We are relying heavily on voluntary action by land users and prefer this approach over the straitjacket legal approaches. The question is: is this approach working?

Two years ago USDA-NRCS released an assessment of the effects of conservation practices on cultivated cropland in the Chesapeake Bay Region. It was the second in a series of regional reports (the first covered the Upper Mississippi).

The reports use a sampling and modeling approach to quantify the environmental benefits that farmers and conservation programs provide to society and how these can be expanded.

The findings of the report were encouraging - they showed that the voluntary, incentive based conservation approach is working: Nearly half of cropland acres were protected by one or more structural practices such as buffers or terraces, no-tillage was used on 48% and reduced tillage on 40% of cropland.

The adoption of conservation practices resulted in 55% reduction in edge-of field sediment loss, 42% reduction in surface nitrogen losses, 31% reduction of subsurface losses of nitrogen, and 41% reduction in phosphorus losses (both sediment-bound and soluble).

Implementation of the BMPs reduced total loads from all sources (including urban, hay and pasture, urban land) delivered to the Chesapeake Bay by 10% for sediment, 14% for phosphorus and 14% for nitrogen.

The report also recognized there was potential for further improvement, especially on 19% of cropland which was in need of further conservation treatment. The report recommended targeting these areas of highest need, and to help land users implement comprehensive conservation plans which cover soil erosion control and comprehensive nutrient management (including rate, form, timing and method of nutrient application).

The report estimated that only 4% of cropped acres used cover crops in the period of assessment (2003-06). It was estimated that adoption of cover crops on all cropped acres could reduce sediment loss further by 59%, nitrogen loss by 19% (subsurface loss by 31%), and phosphorus loss by 32%.

It is encouraging to see that the voluntary conservation approach is working and that the practices we are exploring and promoting will have a very beneficial effect on water quality in the Chesapeake Bay.