Willow (Salix species)

 Willows are economical to propagate and fast-growing once they become established.  As a perennial crop, willows can be harvested every 3 years for 20 years.  Their multi-stem shape is better for wildlife habitat than singletrunks trees such as hybrid poplars.  As a biofuel, willows burn hot like hardwoods, and their thin bark assists in fermentation.  

Hybrid Aspen (Populus tremuloides x Populus tremula)

When used as biofuel, aspens are grown in forested areas.  The first harvest occurs after 20 to 30 years and then every twelve years henceforth.  Aspens are self-regenerating; after harvesting, the roots produce suckers that self-thin, making them easy to manage.  Hybrid aspens require less financial outlay and chemical input than other biomass options. Plus, they don't require the use of agricultural lands.

Cordgrass (Spartina pectinata)

   Cordgrass is native to wet prairies, ditches, and marshes.  Though the plant is not easy to establish, it can become a dense, robust grower, reaching 6-8 feet at maturity.  Once established, cordgrass will spread to form thick, vigorous mats of roots.  It has the potential to be a very consistent biomass crop, especially in northwestern Minnesota, where it has been known to yield 5-7 tons per acre each year.

Alder (Alnus species)

Alder can tolerate tough conditions such as saturated, thin, or infertile soils.  For this reason, alders have the potential to be grown on non-agricultural lands, including reclaimed lands: landfills, mine sites, and other disturbed areas.  Alder plants are self-fertile.  They also form root nodules that absorb nitrogen from the air.  Two alder species are native to Minnesota.

Prairies
  Restored prairie grasslands need to be disturbed regularly to prevent invasion by woody plants.  Harvesting is a more cost-effective way to do this than burning is, and harvested prairie species often make good biomass.  Mixed prairie plantings are usually native, which makes them more resilient to Minnesota pests, soils, and climate.  Management costs are further reduced by the fact that several prairie plants are nitrogen-fixers.  Prairie plantings also provide habitat for valuable wildlife, including pollinators.