Rother, a forester with the U.S. Army Corps of Engineers, was clearing away reed canary grass — an aggressive plant species that has invaded the forests and wetlands along the upper Mississippi.

A long-term research has revealed that reed canary grass can be turned into an excellent ‘green’ fuel for biomass power stations and, on a smaller scale, boilers in buildings like schools.

Soon, the spray fields will be green with reed canary grass. “When I started work here 15 years ago, I never thought I’d be a farmer,” said Steven Miller, Manchester’s water and waste ...