March 24, 2010
Biodegradable Mulch: Applying Textile Science for a Positive
Impact on Agriculture
New research in the WSU Apparel, Merchandising, Design and
Textiles Department is proving there is a lot more to AMDT than
sewing and pattern making.
Scientists in AMDT are involved in a research project to develop
a biodegradable mulch that would provide an alternative to costly
and environmentally detrimental plastic mulch.
The research project spans three states and five research
institutions, said Debra Inglis, associate plant pathologist and
project director. Inglis is based at WSU’s Northwestern
Washington Research and Extension Center in Mount Vernon.
“Not only does this project span different disciplines,
departments and universities, but it also spans across different
research centers. The fact that we in Pullman can collaborate
with the center in Mount Vernon is quite unique,” said Karen
Leonas, chair of the AMDT department.
The textiles department is playing a significant role in the
research. The Textile Research Lab is responsible for testing many
of the intrinsic qualities of both fabric and plastic mulches, Leonas
said. Two AMDT undergraduates, Marc LaPointe and Leanne
Goldstein, are conducting the physical and mechanical testing of
the mulches……
Vegetables being grown under
plastic mulch. WSU researchers
are investigating a biodegradable
alternative using textile science.
For more information on the
biodegradable mulch project,
please visit
http://bit.ly/b6AGI3.
The SCRI Grant
Biodegradable Mulches for Specialty Crops
Produced under Protective Covers….
What it is and how we got there,
… the role of AMDT
I.
II.
III.
Background
Planning Project Grant
SCRI SERP Grant
a. Experimental design
b. Testing in AMDT
Terms
SCRI – Specialty Crops Research Initative
 RFA – Request for application
 CAPS – Coordinated Agricultural Projects
 SERP – Standard Research & Extension Projects
 Protective Crop Covering Systems – High tunnels,
low tunnels, mulches
 Specialty crops – fruits, vegetables, tree nuts, dried
fruits, horticulture and nursery crops
 Trans-disciplinary - a multi-discipline approach
bringing biological & physical scientists together with
economists & social scientists to address challenges in a
holistic manner.
 PLA – Polylactic Acid
 Polyethylene – plastic mulch
 BDM – Biodegradable Mulches

Executive Summary from SCRI RFA

“The National Institute of Food and Agriculture
requests applications for the SCRI to solve critical
United States specialty crop issues, priorities, or
problems through the integration of research and
extension activities that take systems-based, transdisciplinary approaches. The intent of the SCRI is to
solve the needs of the various specialty crop industries
through the promotion of collaboration, open
communication, the exchange of information and the
development of resources that accelerate application
of scientific discovery and technology. “
Systems Approach
“The philosophy of the SCRI is that truly effective, long-term solutions to
specialty crop industry problems can best be achieved by understanding
and treating those problems as complex systems of many interacting
components.”
Karen & Larry discuss
degradable mulches
Karen
contacts
Larry
SCRI RFA
Announced
Karen contacts
Rick Knowles,
HLA
Larry makes contacts
with Tennessee & Industry
Rick contacts Carol Miles
who contacts Debbie Inglis
Debbie & Carol contact Karen,
industry representatives, and
researchers at other instiutions
Discuss SCRI grant options,
prepare planning grant
Receive planning grant -hold
meeting
Prepare , submit, receive
SCRI SERP grant
Planning Grant
SCRI PROJECT PLANNING MEETING: CSREES AWARD NO. 2008-511800488
PLANNING FOR SPECIALTY CROP COVERS THAT USE
DEGRADABLE MATERIALS
October 30 – November 1, 2008, University of Wisconsin, River Falls
Received Award letter October 3, 2008
Amount Received: $98,181
 “Washington,Tennessee and Texas scientists in materials and
textiles, economics, horticulture, plant pathology and soil
microbiology propose a SCRI R&E Planning Project, “Protected
Specialty Crop Covers that Use Degradable Materials” to better
integrate the crop protective covers and degradable materials
subject areas for the benefit of specialty crop production.”
Meeting Expectations & Project Outcomes

Working CAPs proposal outline, with prioritized objectives, and general research/outreach
plans and budget and personnel requirements

New professional acquaintances, and personal interaction with team members and
stakeholders

Introduction to key national leaders in the fields of interest

Perspectives of stakeholders, and their prioritization of research and outreach issues

Protocols and methodologies outlined for collaborative studies, outreach, and project
evaluation—all with scheduled times of completion for inclusion in a timeline for the CAPs

Subsequent dialogue with regional stakeholders via a Key Informant Survey in order to insure
continued stakeholder input into CAPs proposal development

Identification of budget and personnel needs

New information to share with local audiences upon participants’ return home via local and
regional meetings, Extension newsletters, and web pages.

Identification of potential pitfalls

Greater familiarity and expertise among team members on federal grants writing process

Cross-disciplinary training and education among team members including i) creation of a
glossary of shared terms, ii) crop production specifications for materials and fabric scientists,
and iii) materials and fabric capabilities information synthesized for crop production scientists.

Planning project evaluation instrument completed

Development of a successful CAPs proposal!
SCRI Planning Meeting Working Groups
Crop Production

Annette Wszelaki, Working Group Chair -Dept of Plant Sciences - Extension , University of Tennessee

Debra Ann Inglis , Dept. of Plant Pathology, Washington State University NWREC
Carol Miles , Dept. of Horticulture and Landscape Architecture ,Washington State University NWREC

Hector Saez , Center for Sustaining Ag and Natural Resources, Washington State University NWREC

Tom Walters ,Dept of Horticulture and Landscape Architecture ,Washington State University NWREC

Andrew Corbin , WSU Snohomish County Extension

Curt Beus , WSU Clallam County Extension

Marion Brodhagen , Dept of Biology, Western Washington University

George (Ben) Craft, Alm Hill Gardens , Everson, WA 98247

Allison and Paul Wiediger, Au Naturel Farm, KY

Tom Thornton , Cloud Mountain Farm , Everson, WA 98257

Edward (Ted) Ewing Carey Department of Horticulture, Kansas State University

Bill Lamont, Department of Horticulture, Pennsylvania State University

John Biernbaum , Department Plant and Soil Sciences, Michigan State University

Russell Wallace, Department of Horticulture Sciences & Extension, Texas A & M University

Roy Riddle ,Carolyn Lanier Youth Farm, Texas
Indicates Industry Partner
Materials/Technology

Karen K. Leonas, Working Group Chair, Apparel, Merchandising, Design & Textiles, WSU

Douglas Hayes, Dept. of Biosystems Engineering and Soil Science , University of Tennessee

John Dorgan , Site Director, Dept. of Chemical Engineering, Colorado School of Mines

Hang Liu, Dept. of Apparel, Merchandizing, Design & Textiles, WSU

Ramani Narayan ,Dept. of Chemical Engineering and Materials Science, Michigan State
University

Rita Schenck ,Institute for Environmental Research and Education,Vashon WA

Robert Green , Natureworks LLC , Carey NC

Tim Chaput , J&M Industries Inc.

In attendance
◦ 24 stakeholders participated
◦ 8 universities
◦ 6 industry partners
◦ 10 disciplines
◦ 9 states
Indicates Industry Partner
Preparation of Proposal for 2009 SCRI RAF
Utilized information from Planning Meeting
 Gained input from
◦ Grower advisors Industry representatives
◦ Scientific experts
 Organized Key Informant Survey
 Developed four groups

◦ Crops

Materials

Socio-economic

Soils
Proposal focused on two SCRI Focus Areas
 Improve long-term production efficiency,
productivity, profitability
 Identify and address threats from pests/diseases).
SCRI SERP Grant
BIODEGRADABLE MULCHES FOR SPECIALTY CROPS
PRODUCED UNDER PROTECTIVE COVERS
October 31, 2009 – October 30, 2012
Amount Received: $199,900
“…will help to ascertain whether leading commerciallyavailable and experimental spun-melt nonwoven BDMs
provide services of similar quality to conventional plastic
products, are commercially viable, have potential for
sustainable high tunnel environments, are better for the
environment, and if nonwovens (which can be readily
manufactured) have sufficient attributes to serve as
prototypes for the next generation of BDMs.”
The long-term research and outreach goals of this SREP
proposal
1.
2.
3.
4.
5.
contribute to the protective crop cover knowledge base by
testing existing and emerging BDM materials which can augment
the polyethylene plastics now dominantly used for mulches in
specialty crop systems,
develop management strategies for using mulches on key crops
in high tunnel systems that mitigate against inclement weather
(high winds, heavy rains, high humidity) and pest/disease threats,
and in so doing lead to
the adaptation, environmental sustainability and economic
feasibility of BDMs in high tunnel systems for the PNW (cool
marine climate), M-S (hot, dry climate) and SE (hot, humid
climate), regions currently underserved by University research
and education programs, and then, with entry of the three
regions into this arena,
gain a better understanding of mulch biodegradation and the
potential effects on soil ecology and root health, which will help
to
promote research and development on BDMs in the future.
SCRI TEAM on SERB Project
Project Director, Debra Ann Inglis, Department of Plant Pathology, WSU NWREC









Eric Belasco, Economist,Texas Tech
University
Curt Beus, Sociologist and
WSU/Clallam Co. Extension
Marion Brodhagen, Cellular &
Molecular Biologist, Western
Washington University
Andrew Corbin, Ecologist and
WSU/Snohomish Co. Extension
Ana Espinola-Arredondo, Economist,
WSU Pullman
Suzette Galinato, Economist, WSU
Pullman
Doug Hayes, Biosystems Engineer,
University of Tennessee-Knoxville
Robert Jones, Sociologist, Energy,
Environment and Resources Center,
University of Tennessee-Knoxville
Jaehoon Lee, Environmental and Soil
Physicist, University of TennesseeKnoxville










Karen Leonas,Textile Scientist,WSU
Pullman
Hang Liu, Post-doc and Textile
Scientist, WSU Pullman
Tom Marsh, Economist, WSU
Pullman
Carol Miles,Vegetable Horticulturist,
WSU NWREC
Jennifer Moore-Kucera, Soil and
Environmental Microbiologist,Texas
Tech University
Srinivasa Ponnaluru, Economist,
WSU Pullman
Larry Wadsworth, Nonwoven
Textiles Scientist, University of
Tennessee-Knoxville
Russ Wallace, Horticulturist,Texas
Agri-Life REC
Tom Waters, Small Fruit
Horticulturist, WSU NWREC
Annette Wszelaki, Horticulturist,
University of Tennessee-Knoxville
Protective Covers

Types:
◦ High Tunnels, Low Tunnels, Mulches

Purpose:
◦ Extend growing season

Mulches also
◦
◦
◦
◦
◦
◦
Moderate soil temperatures
Reduce moisture loss from soil
Reduce weed growth
Disease protection
Reduce soil loss
One-year use
Mulches

Currently
◦
◦
◦
◦

Most available are plastic (polyethylene)
Price is increasing as are petroleum based
Do not degrade and cannot be composted
Upon loss of integrity – fragment increasing labor to
remove from plots
Mulch selection
◦ Consider laying equipment – strength, flexibility*
◦ Cost
◦ Color

Mulch characteristics to consider
◦ Chemical Composition
◦ Physical structure
Biodegradable Mulches (BDM)

Biodegradable – process by which microorganisms
convert material into biomass, CO2 & H2O

Degradable – process where very large molecules are
broken into smaller molecules or fragments

Degradable polymeric material – designed to undergo
a significant change in chemical structure under
specific environmental conditions resulting in loss of
properties
Previous BDM’s commercially available
Photodegradable
 Paper based

Experimental Design for Materials Group
6 mulches x 4 times x 3 locations x 2 environments x 4 reps

6 Mulches
◦ Biobag
BioTelo Meltblown PLA
◦ Non-biodegradable Cellulosic Mulch



Spunbond PLA


Times
◦ Control

First flower

Final harvest

Locations
◦ WA

Field control


TN

TX
Environments
◦ Inside Tunnel

Outside tunnel
Experimental Design for Materials Group
6 mulches x 4 times x 3 locations x 2 environments x 4 reps

6 Mulches
◦ Biobag
BioTelo Meltblown PLA
◦ Non-biodegradable Cellulosic Mulch



Spunbond PLA


Times
◦ Control

First flower

Final harvest

Locations
◦ WA

Field control


TN

TX
Environments
◦ Inside Tunnel

Outside tunnel
Mulches

Mulch characteristics to consider
◦ Chemical Composition
◦ Physical structure
◦
◦
◦
◦
In this study – 6 mulches
Biobag
BioTelo
Meltblown PLA
Spunbond PLA
Non-biodegradable Cellulosic
Marketed as Biodegradable



Mulch Chemical Structure
PLA
Cellulose
Polyethylene (nonbiodegradable)
Corn Starch (BioBag,
BioTelo)
(C6H10O5)n
Mulch Physical Structure
Cellulose
Meltblown PLA
Spunbonded PLA
Comparison of Meltblown & Spunbond
250 nanometer average diameter meltblown on 20 micron diameter spunbond
http://www.hillsinc.net/nanomeltblownfabric.shtml
26
Experimental Design for Materials Group
6 mulches x 4 times x 3 locations x 2 environments x 4 reps

6 Mulches
◦ Biobag
BioTelo Meltblown PLA
◦ Non-biodegradable Cellulosic Mulch



Spunbond PLA


Times
◦ Control

First flower

Final harvest

Locations
◦ WA

Field control


TN

TX
Environments
◦ Inside Tunnel

Outside tunnel
Location & Environment

Locations
◦ Pacific Northwest - cool marine climate
◦ Mid-South - hot, dry climate
◦ Southeast - hot, humid

Environments
In tunnel
Out of tunnel
Textile Research Laboratory Testing
Mechanical properties, such as flexibility and durability, are critical for mulches to be
successfully laid onto beds with commercial agricultural bed shaper/mulch layers,
and to remain intact and withstand wind through the entire growing season. Pore
size and its distribution are important parameters indicating air and water vapor
permeability of fabrics










thickness (ASTM D1777-96(2007)),
weight (ASTM D3776-09),
flexibility (IST 90.2 (01)),
durability [tensile and elongation (ASTM D5035-06(2008)e1)],
tear strength (ASTM D5734-95(2001)), and
abrasion resistance (ASTM D4966-98 (2007)], deleted from
study 1/10
pore size and distribution (Epps et al., 1997),
light transmission
accelerated weathering
SEM micrographs
Changes in mechanical properties
indicate degradations:
•Reduction
in elongation indicate reduction in
amorphous regions – usually first attacked in deg.
process
•As polymer chains are broken, reduction in dp - lower
tenacity
•Crystalinity is related to tear strength
•Increase in pore size indicates increases opening sizes
which could be result of degradation – loss of integrity
•Reduction in weight indicates reduced MW – sign of
degradation
Thickness
tester
Stiffness
Strength/Elongation
Porometer
Die Press for cutting
Tear Tester
Weatherometer
Materials Group WSU Research Team
Karen K. Leonas – Co Project Director
Dr. Hang Liu,
AMDT Post Doctoral Researcher
Key Project Investigator
AMDT Undergraduate Students
Jeremy Cowan,
Horticulture &
Landscape Arch
PhD student
Leanne Goldstein
Marc Lapointe
Project Timeline
from Fall 2007 - Present
SCRI RFA is
released Karen
contacts Rick
Knowles, HLA
Recieve
grant &
Plannning
meeting
held
Falll 2007 Win 2008 Spr 2008 Sum 2008 Fall 08
Larry Wasdsworth
& Karen discuss
meltblown mulch
product
Recieve
notification
of award &
begin
obtaining
materials
Carol & Debbie
express interest,
prepare
planning grant
Win 09
Spr 09
Sum 09
Prepare &
submit SCRI
SERB grant
Begin material
tesing & field
planting
Fall 09
Win 10
Spr 10
Recieving
materials/
equipment training
Sum 10
Thank You!
Questions?