I can't find an area specific layout in which I can relate to. I got about 4 ft down so far. My goal is China by the way.. just kidding
I've hit gray clay like stuff.

A hugelkultur bed does not have to be humped up into the air. It can fill a trench just as well.

Nono, I was wondering geographically... what comes after below this

You can find soil surveys online for your area. I had found one for IN which was really interesting. I think it was through Purdue but can't remember exactly.

Yeah MSU has one but it is too complicated to understand

That gray stuff is about 2.5-3 feet down in my garden. Clay.
And if you go lower..it stinks. Impossible to dig through. China will just have to come to me.

Brenden - I did manage to partially wade through the soil survey for my section of IN - reading it online and googling terms, etc that I didn't understand. Of course, it will depend on how much backfill the builder used around your house. Clay is preferred for backfill around house foundations because it helps stabilize it.

Brenden, you could ask your local extension office, they should have more idea. The soil horizons can very from place to place even in close proximity, so I don't think anyone here can tell you what's underneath the clay. You were able to dig down far further than you would have been able to where I am, you'd have hit rock by now in many cases.

Just out of curiosity, why are you digging down that far?

>> Brenden, you could ask your local extension office, they should have more idea.



Here's MI extension contact info by county:
http://msue.anr.msu.edu/county


I think you would need a finer map than just "county" to find what the deeper soil horizons are, right where you live.

But if that gray layer is clay, it doesn't matter very much to gardeners what's underneath it. Since water won't penetrate it very fast, rain water will run off according to the slope of the permeable layers above the clay.

Since oxygen can't penetrate it very well, it will have little soil life and no roots growing down through it. So it could be bedrock, sand or green cheese, as far as your plants are concerned.

Maybe just check with neighbors, maybe they have had cause to did down deeper and know how deep the clay is.

When the reservoir for our pondless streamwas dug...that grey stuff seemed to go on forever...it was useful to create the bank/ side wall for the stream...in it were huge rocks...abundant enough to make me wonder about radon in the area. i checked that out and looks like we would have to go further west to encounter that issue.