>> There are black clay areas here that are rich for row crops. It is often called "15 minute soil". That is the amount of time that you have to work it between it being too wet and too dry.
:iagree:
For a few years, I thought that you needed a mattock AND a pick to work heavy clay, "because it's rock-hard until you add enough compost". Or paper, or sawdust, or leaves, or grass.
DUHH.
Finally someone explained to the sweating idiot that it needs A LITTLE water to soften it.
DUHH.
The right amount of water softens the clay and lets you break it into smaller clods to mix with organic matter. I could even force it through 1/4" hardware cloth.
However, many year ago, I worked some clay-ey soil when it was TOO wet. It was soggy enough that it slumped together and stuck to itself, squeezing the air out. You know the dry lake bed at Edwards Air Force Base? It got hard enough to land military jets on.
Once I have it just soft enough to work, I try to mix in as much organic matter as I can buy, borrow or steal, plus a little something gritty like crushed stone or bark fines. Then maybe a little coarse sand, like powdered sugar on gummy candy to help keep it from sticking to itself.
Then I "fluff it up" with a garden fork and think airy thoughts, like making a souffle.
Then (I THINK this last step is important), I firm it back down carefully, aiming to get it firm enough that a little rain will run through it instead of turning it to pudding, then soup, then solid-as-rock clay-crete. I try not to firm it down so much that I squeeze all the air paces out.
That step is where I imagine that the grit and sand help the clay-compost mix settle into "structure" with some open spaces, instead of slumping and oozing back into one homogenous pudding.
That's just my theory or daydream, but it either does work a little on my soil in my climate, or I imagine that it does. I have to "fluff it up" once or twice per year until it accumulates enough organic matter and roots and soil fungi to support itself.
LOTS of compost, paper, sawdust or bark fines is sure to work. If you don't have enough organic matter (like 50-50 clay and compost or richer in compost), I THINK the grit and sand help a little.
