There once was a great future in plastics, but their waste is weighing that future down. Scraps and bit cumulatively reaching more than 250,000 tons end up in the ocean, and even the smallest particles cause trouble as they clog corals. Eventually some of the six billion tons of plastic manufactured since the mid-20th century becomes a sort of stone, an aggregate of bound plastic and rocks.
Scientists still aren’t sure how so much plastic ends up in the ocean, but they do know where much of it starts. Elizabeth Grossman visited a small farm owned by Kara Gilbert to track down agricultural plastics. She reports for Ensia:
On a visit to the four-acre farm on lush Sauvie Island at the confluence of the Willamette and Columbia Rivers near Portland, Ore., Gilbert gives me a tour de farm plastics. The fields are just being readied for the season, but black plastic is already laid out under a hoop house. PVC water pipes are being set into place and drip irrigation tape is ready to be deployed, as are plastic sacks of fertilizer. Out in the greening field, little orange-pink plastic plant tags on ankle-high stakes flap in the wet breeze to mark rows of just-sprouted peas.
This tiny produce farm buys between $4,000 and $6,000 worth of plastic every year, Grossman writes. Multiply that number times the number of farms and keep in mind that the larger farms will use much more… you get the picture. Bales are wrapped, greenhouses covered, pesticides stored all in plastic. Gene Jones of the Southern Waste Information eXchange estimates that the U.S. uses about one billion pounds of plastic in agriculture every year.
Fortunately, we are trying to do better. Farm plastics are no longer burned or buried on farm property, or at least most states ban the practice. Now growers are trying to use less plastic by reusing when they can. Grossman writes:
By far the biggest opportunity to reduce farm plastic waste, however, is through recycling. Currently only about 10 percent of farm plastics are recycled. Increasing that number will depend on making drop-off more convenient and expanding options for giving plastic a second life.
In New York, where a statewide ban on backyard or farm burning of plastics was passed in 2009, the Cornell program worked with the state’s Department of Environmental Conservation to pioneer agricultural plastics recycling and do educational outreach about recycling options through extension programs and local soil and water conservation districts.
But recycling farm plastic can be challenging. Grossman spoke to an Oregon-based company that recycles baling twine, the orange plastic rope that keeps hay bales together. Apparently the material is so abrasive that many machines can’t handle it. Workers have to remove the pieces of hay still clinging to the twine painstakingly by hand. Another company makes reusable grocery bags from ag plastics. A third processes old irrigation pipes into pellets that can be used to make plastic sheets and films for growing produce.
The use of biodegradable plastics might also help — a Washington State University publication cites the benefits of plant starch-based mulches, as opposed to petroleum-based plastic mulches, used for weed suppression and to keep soil warm and moist for growing crops.
Like many multifaceted issues, the problems posed by ag plastics won’t have one solution. Hopefully we can have many creative solutions, such as the Netherlands’ plan to nab plastic before it escapes to sea and build floating parks for humans above and fish and sea creatures below.