Subject: Re: [permaculture] Looking for good examples of the use of berms and swales &...
Date: Sun, 15 Jul 2007 11:33:39 -0500
The object of swales is to hold water on the land as long as possible to
allow as much to sink in as will. Observe the land to see how the water
runs off it, then swale in opposition to that flow. If you swale on
level, water sits in the swales until it soaks in or evaporates. Frogs
love these waterholes. If you have to, keep them full enough to allow
the tadpoles to mature as frogs are a sentinel species and if you have
them, you're doing something right. Berms of the soil brought out of
the swales thus stay moist longer. Properly mulched, they never dry
out. The secret is to keep the berms covered with a thick layer of
mulch. Avoid sun contact with the soil, on berms or not, except where
there is enough water to form permanent mud. Plant annuals in the
decomposing layer of mulch, not in the berm soil proper. Trees and
berries with their more extensive root systems need to be planted in the
berm. Shape the berm so the tree or berry sits in a basin that holds
water instead of letting it run off. If annuals need support they can
be staked or caged. Kept moist, clay/adobe berms need no amendments.
Calcium will help to break up the clay if you want to amend, but you're
faced with bringing in something from off-site. Shell flour works, and
comes in 50-pound bags. Broadcast it on the berm before initial
mulching. That's all we did, and I could stick my hands into the soil
of adobe berms up past my wrists in the height of the dry season.
Tommy Tolson
Austin, TX