Evaluation of the impact of residential fertilizer application and use in the Chesapeake Bay Watershed

Dr. Gary Felton is the PI. The sponsor for this project is the Maryland Chesapeake Bay Implementation Grant with funding at $ 25,000. The duration of the project is July 1 2005 – March 31, 2006.

This project produced a critical synopsis of the current literature on the relationships between residential fertilizer application and nutrient loads. The synopsis focused on activities in Maryland. Some findings included that Maryland has approximately the same acreage of turf as acres of fertilized crops. Nitrogen is seldom if ever lost through runoff from turf but rather is moved by infiltration and leaching. Only approximately 10% of homeowners use a lawn care company. Fifty percent of homeowners do not apply any fertilizer to their lawns. The average number of applications by homeowners is between 1.6 and 2.8 per year. The average application is between 1.6 lbs N/year and 2.8 lbs N/year, well below that MCE recommendation of 3 lbs N/year. For numerous reasons, MDA fertilizer sales data are not appropriate for nutrient accounting.

Research gaps exist concerning impacts of homeowners on water quality. Amounts of fertilizer left on pervious surfaces have not been investigated. Impact of sweeping has not been quantified. Nitrogen and phosphorus loss through grass clippings is unknown.

Policy attention has migrated to things that we know can make a difference. Off-target application is an example.

For more information, contact Dr. Gary Felton

Last updated: 02/6/2008