Sediment Reduction with Organic Farming

Douglas Romig (deromig@students.wisc.edu)
Thu, 4 May 1995 11:19:20 -0500

A colleague of mine in the WI Sustainable Ag Program posed a question to me
that she had recieved from a member of the Oneida tribe. The tribe wishes
to start an organic farm in a priority watershed (ie concerted effort by the
state to improve surface water quality). They need to make the case to
state officials that organic methods won't jeopardize water quality, a case
stronger than what the consultant from the organic certifier provided (based
in some research I gather). The specific question was: "On clay soils, do
organic farming methods reduce the amount of sediment reaching surface water?"

As a grad student in soils, I am aware that that the addition of organic
matter thru green and animal manures, crop rotations, etc. often improve
soil structure and reduce surface crusting. These improved surface
conditions could lead to increased infiltration rates, while reducing runoff
and sediment load to streams. I am also aware that erosion can happen just
as easily on an organic farm as it can on a conventional one. And of course
there are many confounding factors (at least for scientific inquiry) with
respect to various management strategies that influence erosion and they may
have more significant impacts than the nature of the inputs. Despite the
complexity of the issue, has there been any research that has has examined
the relationship between sediment delivery to surface water and organic
farming methods?

Thanks in advance,

Doug Romig
UW-Madison