permaculture

[Mark <mpludwig@facstaff.wisc.edu>]

Thanks for your comments.  I did put this up to sir the pot a 
little.  Ideally of course we reduce the need for annual crops like 
beans.  A few comments follow...
At 05:30 PM 3/25/02 -0500, you wrote:
> Setting aside the issues of genetic manipulation

I worry about this with species that have close weed relatives like rape 
(cannola)  I also was highly opposed to the initial release of GMO crops, 
but have accepted some of them as OK (RR beans) while still being quite 
opposed to others (BT anything, any micro-organism).  These things need to 
be looked at case by case IMO.

> and runoff pollution of
> excess glyphosphates, yes, the farmer uses a lot less fuel with Roundup ready
> seed : one trip to spray, one to plant and one to harvest. Forty years ago it
> took two or  three trips to prepare the seedbed, one to plant, cultivate
> three times, then harvest.  Planting in last years' crop residue has
> dramatically reduced tillage and helps conserve topsoil.  Roundup ready
> soybeans have "clean fields", and increased yields, but how much energy is
> conserved when all of the processes involved in the extraction, manufacture,
> handling of manufacturing byproduts/waste and transportation  are included ?

Inherent in annual commodity ag; I think we need  a local foodshed 
paradigm, this is only possible if people actively seek to consume local 
products; a somewhat daunting task....

> An analysis of this question would make a good subject for an agricultural
> economist.

Agreed.

> Organic fertilizers should be of a local source where ever possible if you
> are truly working towards a "permanent" , "sustainable" agriculture. Granted,
> some minerals may need to be imported, but nitrogen is a local source
> nutrient -- plant legumes if you can't process dried forage thru livestock.
> Again, look at the total energy budget issues.

N is the easy one, the rest is quite a challenge; though it is quite 
amazing what gets disposed of by industry (watch out for heavy metals of 
course).  Keeping pH neutral or lower helps with trace mineral 
availability, and of course good rotations can increase availability of 
minerals.

> I must agree that using glyphosphates to burn down turf can be useful,
> however, some additional cultivation of the soil is required to make a
> seedbed, as generally soil under turf in clay soils is compacted .

You can follow on with narrow strip tillage.  Clay can be a 
challenge.  Supplementing Ca, S and OM is quite helpful.  The trouble with 
tillage on clay is that once you compact it (esp while too wet) it's really 
like a brick.  Sure like that CEC though....

> Currently, it seems to take less human hours to turn turf into garden space
> using glyphosphates, but also consider the sheet composting/mulching method,
> which requires forethought at the end of the prior growing season and adds to
> humus and soil building.

I working on living mulches, white clover and black medic.  Hopefully the 
glyphosphate is used infrequently.

> Glyphosphates are probably best suited to a limited role in eradication of
> "noxious weeds", when you can't use goats.
>
> Sara in IN

Oh I'm a real sinner, I'll even break out the 2-4-D and garlon for the real 
pesky weeds.

Mark P. Ludwig
Poultry Research Lab
University of Wisconsin -Madison
608-262-1730 WK
608-846-7125 HM