PROJECT ABSTRACT
Colorado Plateau Cooperative Ecosystem Studies Unit
(Cooperative Agreement # H1200-04-0002)
Park: Canyon de Chelly National Monument
Project Title: Developing Concepts for Stream Channel & Floodplain Restoration Phase
IV
Funding Amount: $96,724
CPCESU Partner Institution: Colorado State University
Principal Investigator : David J. Cooper, Ph.D., Department of Forest, Rangeland and
Watershed Stewardship, o. 970-491-5430, f. 970-491-6307, davidc@cnr.colostate.edu
Co-Investigator: Ellen Wohl, Ph.D., Department of Geosciences, College of Natural
Resources, Colorado State University, Fort Collins, Colorado, 80523, o. 970-491-5298, f.
970-491-6307, ellenw@warnercnr.colostate.edu
NPS Key Official: Scott Travis, Superintendent, Canyon de Chelly National Monument,
Chinle, Arizona, 80653, o. 928-674-5000, scott_travis@nps.gov
Start Date: July 15, 2007
End Date: May 30, 2009
Abstract:
Canyon de Chelly National Monument, Arizona has been invaded by two exotic riparian
plants, tamarisk and Russian olive, that are widespread in the southwestern United States.
The invasion of tamarisk and Russian olive has caused a loss of native riparian habitat, a
loss of historic views, and has occurred concurrently with substantial incision of the
stream channel in Canyon de Chelly and Canyon del Muerto. Stream bed incision in the
canyons has caused a drop in water table which prevents traditional farming practices of
the Navajo people. This project was initiated to study the ecological and geomorphic
processes involved with tamarisk and Russian olive invasion into the canyon as well as
the response of the stream channel and riparian plant community to tamarisk and Russian
olive removal. This study was initiated in the summer of 2005, at which time pretreatment data was collected in six study sites in Canyon de Chelly. Removal of tamarisk
and Russian olive was conducted in the study sites from fall of 2005 through fall of 2006.
During the summers of 2006 and 2007, post-treatment data was collected pertaining to
the geomorphic response of the channel, the response of ground water, aerial seed rain,
nitrogen availability and plant community composition. As well, the topography of
associated alluvial terraces was reported relative to the elevation of the current stream
channel. Geomorphic field data will be used in a bank stability modeling effort to predict
longer term (more than 50 years) channel adjustment to plant removal at one of the study
sites, which serves as a detailed case study. Additional information is being collected on
the ages of tamarisk and Russian olive plants throughout the canyons to understand the
timing of invasion. Lastly, data is being collected to quantify the seedling establishment
requirements of tamarisk, Russian olive and the native cottonwood tree in a controlled
experiment as well as in the field. During fall of 2007, data will be collected to quantify
seedling establishment in the field and more samples will be collected for aging of
tamarisk and Russian olive. The final surveys of the study site serving as a case study
will occur in fall 2007. During winter and spring of 2008 these data will be analyzed and
the results supplied to CACH in a final report, which will include one completed
dissertation (K. Yaeger), completed chapters of a second dissertation (L. Reynolds), and a
completed master’s thesis (D. Cadol). The report would include an introduction to the
entire project, and an overall project summary and synthesis.
Keywords: Exotic plants, geomorphology, channel change, vegetation treatments,
vegetation change.