Hey Jennifer,
I suppose I used the wrong term, didn't I? Can't have much of a swale if you don't have an elevation shift (which I really don't). I suppose infiltration ditch would be a better way to describe what I am trying to dig with the trencher.
Here's a keyboard picture of what I want to do:
===16" deep trench, 12" wide===
---drip irrigation-------------
--------trees------------------
--------5 ft wide berm---------
-----------drip irrigation-----
====Mulched over trench========
I'm in the high desert region of CA, Mojave Desert. 1000 chilling hours, average annual low 15F, Annual rainfall at 10" or so, all in the winter.
My long-term plan is to cover the whole place with trees. I want to try and stack an orchard on top of a pasture. I want to collect rare fruit and have a collection of all the best temperate and desert fruits from around the world.