Closing the Loop: Sustainable Material Use of Cardboard to Address Dwindling Market.

Packaging, especially cardboard, is part of our daily lives on a college campus where virtually everything comes in boxes, thereby creating a vast volume of waste. Iowa State University (ISU), with over 33,000 students as well as about 6,000 faculty and staff, generates, on average, 70 tons of cardboard boxes every month. A few years ago, baled cardboard was most in-demand, which made it a "commodity" that generated revenue but not anymore due to the challenging US recycling market impacted by China's "National Sword" policies. Communities across the US, including higher education institutions like ISU, have been affected by the disruptions in the recycling markets, which has led to increased costs, putting strains on funds. As a result, many communities and institutions have stopped recycling these materials and are sending them to landfills, which is a cause for concern. As a leader in advancing sustainability initiatives, ISU explored alternative solutions to cardboard recycling by using campus-generated cardboard boxes for animal bedding and compost. ISU's animal farms use corn stovers for animal beddings. Two different commercial methods (grinding and shredding) were used to breakdown boxes to determine the best bedding material type for cattle. The shredding method produced a baleable kind of cardboard that were quickly processed, which were applied as beddings for two months, and compared with corn stovers to determine its effectiveness. We experimented with eight animal pens on the same schedule placing four with shredded cardboard and the other four with corn stovers. Four pens were stocked light (i.e., four animals per pen), and another four pens were stocked heavy (i.e., seven animals per pen). Cattle were bedded twice weekly for four weeks, and the pens cleaned out after two weeks with pictures were taken regularly to compare results as well as the behavior of the animals. Results indicate that the pens with shredded cardboard remained dry after four days, the cows were clean, and the feed intake was consistent. It had a better absorbent characteristic, and the cattle appeared comfortable on the cardboard bedding than on the corn stover. Other observed benefits include it's environmental, and health-friendliness for the cattle, which eliminates dust and potential molds, and the cattle had no tendencies of eating them. On the other hand, pens with corn stovers showed poor absorbent properties after four days, making the cattle dirty, uncomfortable, and food intakes inconsistent. Also, pens with corn stovers produced dust, and animal consumption of corn stovers affected animal research. The shredded cardboard bedding was composted for soil amendment, thereby increasing soil nutrients. A manure analysis was conducted for both cardboard and corn stover bed materials, and it revealed that cardboard-composted bedding was denser than corn stover and the processed cardboard beds composted much faster than corn stovers. However, composted corn stovers had higher nutrient values than cardboard compost with conclusions made based only on the soil requirements of the farm. This characterization may not apply to other farmlands with different soil requirements. [ABSTRACT FROM AUTHOR]