permaculture

[Toby Hemenway <hemenway@jeffnet.org>]

Title: N-fixing desert trees (was: Re: all theory thread DESIGN PRINCIPLES)

on 8/28/00 12:13 PM, Scott Pittman at pci@permaculture-inst.org wrote:

The ideal plant would have a high broad canopy, fix nitrogen, have grey green or silvery foliage to resist ultraviolet, provide light shade, and be drought tolerant. 

Scott: You're in what, USDA Zone 5-6 or so? I assume you've looked at that native invasive, mesquite. You could check Laburnum; and there are some Albizias that are hardy to Zone 6 and maybe Zone 5. Both have open canopies, and can take drought once established. And some big shrubs: Hippophae rhamnoides (sea buckthorn) gets pretty large and is drought tolerant, has an open canopy of grey leaves. Colutea arborescens (Bladder senna) is very tough and drought tolerant. And I would think that caragana would do, though it might not get as big as you want. Various brooms (Spartium, hybrid Cytisus x spachianus [a non-invasive type])? The Bullocks up in Washington use tall shrub canopies for nurses, and they only get 16 inches of rain, though they irrigate to get things going.

A nice, thoughtful post, BTW.

Toby