permaculture

["Permaculture West" <permawest@olywa.net>]

        Hi there,
        I'm not from your zone, quite a different one actually - it's not the
twilight zone but close...the Pacific NW.  I've just begun experimenting
with understory plants beneath my nut orchard as well.  I've done some
research into the matter and the following is the synthesis of that
research.  I think most of what I've come up with will be applicable in
Wisconsin, if not it's at least worthy of consideration.

        I have intercropped black alders with my black walnuts.  The alder 
will
fix nitrogen and provide a valuable hardwood when I cut them once the
walnut canopy closes.  We have caged all these trees and soon will be
ranging a couple cows through the area to keep the grass and weeds down as
well as to fertilize the ground.
        With my shagbark hickories I have interplanted eleagnus umbellata 
(autumn
olive).  The latter will also fix nitrogen and attract birds to its
berries.  I will also soon innoculate the alder chip mulch beneath these
trees with Stropharia rugoso-annulata (King Stropharia), a giant mushroom
prized for its culinary virtues.  The mushroom culture is an experiment in
nutrient fixation and release from the woodchip medium. 
        I have also been broadcasting crimson clover and vetch on the bare 
soil
and/or mulch around the newly planted nut trees.  Once they've flowered
they're absolutely beautiful.
        A nut orchardist near me is ranging sheep beneath most of his trees.  
By
their nature they are grazers rather than browsers so will manage the grass
and weeds but leave the trees alone. 

        Let me know what other information you come across.  I have a small 
grove
of chestnuts that I've yet to decide how to fertilize or manage as a
polyculture.