Copeland Creek Vegetation Management Project

students creating a pvc transectpvc stake in understory blackberriesstudent making vegetation height measurements

Project Description: The Sonoma County Water Agency, in collaboration with various partners, recently implemented a creek restoration project along Copeland Creek in Rohnert Park from Jasmine Court to Seed Farm Drive. The goal of the project is to manage vegetation along the stream bank in a manner that encourages beneficial species and controls undesirable ones, while also achieving flood-control objectives channel and banks. Techniques include removing non-native blackberry and increasing shade levels to promote colonization by natives, and limbing the lower branches of trees to allow maximum flow during floods.The project addresses 3 questions:

  • Does selective management of understory vegetation and trees result in increased creek shade and greater diversity of understory plant species over time?
  • What is the most effective way of controlling Himalayan blackberry regrowth using herbicides following creek and vegetation maintenance?
  • What are the impacts of different restoration treatments on the success of restoration plantings following vegetation management?

Duration: February 2012 - ongoing

Type of Educational Activities: Service-learning; professional work experiences

Project Faculty: Caroline Christian (Environmental Studies and Planning)

Partners: Sonoma County Water Agency

Participating Courses: Restoration Ecology (ENSP 423); restoration student blog;

Sampling Locations

The project area is stratified into 3 zones that correspond to ecological, hydrological and management differences. Points within each zone were randomly generated using a GIS. A portion of the points were selected for measurement according to specific criteria for inclusion. Permanent transects running perpendicular to the creek were established at each point.

water quality sampling locations on Copeland Creek

Elevation: At each transect, we recorded elevation using a range finder or similar device.

Herbaceous Layer: We measure herbaceous species richness and cover using point-intercept methods. We lay down a meter tape from that runs from the edge of the riparian canopy to the center of the creek channel (depending on flow levels). At set intervals, we record all species touching a pin flag placed perpendicularly to the meter tape. For a subset of the points, we record height of herbaceous vegetation. From the point-intercept data, we calculate species richness (number of species) and percent cover for native and non-native species.

Shrub Layer: We measure shrub species richness and cover using the line-intercept methods. For all shrubs intercepting the transect line, we record species and length of overlap. At set intervals we record shrub height. To calculate shrub cover, we divide the sum of overlap by total transect length. Species richness is calculated for native and non-native species.

Tree Layer: We measure tree species richness and cover on 4-meter wide belt-transects centered on the transect tape. We record all tree species occurring in a 2-m belt on either side of the tape. For each tree, we record species, diameter at breast height (dbh), and height. At set intervals along the center of the belt transect, we will record shade cover using a densiometer.

Photopoints: Photopoints are taken at a subset of transects.

Data Methods: Data are entered into an Access database and used to create an annual report with the following figures and tables:

  • Top 10 species by percent cover in each stratum (i.e. herbaceous, shrub, tree)
  • Richness, percent cover, and height of herbaceous species
  • Richness, percent cover, and height of shrub species
  • Richness, dbh, height and canopy cover for tree species
  • All vegetation data will be presented by plant grouping and origin
  • Pictures from photopoints

Additional Data (in development): We are pursuing additional measurements for:

  • Vertebrate richness and abundance surveys
  • Water quality measures/surrogates
  • Sediment characteristics and dynamics
  • In-stream habitat quality measures with focus on steelhead
  • Flora of Copeland Creek

Vegetation sampling is conducted by SSU students under the guidance of Dr. Caroline Christian.

Data: (see data disclaimer)

Presentations:

  • Riparian restoration of urban creeks. Caroline E. Christian, Dillon Lennebacker, Meghan J. Parish and Keenan Foster. 2013. Christian et al 2013 (pdf, 0.1 Mb).; 2013 WATERS abstracts. (Excerpt: initial data show a "negative relationship between canopy shade and shrub cover. 92% of shrub cover is Himalayan blackberry")

Reports:

Copeland Creek Restoration Project Monitoring Plan (2001). The report describes method to evaluate the effectiveness of SCWA's habitat restoration for a ~6,000 linear feet of Copeland Creek between Roberts/Pressley Road and Petaluma Hill Road (east of SSU campus). The project objectives were to ( 1) improve aquatic habitat and water quality through decreasing sediment, nutrient loads, and water temperature;( 2) decrease erosion through development of more stable channel banks and channel courses; and (3) increase fish and wildlife diversity and abundance. The plan provides information on how monitoring will be conducted and includes descriptions of stream cross-section profile, stream longitudinal profile, vegetation surveys, stream habitat and fish surveys, reptile and amphibian surveys, bird surveys, small mammal surveys.

University District Specific Plan Draft Environmental Impact Report; Chapter 3 Impact Analysis (January 29, 2010). The Draft EIR evaluates the potential for special status species in Copeland and Hinbaugh Creeks to be impacted by the proposed University District development. Field surveys are described on pages 3.4-4 to 26 and include methods, results, and a summary of all previous surveys (conducted 1994-2004) for special status plants, special status wildlife, special status fish, delineation of waters of the US (including wetlands), waters of the State, and biological communities. Fiffeen special status species (*Lobb’s aquatic buttercup,California tiger salamander, *foothill yellow-legged frog, *northwestern pond turtle, *Cooper’s hawk, *northern harrier, *white-tailed kite, *western burrowing owl, loggerhead shrike, California horned lark, *grasshopper sparrow, tricolored blackbird, *yellow warbler, yellowbreasted chat, *central California coast steelhead) were documented or have potential to occur in the study area. Documented species are indicated with asterisk (*).

Miller, S. 2000. The Birds of Sonoma State University. (no longer available at: http://www.sonoma.edu/projects/campus/birds/list.html)