ASHLAND — The old adage “the best time to plant a tree was 20 years ago; the second-best time is now” is a favored saying among some financial consultants and other professional advisers. The idea is to get things started now to achieve goals a few decades down the road. But when it comes to actual tree planting, new hybrid varieties can help landowners enjoy the benefits of trees in a fraction of the time.
“Find the right tree for soil conditions and the response is amazing,” said UW-Extension’s Jason Fischbach.
Whether it’s an erosion buffer, windbreak or agroforestry project, recently developed hybrid trees may fit right into future land management plans, while providing habitat benefits to local wildlife. Fischbach, a food and energy woody crops specialist, has spent eight years working with some 70 genotypes of hybrid poplar, willow and tamarack in northwest Wisconsin. Test plots in Ashland, Bayfield and Washburn counties feature a variety of soils, along with some unique growing conditions near the Lake Superior shoreline. The right tree in the right spot produces growth of up to 8 feet a year.
“There are a lot of possibilities with the variety of species available,” Fischbach said. “Trees can be financially valuable to farmers as a crop and as a way to improve soil quality and prevent erosion.”
When UW-Extension and its research partners outlined the hybrid study a decade ago, fast-growing trees were expected to provide woody biomass for Xcel Energy’s Bay Front Power Plant in Ashland. The facility had burned wood to generate electricity since 1979 and engineers were exploring the feasibility of eliminating fossil fuels from its production mix altogether in favor of biomass. Then, in 2012, the price of natural gas tanked, making the fuel very inexpensive, Fischbach said, and applications like agroforestry and conservation became a more immediate destination for project cultivars.
“The goal with agroforestry is to plant other crops in between tree rows,” Fischbach said. “Trees like hybrid poplar make good pulp for paper. Willows work very well as a snow fence and really stabilize the soil. You’re not going to get any runoff.”
A cross between native Eastern cottonwoods and other poplar species from far-off places like Japan and Russia, UW-Extension’s hybrid poplar clones were sourced from researchers in Minnesota; the willows originated in New York. Fischbach said hybrid poplars became a target of the Earth Liberation Front at the turn of the century, when the group mistakenly thought the trees were the product of genetic engineering. Believing the trees would harm the environment, the group torched research plots in the Pacific Northwest on private property in Oregon and at the University of Washington.
“Hybrid plantations on a big scale could pose a risk to wild poplars in some areas, but it’s highly unlikely, as these hybrids are basically crosses within cottonwood,” Fischbach said. “With agroforestry, hybrid trees are part of a planned system that includes more traditional grain or forage crops and even livestock. Sometimes it seems we have a debate that land is managed for either crop production or full-on restoration of native ecosystems. Agroforestry is a middle ground between the two where we can produce crops for income and improve soil quality and wildlife habitat.”
With an interest in local birds, Northland College Professor Katie Stumpf found that at least 16 different avian species utilized UW-Extension’s hybrid tree plots. Over the two-year study, song sparrows and black-capped chickadees rose to the top as the two most visible birds.
Still, landowners can bypass hybrids altogether and achieve their goal of fast tree growth with native tamaracks on some sites, especially clay soils. With deer numbers perpetually high in farm country, fast-growing tamaracks may be an ideal tree.
“Deer don’t touch it,” Fischbach said. “It’s an attractive tree that turns yellow this time of year and does really well in clay.” Tamaracks look like a classic evergreen throughout summer, but the needles turn a distinctive bronze color in October and fall off. Fischbach described the wood as very dense and rot-resistant.
Both hybrid and native tree seedlings are available from local nurseries as well as by mail order. For more information, visit http://wisconsin biomass.weebly.com/lake- superior-woody-biomass- trials.html.