The study looked at how changing the grazing time of cows on wet soil days can reduce greenhouse gas emissions on dairy farms. By using a computer model, the researchers found that reducing grazing time on wet days can decrease nitrous oxide and methane emissions by up to 12% on poorly drained soils. However, this approach may not work for farms on imperfectly drained soils, where emissions actually increased. The most cost-effective option was to graze cows for 13 hours on wet days, especially if there were many wet days in a year.