Soil Compaction

Hey all. I've been thinking about this lately, and wondered what wisdom you all might have. I've worked on several small scale organic farms and a few gardens as well while WWOOFing. One farm in particular was very adamant about not stepping on the beds (except when broadforking), yet all were relatively worried about compaction, aside from the one tractor scale organic farm where they didn't care at all (but probably should have, but that's another story...).

I now run a small market farm myself, and think about this sometimes. Personally, I do avoid repeatedly stepping on the beds, and it gets regularly broadforked and rarely tilled (mostly I clear beds with a stirrup hoe); and with all the soil life and organic matter content, I don't feel stepping on it a bit is really all that bad, unless it's really wet of course. I just don't see the soil as being so fragile that it can't handle my weight (I'm on the small side for a dude) for the space of a second as I pass by. I feel like the worms, beetles, and other larger (and smaller, probably) creatures can reopen any spaces I crush down pretty fast. The soil has a good bit of sand in it, by the way, though is on the clay side mainly.

I guess my question is, if you have generally healthy soil, with high organic matter content, good soil biology, and good crumb structure... is it really that big of a deal to step on it a bit? How anal should I be about staying on the paths? Most of my internet searching seems to be discussing pretty damaged or degraded soil, but I wonder if you already have good soil if it's something to be overly concerned about.

I wouldn't worry about it, at least human feet on soil. In regards to people walking on soil, I would call it "firming" not compaction. There may be some element of concern for compaction with heavy farm equipment repeatedly rolling in the same tracks over and over, and maybe more so if the soil is saturated. You're right about the worms and bugs and all the soil denizens moving about gently pushing soil particles aside as they live out their lives, loosening any firming that may have occurred while working or kneeling in the garden. If any kind of compaction has occurred, the winter freeze & thaw cycle will undo that, preparing the soil for spring sowing.

I stopped worrying about that at all except when it's wet and then only because I have heavy clay.  

We teach a variety of "primitive" skills classes. One of the things we talk about is how people walk. It's quite amazing really. Go for a walk thru fields and woods with most people. Watch what they are doing. Most people, especially city folks, walk with their heads down and eyes at a 45* angle. They don't much look up, they don't much look around. They miss a tremendous amount of life all around them as they walk along. I've seen folks walk right past deer and never notice. They miss the fox dens, and bird nests. They simply have little of the situational awareness that comes from looking all around as they move.
--So to your question about walking in gardens. It's the same to me as walking across your yard to your barn or house. If you always step on the same place, that place will be compacted. In your yard, the grass will die in that path. In your garden the "hardened" soil will grow plants less well. So, I tell folks to be aware. Think about where you are walking. If you ask the same blade of grass to bare your weight as you pass, the grass will suffer. If you keep treading on your garden mounds, ...well. Do as little damage as you can as pass along somewhere. Be aware of your actions. Try to play nice and the Earth and all her peoples will be happier for it.

I guess my question is, if you have generally healthy soil, with high organic matter content, good soil biology, and good crumb structure... is it really that big of a deal to step on it a bit? How anal should I be about staying on the paths? Most of my internet searching seems to be discussing pretty damaged or degraded soil, but I wonder if you already have good soil if it's something to be overly concerned about.  

Compaction comes from heavy weight being put on the soil repeatedly so that the structure of the soil literally welds the particles together.
Good soil with the nice structure you describe will not be easy to compact by light foot traffic. You will see foot prints but as you surmise, those will go away over some time.

Places in a garden that will face compaction are pathways where you are constantly going back and forth with your feet and wheeled tools, the beds themselves can be spared any denting by using large area boards to stand on, thus distributing your weight over an area much larger than the sole of your shoe or the area of a knee.

Redhawk

As stated previously, compaction can form from repeated foot traffic in one place. I wouldn't worry about the occasional step but I still would recommend avoiding stepping in your gardens. This can limit the size and spread of pore spaces found in the soil and make plants have to work harder to establish a healthy root system.

Soil Compaction

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I intentionally utilized deeply mulched pathways for my frequently traveled areas in the garden to soften my compaction impact on the soil underneath. I do my best to avoid any needless stepping in my growing spaces. I also do my best to avoid working the soil when it is wet as that is a quick way to cause compaction. I have dealt with soils that have developed crusting and it can be a bear to correct so avoidance is key for me.

Soil Compaction

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