University of Minnesota trademarks fast-growing poplar tree

DULUTH — It’s been said that the true meaning of life is planting a tree “under whose shade you do not expect to sit,” a hint, of course, that you’ll likely be dead before the tree gets that tall.

But researchers at the University of Minnesota now say you don’t have to wait that long after all.

The university has trademarked a new, rapid-growth tree that not only will shade your lawn and put up a natural fence between you and your neighbor faster than ever before, but a tree that could be a key to cleaning up polluted hot spots, reducing climate change and developing plastics and biofuels from crops other than corn and soybeans.

It’s called InnovaTree and it was unveiled Friday at Hauser’s Superior View Farm just outside Bayfield, the first place the tree is available for the public to buy.

University officials are hoping InnovaTree will become the Honeycrisp of shade trees. Much as university horticulture experts have developed some of the nation’s most successful apple varieties over the last century, researchers at the Natural Resources Research Institute arm of the University of Minnesota Duluth has spent nearly 30 years perfecting the fastest-growing, most disease-resistant poplar in the world.

How fast? Up to 8 feet in a single Northland growing season, some 64% faster than other hybrid poplars and four times faster than many common landscaping trees. That’s taller than a two-story house in just a few years. It will grow to more than 70 feet tall as a mature tree that can live for an estimated 75 years or more.

“The oldest InnovaTrees now are just 14 years. But its mother is a Minnesota native cottonwood, and those can easily grow for more than 100 years, so we’re expecting a really long-lived tree,” said Jeff Jackson, University of Minnesota Extension outreach educator.

Need some quick shade to cool down an urban hot spot amid record-setting heat waves? Rapid-relief erosion control for farm shelter-belts and along streams? Check and check. InnovaTree also is being tested by U.S Forest Service and NRRI scientists for its ability to soak up toxins from polluted hot spots, called phytoremediation, including its ability to absorb sulfate, a byproduct of some mining operations.

Because InnovaTree grows so fast, research shows it can pull toxins out of the ground at a rapid rate. Polycyclic aromatic hydrocarbons, volatile organic compounds and even PCBs and heavy metals can be absorbed and either stored or broken down by the tree’s photosynthesis. And because it absorbs so much water as it grows, InnovaTree is being touted for urban rain gardens where it could slow runoff and help reduce flooding caused by increasing rainstorms.

InnovaTree could even be refined into bioethanol and bio-plastics to replace carbon-spewing fossil fuels. And it could be planted on marginal farmland across the globe to help ease global climate change, absorbing carbon four times faster than a red pine and earning carbon credits for the landowners.

“There’s really nothing else like it anywhere else. Of all the trees they (NRRI staff) worked on over nearly 30 years, this one came out on top,” Jackson said.

InnovaTree is sterile, like a mule, and its seed won’t sprout, so Hauser’s nursery received 25 10-inch cuttings of InnovaTree in 2021 and planted them, with more cuttings from those first trees planted in 2022. This April, Dane Hauser, the fifth-generation owner of the nursery, planted dozens of four-inch InnovaTree cuttings into pots and grew them in a greenhouse. Those cuttings are already 3-5 feet tall and ready for sale.

“For over 20 years, our NRRI team used natural selection and breeding to develop hundreds of poplar varieties in extensively replicated Minnesota and regional field trials,” said Bernard McMahon, NRRI’s now-retired hybrid poplar program tree breeder.

McMahon and other researchers and University officials were expected to gather at Hauser’s on Friday to celebrate the results of their efforts. For each InnovaTree sold, the University of Minnesota will get a royalty, with the money planted back into research.

Jackson was called-in to help market the tree that after its originally intended use cooled.

Pushed by calculations in the 1990s that Minnesota’s natural forests might run short of wood if demand from board plants and paper mills continued to expand, NRRI scientists went to work on hybrid poplars that could be grown on marginal farmland and replace fiber from forests.

But as the number of mills in Minnesota shrunk due to global competition, the demand on the state’s forests diminished, too. Attention then turned to growing hybrid poplars for biomass fuel to replace coal and natural gas. But that market, at least in the U.S., also cooled as coal prices plummeted and debate raged over whether burning biomass was truly carbon-neutral or not.

While the focus has shifted to the consumer market for InnovaTree, there are still potentially large-scale applications for carbon capture and fiber, Jackson noted. InnovaTree is being tested in Europe as feedstock for plants that produce oriented strand board, called OSB, because native forest trees in Europe are in high demand, short supply and very expensive. And foresters in eastern Europe are eyeing InnovaTree to help reforest war-torn Ukraine where countless urban and rural trees have been obliterated by bombs and shells.

Until then, though, it will be consumer purchases for landscaping trees that U of M officials hope will make InnovaTree famous.

“There are currently millions of hybrid poplars being sold in the U.S. for landscaping every year, and there’s no reason this tree can’t capture a big part of that market considering how much better it is,” Jackson noted. “This is not a tree that’s intended for natural forests. … But for landscaping and for phytoremediation and fiber, planted in cities and on marginal lands, we think it can have a really big impact.”

• A cross between native eastern cottonwood and European black poplar, naturally cross-bred over 25 years until the star of the family emerged.
• Resulted from NRRI research, starting in 1996, on 1,672 hybrid poplar varieties from 115 families in 27 field tests at nine sites in Minnesota and sites in several other states. 
• Is not a genetically modified organism but grows from the same, traditional horticulture practices used for apple and other fruit trees. The NRRI established over 45 field sites throughout the Midwest and Northeastern U.S. and has never had an escaped seedling survive outside the planting area.
• Doesn’t sucker and its seeds are infertile, so it won’t become an invasive species problem by spreading into native forests. It’s cottonless, so no fluffy stuff in the springtime.
• Hardiness across zones 3-6 — everywhere from North Dakota, Minnesota and Wisconsin south to Missouri, Kentucky and Kansas.
• Grows best in full sun in well-drained loam, sandy loam, clay loam and light clay soils with annual rainfall above 20 inches.
• Captures an impressive 6.8-8.5 metric tons of carbon dioxide per acre per year. 

A 3-foot potted InnovaTree is $20.

Visit Hauser’s Superior View Farm, 86565 County Highway J, Bayfield; call 715-779-5404; or visit

superiorviewfarm.com

. Shipping is available. It’s expected to be available at several other nurseries in the Midwest next spring.