A New Leaf: Making Paper From Weeds
An invasive ecological bad guy may be able to paper over his evil ways and absorb some carbon as well.
The giant reed (Arundo donax) is mostly green. It's a weed that looks a lot like bamboo.
Native from the Mediterranean to India, the enormous grass colonizes stream beds of the coastal United States. Growing in wetlands, it chokes out native plants, threatens animal life, is a fire hazard and poses problems to existing infrastructure such as bridges. The Plant Conservation Alliance has added it to its "Least Wanted" list.
"There's a reason for almost everybody to hate it," said Jeff Beehler, senior environmental project manager of the Santa Ana Watershed Project Authority in Riverside, Calif.
But there are a few folks who don't hate it. In fact, they see potential for its rapid growth.
Since arundo is a rapid renewable resource — literally growing like a weed — it is a promising non-wood source for paper. The big advantage is that it grows fast and produces a lot of material. It grows so well, in fact, that there are accounts of green shoots 6 to 8 inches tall, pushing their way through the still smoldering ground soon after a fire. With its rate of growth and its size (easily reaching the height of a two-story building), the biomass production per area of land is astounding.
Producing paper with 100 percent arundo had been the vision of the late Ernett Altheimer, who founded The Nile Group in 1996 to work with alternative fibers.
The department of paper science and engineering at the University of Washington is the world leader in alternative fiber research. Professor Mark Lewis has been doing research at the university for 10 years and worked with Nile as its technical adviser.
Together, they had two successful trial runs turning arundo, harvested from a California eradication effort, into paper. "We found it to be a superior plant material, more than anything else we've seen. It runs similar to wood," Lewis said.
There's another benefit to the weed in an era of climate change. "It's one of the largest, fastest biomass producers and will sequester carbon 15 times more per acre than Douglas fir trees," Lewis explained. "And, it can be grown in most areas in the U.S." — meaning that growing the weed en masse may reduce greenhouse gas emissions.
Adding to its eco-friendly attributes is a decreased processing requirement with a 25 percent savings in terms of both energy and chemicals.
And there are potential economical benefits. Since the bulk of paper comes from construction and plank remnants, wood chip prices rise at a time of reduced housing growth. For the paper industry, having a steady supply would secure a fixed cost despite market changes.
In the Santa Ana project, "Their taking material is a win-win in that it reduces disposal cost," Beehler said, although that seems to be but a short-term benefit given the purpose of eradication.
With several acres yet to be removed and the eradication effort half finished, there is no intention of letting arundo grow back. "I'm looking forward to the day that we can get to the ocean and be completely arundo free. If all goes well, we won't be suppliers for The Nile Group," Beehler said.
That's OK, because arundo's sheer mass presents another challenge.
"We gathered 400 tons of chips," equivalent to eight rail cars, Lewis noted. "Harvesting out of the wild is not economically viable — it's not cost-effective to ship it."
Having an arundo plantation near a paper mill is the answer. So farming the weed is the route the company, now called Nile Fiber Paper and Pulp Inc., is taking. "Sometime next year we have some strategic alliances that are desirous of planting it next to a facility so transportation won't be a large cost," said Ben Altheimer, Nile member and Ernett's nephew.
The current commercial use of arundo has been in the production of reeds for wind instruments. It is a small, limited market but shows that arundo can be cultivated without posing problems as an invasive plant. Keeping it away from water-drainage areas is an important factor in controlling it.
As Beehler warned, "One person's crop is another person's invasive weed," although "there may be places where it's appropriate."
"We have an existing plantation in eastern Washington. And the plantation has not moved outside the borders," Lewis explained.
While paper science and engineering students at the University of Washington make a completely non-wood paper containing arundo for the purpose of fundraising, it is not yet commercially available.
"We make it here at the university on a small scale for research or for the companies that have been working with it. We're also working with a couple of paper companies that are looking to run major trials, and hopefully it will be available," Lewis said.
"Our intent is to have copy paper, but there are other (paper varieties) that we are also looking into," Ben Altheimer added.
"Stay tuned. We have quite a bit of work that is to be done as far as a larger commercialization program."