According to a new study, leftover watermelons from farms’ harvests could be converted into up to 9.4 million liters (2.5 million gallons) of clean, renewable ethanol fuel every year destined for your car, truck, or airplane’s gas tank.

Agriculturally, watermelon is a peculiar fruit — each year farmers across the country leave between 20 and 40 percent of their crop to rot on the ground.

“If a crow lands on a melon, takes two pecks at the rind, and then flies away, it’s no good,” Wayne Fish of the United States Department of Agriculture in Lane, Oklahoma said. “I had farmers telling me, ‘I’m leaving one-fifth of my melons on the land. Is there anything I can do with them?’”

Some local growers wondered whether the waste melons could be turned into ethanol, the clean-burning fuel derived from plant sugars. In a series of new experiments published yesterday in the journal Biotechnology for Biofuels, Fish and a team of researchers showed that they can.