By: Louise Calderwood, Northeast Agribusiness and Feed Alliance
The smell of fall is upon us; ripe apples, wood smoke, fallen leaves and….manure! Wait-manure-that doesn’t fit this list of wholesome odors, or does it? Why do farmers spread the sloppy liquid? Aren’t there ways for farmers to manage manure from their livestock that reduces the impact on roadways and water?
Chris Wagner of Green Dream Farm in Enosburg Falls, Vermont is one of a growing number of farmers turning to new ways to manage manure. Wagner milks 375 cows and supplies milk to St. Albans Creamery who in turn supply Ben and Jerry’s Ice Cream. Until the spring of 2014 he managed the 3.4 million gallons of manure and wash water produced each year on his farm by using large lagoons to store the liquid until it could be spread on fields used to grow forages for the dairy herd.
“Manure is a valuable resource for our farm,” Wagner said in a recent interview. “We hire a custom machine operator to spread it according to a management plan developed specifically for our fields.”
With financial assistance from NativeEnergy, a Vermont based renewable energy technology company, Wagner installed simple screw press equipment to separate manure solids from manure liquids. The solids are composted and reused as high quality, sanitary bedding for his cows. Excess solids are sold to other farms for bedding creating a moderate income stream for Wagner.
“The cows really like the composted bedding,” Wagner said. “It is super absorbent and very comfortable for them to lie on.”
Wagner recognizes the potential for manure to pollute water if it runs off farm fields and into rivers and streams. Phosphorus carried in the manure causes algal growth that robs the water of oxygen needed for aquatic life and can lead to blooms of toxin producing blue-green algae.
“I am part of the community,” Wagner said, “protecting water quality is everyone’s job, not just the farmers.” Wagner recognizes the obligation he has to protect water quality, “I manage a lot of land so I have more of responsibility to be careful about runoff.”
The Green Dream Farm Methane Reduction Program recycles phosphorus on the farm in the composted bedding, reduces the volume of manure that moves over roadways, and reduces methane emissions from managed manure. Extracting the solids and spreading only the liquid portion of the manure reduces the amount of phosphorus applied to the fields by 20% and reduces the total cost of manure spreading.
In addition to the manure separator, Wagner protects water quality by managing liquids released from stored feed and maintaining buffers of grass with no manure or fertilizer application between his fields and water ways. “I test the manure and soil to be sure the right amount of manure or fertilizer is spread on each field.” Rye is planted on cornfields in the fall to hold soil in place during the winter months. Wagner is also considering farm changes to protect water quality, “I would like to plant more of the farm to grass,” Wagner said; the potential for soil run off is very low from grassed fields. He said “I am looking in to applying manure directly into the soil or close to the ground with a nozzle.”
Some farms manage manure with bacterial “digestion” to reduce odor and capture methane to burn for electricity generation and others are composting directly in the barn through the addition of large volumes of bedding under the cows.
One theme is constant across all livestock farms: manure is money and farmers don’t waste it. It is clear farmers recognize their role in protecting water quality and appropriate manure management.