geology, rocks, and arils (was Re: Region 7 potluck & arilbreds
- To: Multiple recipients of list <email@example.com>
- Subject: geology, rocks, and arils (was Re: Region 7 potluck & arilbreds
- From: LMann76543@aol.com
- Date: Wed, 26 Feb 1997 04:51:04 -0700 (MST)
In a message dated 97-02-23 20:41:58 EST, you write:
>I'm interested in growing a few arils/arilbreds myself. Would they do
>well in my part of Zone 7 (on the border of Zone 6)? I also have a lot
>of bits of rock just a few inches down in my soil - I think it's shale
>maybe - is shale anything like chert?
I can't comment on your climate, but when they say chert beds, they mean rock
piles. I would say at least 50% rock fragments (up to 80%), with the
fragments ranging from 8 inch rocks to almost sand grain size. If I put a
shovel of my garden 'soil' through a screen with 1/4 inch openings, more than
half won't go through in most places.
I was hoping somebody who knows about geology would answer your question but
I will take a stab at it - keep in mind I don't much know what I am talking
about on this one. Shale is usually a soft rock composed of sedimentary clay
or silt that has been compressed into a semi-hard state but not metomorphized
(is that a word?) by high enough temperature and pressure to turn into 'real'
rock. If it is at the soil surface, it will weather fairly rapidly into clay
or silt. Chert is a silica based hard rock that comes from ..... I don't
know what. It's what's left when softer, more readily weathered stuff is
weathered to clay. So I suspect shale would not provide the kind of 'sharp'
drainage that chert does.
Linda Mann firstname.lastname@example.org east Tennessee USA
apologies to geologists