Coated with Vegetable Oil Offers Biodegradable Alternative to Plastic
By Linda McGraw
March 12, 2001
Paper is gaining over plastic in
mulches used to grow commercial fruits and vegetables as well as the home-grown
varieties, according to Agricultural
Research Service (ARS) studies in Peoria, Ill. A main reason for this trend
is that vegetable-oil-coated paper mulch may be a less costly alternative to
plastic mulches, which are expensive to remove.
Brown paper coated with vegetable oils like soybean and linseed oil can
protect the crop from weeds and insects and is completely biodegradable,
according to ARS chemist Randal L. Shogren at the
National Center for Agricultural
Utilization Research (NCAUR) in Peoria, Ill. That gives paper a big
advantage over plastic mulches that cost about $240 an acre. Soy oil costs
around 15 cents a pound, so growers and home gardeners can expect a reasonable
cost for paper mulches made with vegetable oil.
Shogren coated plain brown kraft paper--used to make grocery store
bags--with several types of vegetable oils, including soybean, linseed and a
chemically-modified soybean oil plus a catalyst. The vegetable-oil-coated paper
withstood wind and rain long enough for the crop to grow, but then began
degrading in the soil.
In trials, Shogren found that kraft paper treated with a combination of
epoxidized soybean oil and citric acid held up for 13 weeks compared to
untreated kraft paper, which was 50 percent degraded in 2-1/2 weeks. A U.S.
patent on the technology has been approved. Field trials in Live Oak, Fla., in
cooperation with the University of Florida
(Gainesville) are in progress. Currently, field trials are being planned with
an industry partner.
Shogren presented information on the paper mulches at the 6th International
Conference on Frontiers of Polymers and Advanced Materials in Recife, Brazil,
ARS is the chief scientific research agency of the
U.S. Department of Agriculture.
Scientific contact: Randal L. Shogren, ARS National Center for
Agricultural Utilization Research, Peoria, Ill., phone (309) 681-6354, fax
(309) 681-6691, firstname.lastname@example.org.