massive, reducing porosity and that results in  less water content for root access.

Water is the essence of plant life.  Without water and at the right times plant desiccate, wither and die.  Water obtained and drawn into the plants by the root system move sugars, proteins, carbohydrates and basic nutrients into the xylem and phloem tubes to continue the cycle of photosynthesis.  It is said and studied by plant scientists that 98%+ of the water in and used by plants come from the soil profile.  I can hear several of you say – That is an understatement or in one word, DUH!  My writing such is to note we are farmers of water and the soil profile is the bank account we manage with certain tillage practices.  This discussion is to emphasize with what we promote with Strip Tillage we are helping you with water infiltration, where it gets banked, making a root system as big as necessary to grow a crop whether it is forage, grains, fruits, tubers, bulbs or nuts.

Effective zone around the root and root hairs can obtain water:

Fig. 3:   Diagrams of zone where root of 1mm size pulls water.  The red line indicates the distance water can be sucked into the plant (1cm to 2.5cm) on the left.

Roots have to compete against the tension water is held by organic matter and clay particles in the soil to pull water into the epidermis and then Xylem transports it up to the above ground portions of the plant for cooling, hydration and photosynthesis processes.  The suction can be measured in atmospheres, pounds of force, or dynes.

In the diagram to the left there is a cross section of a root and then a red line around it giving you an idea of how far the root can pull or suck water when the soil pores are full of water, the tension soils hold water at that phase is 1/3rd of an atmosphere.  That is easily obtainable water and the plant exerts little effort.  For ease of reference to remember, that is 1 to 2.3 cm or approximately 1/4 to near 1 inch around the root.  Finer root size can squeeze into smaller pores, the larger roots when growing fast and down deep do not send as many roots radially outward and may grow past drier zones for cooler and more moist environments.

FIG. 4:   Depiction of an Orthman root dig with very fast vertical root development (red circled area) shows where very, very few lateral roots developed

With this drawing [Figure 4] of a root dig we at Orthman completed in 2012 with fast growing conditions of the hot summer, roots show little to no lateral root expression within the 18-32 inch depth. At the time of this root dig it was late August, the plants were mature and had finished pollinating.  We returned near to the same site after harvest, dug new holes and discovered the zone 18-32 inches still had moisture and the rest of the soil profile was bone dry.

My intention is to illustrate that both lateral roots and root hairs can make a significant difference in water uptake.  Then with the later soil-root dig we observed the remaining mosit soils.

 

Lastly, Mycorrhizae hyphae contribute to water uptake:

The ever emerging and broader knowledge of mycorrhiza is fascinating and a study in itself with how and what they contribute to crop production.  I have written about this fungi before and will just briefly identify in this article what they contribute to plants in water uptake.

The hyphae are small filaments microns in size that grow out from the hosts root into the soils in the upper 4 to 12 inch depth of the soil profile.  Aerobic in nature they do not live too much deeper into the soil.  These hyphae can extend outward from the host plant up to 10cm (4in).  As they do they can absorb water and nutrients to feed its host to continue growing more hyphae.  Brassicas – plants of the mustard family do not have a symbiotic relationship with mycorrhiza.  Nearly all other terrestrial plants do.

A very interesting feature of these symbionts that they aid the plant handle droughty conditions.  Even cactii have a solid relationship with mycorrhizal fungi and thrive due to their interaction.  Offering  another quick fact about mycorrhizal hyphae –  Glomalin is a glycoprotein produced abundantly on hyphae and spores of arbuscular mycorrhizal fungi in soil and in roots. Glomalin was discovered in 1996 by Sara F. Wright, a scientist at the USDA Agricultural Research Service.  I had the honor of meeting Dr. Wright when she came to the Great Plains USDA-ARS Experiment Station near Akron, Colorado and she taught a field course about her discovery, identifying the microscopic filaments, the importance of glomalin as a “soil glue” and soil aggregate stability.  Since that date the science of soil fungi has exploded and brought so much more to the science of soils.

FIG. 5:   Computer image of a soybean root (in yellow) and the hyphae near the surface are very fine in size.

As I said water is absolutely essential and provides life or without soil waster most plant life does not exists.  Offering you a small window into the realm of soil science that incorporates physics, biology, chemistry, and specific root relationships that are of recent findings.

Stay tuned as we explore more.

Soil Biopores from Previous Crop – Influences 2021 Crop

Fig 1. Example of compacted root system of canola visualized by X-ray tomography Courtesy Univ. of Adelaide, Australia, 2004  Lateral root expression at 12 to 15cm depth due to compaction. Root volume is then 80% of the root mass is in the upper 20cm (8in).

As I wrote last week that I would update you the reader of the PrecisionTillage blog on more facets of rooting, tillage, nutrient uptake and also water uptake.   As I peel a softball sized onion of how soils are so important to every nuance of crop growth, I find more research I need to read, digest and cover to provide you important clues on how to raise a profitable yield. Over the course of a few days working here at my office I have read some interesting material.

Han, Kautz & Köpke (2015) observed in a study of crops following chicory (a taprooted plant) and a planting of tall fescue which produce quite different root systems. In their research growing barley after the taprooted crop vs fibrous fescue, the roots sampled after the tap rooted chicory resulted in a higher Root Length Density (RLD) of two upper root diameter classes (medium and coarse roots; 0.38 cm cm−3) in comparison to tall fescue (0.23 cm cm−3).  Roots come in four root diameter classes, very fine (<0.1 mm), fine (0.1–0.2 mm), medium (0.2–0.5 mm), and coarse roots (>0.5 mm).  Their data suggest the root architecture of precrops resulted first in different patterns of soil biopores, second in a different morphology of the root system of the subsequent crop and third in amount of soil explored by subsequent crop root systems.  Their work detailed that roots of the fine and medium diameter size increased the RLD overall.

In research efforts we carried out at the Irrigation Research Foundation (2004-2007), we determined that with a Strip Till then plant approach in irrigated corn the medium and fine roots increased 4.4X in number under strip till compared to a chisel/disk/springtooth harrow then plant system. Consequently the water infiltration rates improved from 0.6in/hr to 2.9in/hr and more in the 3 year study.

Modeling with X-ray tomography methods in Germany researchers have determined that soils that are compacted (in the upper 25cm-10inches) rely upon the biopores throughout the soil profile in small grains to take up water, nutrients, exchange gases (O2,NO, CO, CO2, etc) and to penetrate greater depths [M. Landl, A. Schnepf et. al, 2019].  Using some modeling processes the researchers simulations suggest that the influence of biopores on root water uptake differs for different soil densities as well as soil types. Due to the larger increase in rooting depth, vertical biopores had a more beneficial effect on root water uptake in more compact soil. Furthermore, the effect of biopores was more evident in a sandy loam than in silt loam due to the sandy loam’s higher soil hydraulic resistivity when the soil was nearer to hygroscopic water conditions.  Landl and her fellow researchers went on to say, the positive influence of biopores persisted even under the assumption of reduced root water uptake in biopores due to limited root–soil contact within the pores and was larger for dense soil than for loose soil, again this was specific to sandy loam textures over that of silt loam soils. Improvements of 9-24% more.  In Figure 1, the canola plant root (a taprooted crop) followed an old biopore until it hit the compacted zone then turned lateral.

Fig. 2 X-ray tomography images of canola root at 60-112 days growth entering the subsoil.  The yellowish root enters surface tilled soils in B, and encounters more dense (compacted zone)as plant matures from left to right in C, D and E.  Image courtesy Univ. of Adelaide, Australia

 

The images to the left depict a series of the X-ray tomographs from 60 days after emergence to approximately 112 days after and what transpired with root development as it encountered the compacted subsoil.  The red letter “a” points out across B-C-D-E where the roots enter biopores to penetrate the compacted zone.

Comments and Suggested Conclusions:

Both sets of authors I have referenced here have quantified to a degree that roots from subsequent crops are influenced significantly by size of biopores from previous years and tillage.  Our work at the IRF verify that old biopores that are still in tact and continuous into the subsoil influence root development and water uptake.  We determined in the IRF study that strip till played a significant role in larger biopores being developed in corn and accentuating roots to penetrate further into the soil profile.

These kinds of data for me say that a crop rotation of crops that leave larger pores (medium and large as described above) have a role in water management, potential drought survival, more potential for the crop to develop a robust root system and possibly yield improvements.  It is a goal of ours (Orthman) this coming summer with aid from an intern and the Vo-Ag students carryout some root length density observations where we will be 2 years corn on corn compared to last years soybean crop.  Keep tuned in.

 

References I used for this blog:

, & Precrop root system determines root diameter of subsequent crop, Biology and Fertility of Soils volume 52pages 113–118

Landl, M. et.al; 2019, Modeling the impact of biopores on root growth and root water uptake., Vadose Zone Journal, Vol.18, Issue 1, pp.1-20.

A couple-three new facts about the Farmers Nemesis – Compaction

I think everyone who have been reading PrecisionTillage.com have come to getting the idea that we at Orthman Manufacturing have a very reasonable grasp on the big issue surrounding soil compaction that pesters growers using larger and heavier equipment.  Agronomic scientists and practioners from all over the globe, who study, evaluate compacted soils using penetrometers to assess the intensity or severity of dense soils is dealing with how to deal with the issue and how to minimize compactions effects. I know I continue to make strides to keep current and educate myself and the team here at Orthman regarding the limiting effects of soil compaction.  Just in the last week I have come across some little known facts that I want to place in front of you.

Where is it that soil density starts to impede (slow down) root elongation and penetration of the soil profile?  Impedance is observed in the range of 1.2 to 2.0MPa (174 to 290psi) of resistance measured by cone penetrometers.  Most plants we grow can easily create those kinds of force at the root tip when 70-85 days of age after emergence with adequate water resources being available.  A question though comes to the forefront, what about when the corn, soybean, grain sorghum, cotton or peanut plant roots are less than 40 days after emergence?  I say this because once roots encounter resistance in the soil above 2.0MPa, the root length can be decreased between 50 – 60% of normal growth and extension.  Certain species like alfalfa have high energy levels and turgid pressures

Fig. 1:   Heavy traffic prior to planting shows strong evidence of plant emergence that  has been reduced consistently by seeing the traffic pattern 

as well they are larger in diameter in the existing roots which I read in 10 different scientific papers provide the ability to penetrate more dense soils. When soil resistance exceeds 2.7MPa in maize root tip extension comes almost to a halt.  It has been measured in young maize (corn) plants in greenhouse potted plant studies that at the root tip there can be at 35-40 days after emergence from 40 to 140 psi (≤1.0MPa) of force to extend roots  into more dense soils to attain water and nutrients.  When roots cannot press the root tip through dense soils they will deform or become more plastic to change axial directions and seek an existing biopore (old root channel) to continue elongation.  Recent efforts in soil core studies with compacted layers and X-ray computer tomography technology, Nottingham University – U.K. determined that new roots will colonize (their term) old root biopores. Root tips are able to sense the change in oxygen levels from the pore and then grown downward many times co-mingling with other roots.

As we consider those kinds of values I believe we all should be taking a look in our fields before we pull the planters into the field next April for you folks in the Northern Hemisphere to gauge if any compaction is going to cause plant growth issues, water penetration and permeability of water into the deeper zones of your soil profiles.  Then roots will get there too. Soil strength (compaction) is a leading major cause of inadequate rooting. It affects nearly all soil bio-physico-chemical properties such as soil porosity, water conductivity, microbial populations can be reduced (especially aerobic bacteria), plant resistance to disease or insects, and nutrient availability.  Millions of acres (hectares) of agricultural lands are affected globally.

When root systems of corn for instance are retarded or held up to only explore and grow in the upper 20 – 24 inches of a soil profile, the water supply and nutrient supplies will be exhausted before the growing season is over.  Thusly limiting total biomass that needs to be developed and yields of grain or forage will suffer.

In your tillage management thinking, prior to planting, if you are seeing evidence of compacted soils with less than desired plant stands, water runoff or ponding, ruts from harvest or spray rigs, purple looking corn early last season, stunting, floppy corn early in season, use of tandem disks when it was wet – look into the Conservation Tillage method of Strip Till.  Compaction is almost every time man derived.  But it does not mean a moldboard plow or a massive ripper tool is the answer to fix what happened.  Check out us here at Orthman or a dealership that sells Orthman strip till implements, we would like to help, suggest and point your eyes in a direction of a very top notch Strip Tillage Systems approach.

From all of that in a quick summary, what is it that is new that we have not talked about before?

  1. Impedance(in soils) when observed in the range of 1.2 to 2.0MPa (174 to 290psi) roots are dramatically slowed

  2. Once roots encounter resistance in the soil above 2.0MPa, the root length can be decreased between 50 – 60% of normal growth and extension

  3. Recent efforts with compacted layers and X-ray computer tomography technology as roots attempt to penetrate compaction they can sense oxygen levels improve and change their tip growth direction to extend into a biopore, worm tunnel or old root cavity

I will keep you up-to-date with new items on this website as I read, come across or learn new material. Do not hesitate to contact any of us when you see on the Home page of this website via the Contact tab.

Northeast Community College – Norfolk, NE Looking to Cooperate with Orthman Mfg and AKRS John Deere

November 25th a small group all spaced out and wearing masks as though we were planning the next stagecoach robbery of the 1880’s – we met to discuss and evaluate for all parties (AKRS John Deere, Orthman Mfg and NECC) a new venture in how strip till is a viable option for advanced precision placement of dry fertilizer products on a section of the NECC farm.  Numerous other partners are working with the college to study new technology from Population of soybeans SmartFirmer add-ons to emergence studies of corn and soybeans to the Soil Health Project.  Seed companies, Fertilizer distributors, implement representatives, SARE, USDA-NRCS all have been involved in the 2020 Applied Field efforts of research to educate and inform students and members of the larger community of NE Nebraska. Looks like many will return for 2021.

Newest addition for the Agricultural Center at NECC-Norfolk, NE

We at Orthman and AKRS-John Deere are excited to be part of what can happen for the entire Agriculture community and students that attend NECC.

The image to the left is still under construction and partially in use as of November 2020.

It is Orthman and AKRS-John Deere’s hope to work with the farm manager at NECC to study some issues of whether compaction with large frame rubber tired 8R series tractors and 8RX track tractors is better, worse or in-between.  Along with that we will be strip tilling with the tried and true Orthman 1tRIPr and placing dry fertilizer precisely under the soil surface to look at efficiency, proper feeding of the corn root system, and potential yield.  This will be compared to a more standard method of dry broadcast.  Our hope is to communicate with the Soil Health Partnership folks as well.

Keep coming back to this website for updates as we move into 2021 with the eager team at NECC.

2020 Orthman Post Harvest Exploration of Roots Enhanced by the Strip Till System

Today I am offering you a look at how well the roots of the hybrid we strip tilled in fertility two-three weeks prior to planting back in early April of this year [2020].  This information and root map is on the Orthman coordinated approach at the McNaught farm north and east of Polk, Nebraska in some beautiful loess derived soils.

I want to describe the root system in regards to what features are enhanced with our (Orthman Mfg) approach to foundational work in the upper portions of the soil profile.  Alleviating compaction, developing a seedbed and placing an initial balanced, nutritional dinner plate of goodies in the soil for the young plant is all part and parcel of this approach.  We want growers to set up their crop for reaching the intended farmers goals.  Yes there are those that shoot for the 300 bushel club, many details have to work just so – one being climatic factors of rain, plenty of sunlight (2020 was good for that), no big winds or hail.  There is yes the concept of hybrid selection.  Not all hybrids of corn will magically excel with Strip-Till.  However knowing more and more about how corn responds in the environment we create with the Strip Till approach can provide some great yields that make the grower return on his investment and – profit.

To your left is the root profile of a Pioneer hybrid 1185Q we planted on April 29th at 30,000 seeds per acre with a final population of 29,640.  The depth of the soil profile is numbered on the right side of the Y axis (vertical). Then on the left side of that vertical axis is the quadrant depths of dividing up the root profile by volume in quartiles. In volume the root system was 65% 0-14 inches, 20% 14-27 inches, 10% 27-48 inches and 5% to the depth of 70 inches.  All of this was excavated by us with a small TrackHoe provided by our good cooperating John Deere folks, AKRS in Osceola, NE.  This view of the the profile details where the first 65% of the roots take up volume, absorb water and nutrients and then the next 20% and so on.  The dominant 95% of the root profile extended to 48 inches – that is a fantastic root system.  We calculated the root-soil volume for this hybrid to be 6,090 cubic inches of soil explored by roots.  All of this better evaluates from our expertise in Soils and Agronomy here at Orthman Mfg what changes a Strip Till system does to growing big corn and better yields.  I have been engaged in observing soil-root pits post-harvest usually every year for over 24 years with USDA-NRCS and now 14 years for Orthman, some 1745 root pits.   For those of you wanting to know, this hybrid tipped the scales at 60.5lbs/bushel and 256.5 bu/acre (and that was with some percentage of wind damage that caused GreenSnap in July).

An important feature from this root dig folks, is that we see a better profile of the underground root system with Strip Tillage and proper below ground placement of fertility products.  We also counted the number of roots in the root crown to be 50 out of the potential of 60-62 roots per plant.  That helps in the overall yield potential at  reaching 83% of the maximum root number growth per plant.  Since 98% of the nutrients are brought into the plant via the root system taking it from the soil solution and the great relationship of bacteria in the soil living on the root as well as mycorrhizal fungi symbiotically feeding its host – the corn roots in the upper 10-12 inches. This all makes what you plant seeds for come to the 100 fold and more multiplication factor of one seed become reality.  Whether you consider Direct Seeding or Multiple pass Tillage or Strip Till then plant as what you see is best for you – we desire all to see what Orthman Manufacturing, Inc does to educate, inform and cooperate in on-farm studies with others in the Ag Industry to improve the farmers lot in life.  Our cooperators; AKRS John Deere, SureFire Ag,  Nutrien, North Forty Seed are all associated with us to offer a scientific approach to producers and see the benefits by doing it joining hands and efforts.

My questions to any of you as you read down this far and gazed at the root profile; do you know your rooting profile by hybrids you plant in your soils?  Does it seem to provide you in this information that top performance comes from better management practices in your tillage, your fertility program, your management of water either rainfall or irrigation? Did you place nutrients not just Nitrogen below the growing plant wisely?  If that has not what you’re experiencing presently wherever you till soils, we sure would like to engage with you, offer our expertise, our skills from our Territory Sales Managers as well as my own, and our strong built tillage tools now since 1965 to move the economic yield needle for you.

You can reach us at our email addresses located on the Home Page of this site under the Contact Us tab. As the leader nationally and internationally in Strip Tillage we really want to provide up-to-date resources for all to go the next steps in being the best manager of your soils and water resources that get solid yields every year.  Our partners that I mentioned in the 4th paragraph are of that same mindset folks.  We want to Get To Work For You. 

2020 Harvest Results from the Orthman-McNaught Farm – UPDATE and Thanks

CORN HARVEST 2020

The past few days I have been pouring over the corn yield data we obtained with the Deere S770 combine during the week of October 5-8.  I am waiting for approval from all our partners before I release this data and observations/conclusions.  Most likely end of next week folks. What I can tell you in this short update that across the farm the two Pioneer varieties we used did quite well with the management program of tillage-planting-irrigation-fertility-fungicide-herbicide and doing well to be timely according to the plant physiological stages.  Yes that was a mouthful, albeit so important for you to realize timing with corn is what allows any of us to tip the scale to have real solid yields that make money.  The entire farm average was 231.5 bushels per acre with the corn moisture running between 16 and 18.2% and 60-61 lb per bushel.

2020 Harvest

I must provide you with a caveat, the field was hurt by a down-blasting wind back in July that caused 30-35% ‘Greensnap’ damage just one node above the ear placement on the stalk.  Local observers clocked the wind speed on that evening of 60-65+mph. It was not that severe across the entire farm but two fairly large spots in a transect/swath from northeast to southwest was more than enough.  Yes it was disappointing and on the day after – deflating to say the least.  What we did see (a peek into what is coming) the yields where the wind damage was less than (4%) we were 269 bu/acre and the low was 203bu/acre.

Acknowledgements:

We want to thank AKRS John Deere organization for being good with getting us the equipment of the corn head and S770 right on time and being there to aid and support from the April strip tilling and fertilizing to hauling it away.

We are very thankful to the team with Nutrien and all their participation as well as lending a hand nearly every week throughout the season – tissue sampling, soil sampling, watching over the crop for bug issues or disease, super job men!

North Forty Seed Co. was right with us all the way and Nick Hatfield was always helpful giving us information about the two hybrids we selected along with what was in the Variety strip trial that faced Road F.  I will say this, growers keep your Seedsman’s phone number handy when you work with his/her hybrids – they are a great resource as they work with you on your management plan.  That is not to rip on him/her but to gain their knowledge and information is the kind of relationship I am speaking of. Nick is just that kind of professional.

All of us thank the young high schoolers from High Plains FFA and Cross County FFA for pitching in when we asked  them to , to collect pages and pages of growth data and gaining “hands-on” agronomics in the first three months of the growing season.  Then some were able to come out for harvest.  Nearly everyone of the Vo-Ag students from both schools attended the August 26th field day and exhibition at the McNaught Farm.  Five of these sharp young folks  gave a knowledgeable talk in front of the 100+ folks on a large screen TV that Orthman Mfg. team brought to serve lunch and use the audio-video equipment to provide a great day for all.  I as the scientist for Orthman am incredibly proud of them.

I do sincerely thank our good friends and supporters at SureFire Ag who provided us the top-notch equipment to deliver the fertilizer products from April’s strip tilling pass to planting to cultivating and ditching with more nutrients.  Your equipment worked flawlessly, gave us a confidence that we were putting on the products at the right amounts, in the right location and on time.  When we needed him Mark Griffith he was there and the guys back in Atwood on the help line – Kudos!  When carrying out replicated studies we knew that SureFire Ag was our set of tools to do the job.  The results will show!

A shout of thanks to Randy Harliss there in Polk, Nebraska who sprayed for us.  We really appreciate you and your guys when we needed fuel and materials to spray for weeds and all.

As the science guy who can be blamed for a ton of comments, questions and stupid looks of why in tarnation we gotta do… I thank Pat McNaught for putting up with my quirks, science-guy geekness, wanting it just so, some nagging, a starter trial of 23 acres which was replicated/randomized four times, digging holes, pulling ears (cause of maybe the reduced yields), walking in and out of the field a zillion times.  Your patience and love of the farm is gold with me sir. For Doug Peterson all your being there for a 61 different reasons we asked of you – Thank You.  To Justin, Pat’s and my supervisor; a big Thank you for being an advisor, a soundboard, giving us time and the go-ahead to pursue this research work, stressing we do the field event and the exposure you knew would be good for Orthman. To our owner of the company, John McCoy, we set out to prove several details about Strip Till by the tool that tills in thousands of fields and the 1tRIPr works  around the globe and we did them sir.  When I get the more robust report done that details the season long comings/goings cleared and report by times we looked at crop responses you will see the solid positive results. We thank you for trusting us to expose the Orthman Team as a company “Doing it Right” and a “Hard Act to Follow”.  Many thanks to my cohorts who came for the field event jumping in and doing so much; Tim East, Gary Mohr, Justin Cross, Heath Carlton  — Many Thanks guys!

Do watch now for what will come from the yields soon.

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.