Middlebury

 

Willows for Biomass - Test Plot Planted

May 16, 2007

 

Willows for Biomass? Ten Acre Test Plot Is Underway


A new crop is growing in Addison County. The College recently planted 10 acres of farmland to the west of campus with willows in an experiment to see if willows are a good choice for a sustainble supply of wood fuel.

In looking for options to meet our need for 20,000 tons of woodchips per year for our soon to be woodchip gasification heating and cooling system, one that looks promising is the possibility of growing biomass on fallow farmland in Addson County. Last summer Tom Corbin, Director of Business Operations and Jack Byrne, Campus Sustainabilty Coordinator toured an experimental willow shrub plantation in northern New York operated by the SUNY College of Environmental Science and Forestry. Central-northern New York was historically an abundant producer of willows for the basket making industry and there is interest in reviving that practice for energy production.

We recently established a joint effort with Dr. Tim Volk and colleagues at SUNY-ESF who has years of research experience with willows to conduct a pilot project on 10 acres of college land to the west of the campus.

We will plant 30 different varieties of willows this spring at a density of about 6,000 willow whips per acre. After the first year of growth the plantings will be coppiced, i.e., cut back to the base to force the growth of more branches. They will then grow for another two years reaching 15 to 20 feet in height. In the fourth year they will be cut and chipped for use in the biomass burner. The regrowth from the willows will be harvested annually for up to seven years thereafter.

Harvest will be done with standard corn harvesting equipment using a modified cutting head. Yields of around 25 to 30 tons per year per acre at 45% moisture content have been obtained in the New York trials. The results of the pilot and the lessons learned will be shared with agricultural landowners and farmers in the region with the hope that they would eventually go into business producing willows for energy. The pilot project will also look carefully at how to minimize or eliminate the use of fertilizers and pesticides in the cultivation of willows.

A look at the willow planting operation that took place on May 15, 2007.

One section of the ten acre site is being hand planted with 30 varieties of willows. It’s divided into four subplots, each planted with the 30 varieties. Each subplot will be treated differently by the SUNY-ESF research team to test how different treatments affect productivity.  

The other, larger, section is being machine planted with four varieties.

Click here for a look at the planting operation
(requires QuickTime viewer)

What it shows:

The first set of frames shows the willow planter doing a pass. Willow whips are fed manually into four planting tubes. They are cut into 8” pieces and inserted into the earth. Four rows are planted with each pass. The row spacing is configured so that the harvester will be able to drive through the willow growth and do its cutting when that time comes.  

The last few frames show a bag of willow pieces that will be hand planted and a couple of shots of the SUNY ESF crew doing some hand planting.