Improved water quality in the Chesapeake Bay has been a long-term concern in Virginia and other Mid-Atlantic states. Winter annual cover crops are an important tool for water quality protection because they can scavenge and utilize soil nutrients, especially nitrogen (N), which could otherwise be lost from the soil/plant system through leaching and runoff during winter months. Experiments were conducted at one site in the central Coastal Plain of Virginia in 2005-2007 to evaluate the effects of winter cover crop species and planting date on soil cover, total biomass, crop N uptake, and change in soil nitrate. The trial was also used to educate producers and agricultural professionals on how to successfully implement cover crops to maximum environmental and economic advantage. Rye and rye + hairy vetch planted either early or mid October yielded significantly more biomass than other species. Nitrogen uptake was > 150 kg ha-1 for rye in 2005 and hairy vetch alone in 2006 but was < 100 kg ha-1 for all other species. Oats and barley provided the least N uptake. The addition of spring nitrogen significantly increased N uptake and biomass across all small grain species especially at the early and mid planting dates. In 2005 the early and mid plantings reduced soil NO3- level by 30 kg ha-1 across all species compared to the later planting date. February soil NO3- levels were significantly lower under rye, across all planting dates in 2005. In April there was no difference in soil NO3- levels among small grain species. The 2006 soil NO3- results showed similar trends to 2005, but were not significant. Small grains and winter annual legumes make good winter cover crops that help reduce soil erosion, trap unused nutrients and improve soil quality by producing biomass that increases soil organic matter.