NMU makes good use of wood ash

MARQUETTE – Northern Michigan University is repurposing wood ash from its biomass facility to enhance soil instead of letting it sit in a landfill.

Wood ash is high in pH, so it can act as a liming agent and neutralize acidic soil. U.P. farmers often buy lime to improve their soil and increase their crop yield, so it made sense for NMU to transport the wood ash from its Ripley Heating Plant directly to a farmer in Chocolay Township who has a permit to apply it on his field as well as a proper unloading and storage location.

If the farm becomes “greener” and more productive because of the ash, that could bode well for other farmers.

“This is early in this project,” said Gisele Duehring, associate director of facilities at NMU. “We’re still determining how to best distribute this to the people who really use it.”

Wood chips are processed at the facility, which opened this year.

“This is a waste product from saw mills,” Duehring said. “We’re not felling trees.”

Wood chips, she noted, are an alternative fuel source different from petroleum-related ones, such as fuel oils and natural gas, to provide economic diversity regarding fuel bills – “the biggest expense in generating steam and electricity.”

Duehring stressed wood ash is not a fertilizer but instead complements nitrogen and helps crops absorb nutrients from the soil. She said wood ash from the biomass facility, located on Wright Street, has been found to be safe for agricultural purposes. In fact, Duehring said there might be ways to explore using it for sandy areas at the NMU Golf Course.

However, Duehring mentioned how a farmer stores the wood ash is important because factors such as runoff come into play.

“You wouldn’t want to put a pile next to the swamp,” she said.

Curt Goodman, Marquette water/wastewater superintendent, oversees the city’s biosolids program, which recycles organic material derived from wastewater treatment to improve soil quality. He was determined NMU should not dispose of a usable product, so he offered to foster the connection between the university and agriculture.

“It’s a goal to utilize any byproduct for sustainability and always look outside the box for ways to reduce costs,” Goodman said in a news release.

NMU student Eric Martin became involved in the effort on the advice of his Freshman Fellow adviser Suzy Ziegler, head of the earth, environmental and geographical sciences department.

Martin helped Duehring apply for the liming license and helped Goodman research alternative uses for wood ash and biosolids.

Martin, a sophomore majoring in environmental science, said he and Goodman brainstormed how an experiment could be set up to combine biosolids and wood ash and test the effects on soil remediation.

The goal was to create test plots behind the wastewater plant and compare the growth of crops in soil amended with biosolids, wood ash and combinations of the two to determine the ideal ratio for the best soil.

Although they weren’t able to finish the research, Martin said he might take it on as a senior project.

“This topic interests me a lot because I always like to see what would normally be a waste product being turned into something useful that also has a lot of value,” Martin said. “I do believe wood ash can enhance crops by conditioning the soil that they are grown in.”

Christie Bleck can be reached at 906-228-2500, ext. 250.