Jodi DeJong-Hughes demonstrates the effect of deep tillage on the soil profile and discusses maintaining soil structure, the types and causes of compaction, and benefits of controlled traffic.
Thank you so much! For the lecturer for the excellent presentation and for the clever mind who decided to capture and spread this precious information! ;-) More and more I get confirmation. That on my small "no till" farm, the old tiny tractor 🚜 I've chosen was the perfect option! :-) Save on cost (acquisition and maintenance), save diesel, save hours of work. save the soil, etc. On the other hand even for such a small tractor, I'm still trying to figure out the best paths/roads. Precisely to avoid soil compaction and also avoid criss cross the 3 different levels of the property with tire tracks...
I'm from N.S. W. Australia. Wow this is the best lecture on this that on this subject that l have heard. We were in self mulching black basltic soils through to sand. We couldn't work out why even sunflowers could get vertical roots because at four inches every root went side ways would stop growing down and only go a short distance even wheat and sorghum would do this. And it would short yellow and spindley on another far it was far worse than this even clovers and Lucerne would only be stunted and yellow and stripey but after deep ripping in a drought(!done to controll severe nut grass infestation twice with Secord working being a 45deg cross rip for the next ten years there was none of these problems or desease issues that had been plaguing us. J had the tractor tyres running on radials set on 16lbs psi there was slippage and so on.
Just watched "Twenty Years of Vertical Tillage" if you want to understand why you and how to till your soil and why plants do what they do and how compact soil stresses them and makes them turn until they find a fracture and hurt bushels/'acre. This video and That video are well worth watching and watching until you understand everything they are saying. The first video is from the guy who thought of vertical tilling. How many guys dig 14 feet down into the soil to follow root growth? Fascinating knowledge as a result.
Not a farmer myself, I'm a dedicated gardener, but if I was growing corn or other crops she has demonstrated excellent points. I turn my soil by hand between every year we plant. I understand air content, moisture retention as well as drainage, along with nutrients needed for certain plants such as tomatoes & peppers to prevent end rot. It's been a learning curve and you only get 1 time a year to make any changes. Our garden is very high yeild and low on desease, except for a root worm problem I thought I had solved using damascus soil, but it turned out to be a failure as I had to pull all our raddishes early after seeing brown leaves/signs of plant distress. Root worms were of course the cause of that distress, and still figuring out a way to kill/get rid of them without using any chemicals. My take away from this is the compaction aspect of it. I have tri-mix soil and obviously don't run heavy equiptment over my garden, that being said, I see the importance of trying to maintain a very none compacted surface. I'll have to be mixing in some pete moss at the end of this grow year as my soil is starting to get compacted.
Which is why I'm digging in 20% biochar deep at the most compacted layer where I grow corn and elsewhere, especially for tomatoes. Since biochar contains air and homes for the micro life it permanently solves all soil issues.
Great videos! Thank you! I have a few closely tied questions: Why does the compaction depth not change with ground pressure? I understand from watching your videos that with lower ground pressure compaction intensity will decrease at all depths but the compaction will still go equally deep into the soil. Is that correct? If the above is true, what determines the compaction layer depth that a tractor leaves behind? How is it related to intensity and depth? I look forward to your reply. Thank you for your time.
The compaction intensity varies due to your soils ability to disperse weight. If you push down on the soil with a 1 inch rod, the rod itself will leave roughly a 1 inch hole, but the compaction happens in a cone shape below your hole. Think of how grain piles up in a bin, in a conical shape because the weight is distributed evenly in a cone beneath the auger or source. The same thing happens in the soil, the weight is distributed evenly as well. Every grain that has weight applied to it spreads that weight out to the grains that are holding it up. The more weight the more compaction, but the level of compaction stays fairly stable due to this dispertion of weight.
You are asking great questions. Soil compaction is not an exact science. There are too many factors that contribute to soil compaction to accurately predict depth of compaction. These include: soil texture, soil moisture, organic matter content, restrictive layers, soil structure, tire/track psi, axle load ... However, when it comes to factors we can control, we look to tire psi and axle load. The heavier the load the deeper the compaction. The higher the psi the more intense the compaction. There is research out of Ohio State University that shows psi also affects the depth (as well as the intensity). Research has also shown compaction down to a depth of four feet, but more commonly down to 2-3'.
2 things. 1. At what point is ineffective? For example you said it’s been shown that compaction can be found as far as 2-3 feet. My question is at those depths how intense is the compaction, does it actually affect the crop? 2. Thanks for not calling that school ‘THE’ Ohio State University
You have made many good points. But in some instances not plowing can cost money. We run a disc ripper every other year and other tillage practices on no till. But if we have to go corn on corn plowing the cornstalks will gain 15 bushels and we have friends that have found the same response.
Load bearing capacity of air depends on atmosperic pressure, but the range we have in the atmosphere naturally is very low even at the highest pressure level. Think of a boat... it floats on water, but not in the air.
No Till is fine for a few years as far as this teaching goes but after a few years of not opening your soils deeper soils will compact over time and not allow the moisture to penetrate deeply. What are the average of years a farmer can go with NoTill before they should cultivate deeply and open up the soil again and Rejuvenate and bring the deeper soils up and turn your soils over?
Hi Robert. Where do you farm? MN has very forgiving soils because we have fairly young smectitic soils and our soil has 3-6% organic matter. We don't want to till up the tan soil that sits under our beautiful black topsoil. It dilutes the OM, pH, and nutrients, ... Building soil aggregates will rejuvenate the soil, improve water infiltration and store more water for the roots.
One of the comments struck home.." No one knew how to set the plow" Is it so bad that plowed residue is slower to break down? To me that seems like a good thing as it is a sign that the residue is not being converted rapidly into carbon dioxide and global warming. Much of the criticism of the moldboard comes as a result of not knowing how to use it, how to set it, how to maintain it, when to use the plow, when not to use it. Correct soil management using a moldboard plow is much less damaging than disc rippers and chisel plows. The ripper style tools totally annihilate soil structure completely disintegrating the fungal environment whereas a properly set, properly used moldboard will cut and turn a slice of soil and does not completely annihilate the biological environment. On the subject of plow pan there has to be a distinction made between a change in soil density and a plow pan. A change in density is created by a plow but a plow pan is created by over inflated tires in the furrow bottom, plowing at the same depth year after year, a poorly adjusted plow, worn out ground engaging parts. Soil doesn't mind the appropriate use of a moldboard plow in the rotation - how do we know this? Yields and profits increase. The moldboard plow is not an environmental and soil health problem. The misuse of the plow is the real culprit. best regards Jim
Where I am we have issue with keeping organic matter from breaking down too much as the ground is saturated and doesn't quite freeze in winter. Spring plow with a disk is too late to break down sod and weeds and fall plow breaks down too much and substantial nutrients leach. Early spring moldboard is just right. The main issue here is that the organic material is then buried so deep that it has no benefit to seedlings.
Sooner or later it will change. I'm in SC, I live in a very low place, top few inches beautiful black soil then dark clay. Few years ago I embarked on a adventure, I drilled a well by hand with a auger. I started under a 15 off the ground limb to help hold the pipe when I pulled bit up. I used two large pipe wrenches to turn 3/4 sections of galvanized pipe. Started with post hole diggers to about 3.5 feet. At about 10 feet I hit red clay,took many turns of pipe to get mabe 8" in any kind of clay, then all of a sudden pipe drops several inches and I pull up the whitest beach sand you ever seen, that layer might have been 8" thick, then I hit some kind of blue, gray marl clay mabe 3feet thick, then all of a sudden pipe drops again and I was back in sand. The Atlantic Ocean was over my property in the past, I'm around 90 miles from myrtle Beach.oh,in a very bad drought I hit water at about 12 feet. Property is only around 200 feet above sea level.
