Lichtenberg, ErikParker, DougLawley, ChadDr. Erik Lichtenberg and Dr. Doug Parker of the University of Maryland, along with Dr. Chad Lawley of the University of Manitoba, studied the content of nutrient management plans written before they were required by law to see if that content varied according to the type of provider.en-USnutrient pollutionnutrient management plansfarmingfertilizerMarylandTechnical Report