The EPA announced last week that it will allow year-round sales of gasoline mixed with 15 percent ethanol, known as E15, just in time for the summer driving season. Traditionally, gasoline is blended with only 10 percent ethanol except during winter months when it gets increased to 15 percent. The higher ethanol blend was only allowed during the winter months due to concerns over smog at high temperatures, a concern biofuel advocates say is unfounded.

Removing the ban on sales of E15 during the summer months marks a victory for corn farmers and ethanol producers who have been trying to get the change for many months.

The National Corn Growers Association says ethanol accounts for about 30 percent of U.S. corn demand. A year-round E15 blend is sure to boost corn prices in the long term.

According to the latest NAAA industry survey, aerial applicators treat approximately 9.4 million acres of corn and 5.7 million acres of soybean each year. This is a healthy increase from the 2012 industry survey, which showed aerial applicators treated 7.8 million acres of corn and 4.4 million acres of soybeans. Additional crops used in advanced biofuels include sugarcane and canola.

The rule is expected to be met with legal challenges from the fossil-fuel industry, which claims allowing E15 sales during the summer months is against the Clean Air Act.

The EPA said the change is not only legal but required as Congress mandates 15 billion gallons of ethanol be absorbed into the gasoline market each year. Due to waning gasoline demand, the Congressional mandate would not be met at reduced E10 levels.

The EPA also released data showing how E10 and E15 perform at similar levels in cars made after 2001, allowing the agency to legally treat the two fuels the same.