Making Better Choices in a Finite Environment
Can we have our natural resources cake and eat it too? Not until we begin making better choices. University of Minnesota researchers have investigated questions of life cycle analysis of products, helped industry produce more with less environmental risk, helped consumers make better decisions, and discovered new products and processes that lengthen the life of products made from wood. U of M researchers are also helping resource managers and land-use planners make better decisions by understanding the myriad social, ecological, and economic aspects of environmental issues.
Pioneering research by University faculty advanced the wood preservation industry in the United States and helped Minnesotans find commercial uses for their timber. By 1929, Minneapolis-St. Paul was described as the largest utility pole distribution and treating center in the United States. Studies in wood preservation continue to improve the serviceability of wood, saving trees, and saving budgets.
University research in moisture properties of wood is world-renowned. Basic research on the movement of liquids through wood provided the basis for closely related studies of the effects of chemicals and high drying temperatures on the strength of wood.
Researchers demonstrated in the 1970s that it was possible to make wood-like panels from such raw materials as cornstalks, wheat straw, and sunflower hulls. Processes that incorporate wheat straw into structural and nonstructural panels have recently begun to be commercialized in the Upper Midwest; perhaps marking the beginning of a major new industry based on agricultural residues. More recent research in the College of Natural Resources has examined the potential for using some of these agricultural by-products to supplement the use of wood fiber in paper production.
U of M scientists also shaped wood science and technology education through the publication of the world's leading textbook in the field, Forest Products and Wood Sciences, now in its 4th edition.
Wood Project Ingenuity During WWII
The wood gliders and training planes of World War II are fragile antiques today. But during the war they met a need and were an example of wood product ingenuity and research.
At the outbreak of the war when the U.S. needed planes but lightweight metals were in short supply, University of Minnesota researchers working at the U.S. Forest Products Laboratory in Madison, Wisconsin, helped retool the furniture industry to meet the need.
The average glider carried 15 people and their equipment or a vehicle. Built with one-eighth-inch wood veneer skinned wings, they were lightweight, inexpensive, built from material readily available, and suitable for landing troops under cover of darkness.
The phenolic resin glues and techniques developed then are used today in waferboard and other wood products. Wood veneers were also impregnated with phenolic resins. The resin-impregnated wood was compressed to the density of a soft metal and used like metal. After the war, it found use in golf club heads, knife handles, and in tennis racket frames. These advancements help extend our previous wood resources.
And a compliment was paid to U of M researchers when billionaire Howard Hughes asked them to conduct a feasibility study of building a fleet of planes similar to his giant wood airplane known as the "Spruce Goose." However, plans were scrapped when a cost-benefit analysis concluded it wasn't practical.
Supplemental Uses for Birch
Birch and aspen occupy about one-third of Minnesota's forest land. With a shortage of harvest-sized aspen over the next several decades, Minnesota scientists in the 1980s developed processes to incorporate birch into panel construction. Wood from aspen and birch has very different properties, but U of M research overcame those differences, showing how birch could be used to supplement aspen in oriented strandboard production. Today, that research is being used to fill some of the gap in the aspen supply.
University of Minnesota scientists in aquatic toxicology worked closely with the Environmental Protection Agency to examine the effects of various pollutants on fish and invertebrates. Through research in fish growth and reproduction, they helped shape the initial federal Clean Water Act regulation of hydrogen sulfide and cyanide. Today, researchers investigate more subtle effects of endocrine disrupting compounds on fish reproduction.
New Uses for Wood Residue
Researchers continue to investigate ways to use wood residue for products, yielding profits while reducing the amount heading to landfills. Wood waste can be shredded and used for animal bedding, composted to improve soil, chipped for mulch, or burned as fuel. But University wood product researchers have explored other uses of by-products since the beginnings of the paper industry in Minnesota.
Early studies of the chemistry of cellulose and lignin (a by-product of paper manufacturing) were made in the 1930s. It appeared impossible to make a functional plastic containing more than 25 to 40 percent lignin until 1998 when a U of M wood chemist created a material composed of 100% alkylated kraft lignin that is similar to polystyrene in tensile strength. Methods were devised to injection-mold the material into tough pieces. Creating plastic from lignin provides a profitable use for surplus kraft lignin that cannot be used in pulp mills. And properly formulated, lignin-based plastics are easily biodegraded by common fungi. Finally, wood is renewable, while petro-chemical plastics are not.
More recently, techniques developed by U of M scientists use waste wood, kraft lignins, and waste plastics to create a durable product that can be extruded for windows, doors, siding, and building materials for decks.
University marketing researchers worked with the world's largest window maker in the world, located in Minnesota, to track prospective customer contacts and develop a highly successful "Prospect Management Plan" for windows manufactured with the extrusion technology.
Fence Post Durability
In 1904, University researchers started testing the durability of treated and untreated fence posts—testing continued for more than 30 years. From a 1908–09 report: "About three thousand fence posts composed of basswood, cottonwood, willow, birch, hard maple, red oak, and ash have been treated with preservative . . . . The possibilities in the way of using our cheap woods . . . with preservatives will last as long or longer than our best cedar posts. If the farmers of our prairies can be shown how to treat these . . . it is an important matter." The findings found wide application throughout the wood products industry.