An Assessment and Management Protocol for
Arundo donax in the Salinas Valley Watershed
by Alana J. OakinsMay 2001
What is Arundo?
• invasive non-native species
• introduced in the 1800’s• rated 1 of 5 top species
of concern by CALEPPC• many associated
environmental problems
Why Should We Care?• out-competes
native vegetation• inability to
provide habitat and food for native species
• negatively affects stream flow and morphology
• water intensive
What can we do?
• federal, state and local “weed” laws (e.g. Clinton’s Executive Order and SB1740 & AB1168)
• economic and ethical implications to different stakeholders like landowners, agricultural community, and nurseries
• research (e.g. mapping studies)
Study Objectives
• to assess the feasibility of mapping Arundo using remote sensing
• to offer a policy recommendation for Monterey County
Assessing Arundo using Remote Sensing
• Why map Arundo?-it’s the first step-locating made easier-assess quantity-assess invasiveness-gives future direction
• Therefore…Can Arundo be differentiated from similar vegetation?
Study Site
• near Gonzales, CA
Methods• Acquired imagery…Color-IR• Groundtruthed the image • Created training classes • Trained computer in TnTmips
(MicroImages, 1999) • Supervised classification
ResultsTraining Class Statistics
35
50
65
80
95
110
125
140
Infrared Red Green
Band
Mean Arundo
Willow
-Arundo is significantly different than similar vegetation
• Mapped Arundo with an accuracy of 95%
LegendGreen-ArundoRed-WillowPink-CottonwoodPurple-OakYellow-Grasses and ShrubsWhite-Bare GroundDark Blue-Water (deep)Light Blue-Water (shallow)*Black polygons-groundtruth data and training classes
Discussion
• use a Color-IR • nominal pixel size of 2 m• supervised classification• red and green light
reflectance bands
A proposed policy…
• Arundo be included in the Monterey County Weed Management Plan
• funds be allocated for further Arundo research (e.g. mapping entire infestation)
An Effective policy...
• completely understand why Arundo even exists in Monterey County
• look to successful management examples as a guide
• public and private collaboration
Acknowledgements
• Scott Hennessy• The Watershed Institute• Dr. Lars Pierce• Dr. David Takacs• Lee Johnson• Bruce Delgado
