Super C Disc Harrow and soil compaction

I've been researching "farming". Seems their is an opinion out there that roto tillers and discs compact the soil. I've never heard that or ever had a problem with it that I was aware of. Bear in mind I'm currently gardening about 1/2 acre and it's been 30 years since I farmed rowcrops. Even back in the day when I operated equipment for Dad and the neihbors I was taught what to do but not why.

I currently mold board plow, disc, then drag with a spike tooth harrow and plant. I am reconditioning a 8' fast hitch spring tooth harrow and may use that before I disc.

What's the science behind the opinion that disc and rotary tillers compact the soil?

when ever a metal point be it a disc blade or a plow share pushs in the ground and raises the soil around it the point is pushed down by the weight of the soil on top and makes a compacted layer. i use a plow and disc alot. just don't do it when the soil is too wet. some soils are worse than others, sandy not so bad, clay ground is most likely to be unforgiving.

In my experience dealing with heavy clay soil, if you disk the ground too wet it does a fine job of compacting the soil. Likewise, the tiller will work the ground into hard lumps when used in the same conditions. Used with the proper soil conditions, though, I do not believe that either tool compacts the ground worse than any other tillage implement. The main point is that they must be used under the correct conditions to avoid problems.

I'm sure someone will say that disks are inherantly bad because they are used to compact the soil when building roads but from what I've seen the disk loosens and breaks up the soil so the scrapers can pick it up easier. I always figured that the sheepsfoot rollers were there to do the compacting.

When they talk compaction, they are not talking about the exposed layer on the surface. They are talking about the layer BELOW that.

Even moldboard plows cause compaction. The plow bottom has to push down on the ground to peel up the top layer and turn over. That causes compaction.

(quoted from post at 10:38:18 02/28/12) I've been researching "farming". Seems their is an opinion out there that roto tillers and discs compact the soil. I've never heard that or ever had a problem with it that I was aware of. Bear in mind I'm currently gardening about 1/2 acre and it's been 30 years since I farmed rowcrops. Even back in the day when I operated equipment for Dad and the neihbors I was taught what to do but not why.

I currently mold board plow, disc, then drag with a spike tooth harrow and plant. I am reconditioning a 8' fast hitch spring tooth harrow and may use that before I disc.

What's the science behind the opinion that disc and rotary tillers compact the soil?

Click to expand...

It isn't so much that a plow, disc, roto-tiller, etc. will compact the soil as it is the number of trips across the field, and with todays LARGE machinery, every trip across the field adds significantly to the compaction of the soil, so in todays farming world, the fewer trips you make across the field, the better it will be for the condition of the soil.

Back up about 50 years or so when the biggest tractor in the field was a Farmall M, soil compaction was not an issue. Your Super C just isn't going to be a problem, and productive gardening DOES require quite a bit of soil preparation.

Naw,

Don't even worry about it with a garden tractor.

Allan

There are at least three parts to the answer. 1. The soil below the depth of the plow is slightly compacted on every trip over the field. Plowing loosens the soil above the "Plow Layer" but the soil below that layer can be compacted to the point that water has difficulty passing trough leading to wet spots in flat areas. This is especially true in areas with low spots that tend to fill as a result of leveling and plowing. Others have mentioned this possibility. 2. The soil disked or pulverized has no "Structure" due to plowing and the fill zone becomes rather cemented and impervious to water transport. Disk and tillers have a reputation for being excessively good destroyers of "Structure" due to flailing and mixing. (Structure is defined as the tendency of clay and silty soils to form larger particle clumps like earth worm pills that allows voids and channels to form for water transport. Sandy soils have a natural "Structure". Earth worms, roots, freeze/thaw cycles, and wet/dry-shrink/swell cracks create structure.) Disk and tillers break down that structure by destroying the particle clumps. Structure will reform over time but it takes time and we are talking decades left undisturbed. Sub-soilers if used in rather dry conditions can break up the plow layer allowing the rainwater to pass through. 3. Cultivated areas that were disked or tilled and then placed in grass or pasture may need periodic sub-soiler or chisel plow attention to reduce compaction and impervious conditions. The earlier disking and tilling tended to destroy structure in the upper zones and additional plowing is not always a part of grass or pasture maintenance. Large amounts of organic manure will improve soil structure by increasing earth worm activity and shrink/swell tendencies but reapplication is needed especially in warmer areas.

Thanks Guys, that works for me. The only thing I haven't done is run a subsoiler.
I never felt the need in my garden as it's a light clay and sand mix.
Hard as a rock when dry and slick and sticky when wet.
I have considered running a subsoiler in the pasture but haven't pursued it yet.

according to john deeres books,the PURPOSE of a disc harrow is to close air spaces after plowing,and to provide a loose but COMPACT seedbed with a good dust mulch.In other words it is designed specifically to pack the ground but leave it loose on top to stop moisture loss to the air from subsoil.What happens is this basicaly,moisture your plants need come to a large extent from subsoil moisture that has soaked into the ground.When you make your seedbed have good contact with the subsoil this moisture can travel up to where it can be used by plants roots, but by leaveing it loose on top(the dust mulch)it stops there for the most part simply because the dirt particles are so far apart water cannot wick away.Cultivating your crops when the soil gets compacted or crusted over after a rain does the same thing.Its a very effective moisture saver.Now ,anything ,any implement you till the soil with compacts it to a certain extent under where plow shares,disc blades,even cultivator shovels and rototiller tines run to a lesser or greater extent.A disc in all reality is made to do that to a greater extent than most,thats exactly what it was developed to do.That being said, some soils never will make a plow sole or hardpan,others are really bad to do it.Most will to certain extent but it could take years of farming to make it.This is why chisel plowing or subsoiling has caught on so much in recent years.Since both have a very narrow tooth they compact the soil far less than say a moldboard plow or disc that has its full weight accross the whole width of the implement,and every bit of soil is subjected to this. When you do get this hard pan two bad things happen,first the ground itself gets so hard and tight that subsoil moisture cannot rise through it.(think of it as burying a glazed clay pot in the ground).Another thing is roots cannot penetrate it so plants suffer either from really dry soil in a drought or a hot summer,or they simply drown from too much rainfall because water cannot get through to subsoil to be stored.Subsoiling or to a lesser depth chisel plowing, breaks up this compaction by lifting the ground from underneath. The small flat blade on a subsoiler for instance pushes up on the soil instead of simply turning it over and fracturing it like a regular plow will.This all sounds like thats the only thing to use but theres another fly in the ointment.First,subsoiling works best when done in the driest part of the year.If its done too wet subsoiler simply cuts a groove that seals back up with mud and you gain nothing from it because water still cannot run down grooves,this IN FACT can dry out your feild even more. Many folks run a subsoiler with mole ball attatched,the pupose of this is to leave a opening TO dry out soil.Sort of like tiling a feild. Bottom line, is you need to figure out what you need for your farm ,your crop,and your style of farming for yourself.We could recommend something we do but that could cost you quite honestly your whole crop and your farm. The place to start is NOT with a plow,subsoiler,disc, whatever.THE place to begin is with a plain old spade. Take a day, go to as many places as you can in a day and simply start digging holes.IF you can dig down 18-24 " easily you have no hardpan and subsoiling and things probably wont show you much gain.If however you can stick your spade in the ground only 6-7 " and hit a area of dry hard soil you probably would benifit greatly by subsoiling or deep chisel plowing.Do this all accross your feilds. The more times the better , make you a rough map and keep notes. You may find you need to take one end of your feild and treat its as a totally seperate farm,or you may find you have a strip right accross your best field that would really be improved by subsoiling.Heres the thing now days, subsoiling,ripping,deep plowing whatever you prefer to call it takes a lot of hp,and its a notorious consumer of fuel.If you find you can get by with just subsoiling one part of feild,or something you probably could increase your yeild and bottom line very much,while doing only whats needed and burning a lot of high priced fuel.The real answer is YOU need to decide whats the best implement to use on YOUR feild.Your neighbor cant do it,we cant, no one else can except the man on that ground.Folks on these forums almost always think that a disc harrow is the solution to any problem ,and it IS a very good tool.But take this to the bank,IF you get good results with a spike harrow THATS your tool because it compacts the soil less,IF a springtooth works for you THATS your best bet simply because it compacts the soil less,IF in fact you need the disc then thats your best bet! I farmed most of my life starting with horses, i personally never owned ANY disc,until just maybe 10 years ago.I bought it then because one farm showed the need of it.Let the soil be your guide ,err on the side of less soil compaction...MY opinion of course ( disclaimer before the argument starts)LOL

THANK YOU ! That was a whole semester of soil science crammed into a few well written paragraphs. I learned a lot.

Years ago farmers had a thing called "crop rotation" which helped soil structure, plus they added a lot of humus to the soil in the form of manure, straw, stalks, etc. Now it's the same crop repeated year after year and chemicals added that destroy good bacteria, worms, etc., along with the bad stuff, and chemical fertilizers instead of "natural fertilizers". Yes, this has led to increased yields in the short term, but IMO has destryed the soil long term. When we moved to a small 100 acre farm in Feb. '56, the first few years we got 65 to 75 bu/acre of corn. By the time Dad had been there 10 years with a lotof livestock on the farm, he had it up to 175 bu/acre. Some was no doubt due to improved plants, but most was due to his farming practices. He alsoo had it figuredout that planting more seeds did not mean more corn or beans either... there was a limit to how much you could plant.