Certified organic farmers are currently allowed to use conventional polyethylene mulch, provided it is removed from the field
at the end of the growing or harvest season. To some, such use represents a contradiction between the resource conservation
goals of sustainable, organic agriculture and the waste generated from the use of polyethylene mulch. One possible solution is to
use biodegradable plastic as mulch, which could present an alternative to polyethylene in reducing non-recyclable
waste and decreasing the environmental pollution associated with it.
Plastic mulch films in agriculture
Polyethylene plastic mulch is widely used for crop production worldwide, because it controls weeds, conserves soil moisture,
increases soil temperature, improves crop yield and quality, has a relatively low cost, and is readily available
BUT The high volume of waste generated by polyethylene mulches both in the field and in landfills raises many concerns (Figure 1)
Figure 1. (a) Typical post-season polyethylene plastic mulch waste in the field. (b) Ready for transport to the landfill.
Photo Credit: C. Miles, Washington State University. From Corbin et al.
Figure 2. (a) Starch-based biodegradable plastic mulch in experimental field plots during harvest, 135 days after laying mulch.
(b) 9 months post-harvest on soil surface, 348 days after laying mulch.
© 9 months post-incorporation, 348 days after laying mulch.
Photo Credits: J. Cowan (2a) and C. Miles (2a, 2b), Washington State University. From Corbin et al.,
Source articles.extension.org/pages/679 … on-systems