Strawberry Creek Planting - Filling the Weed-Shaped Hole

Project Leads: Lauren Hallett, Nathan Bickart, Lawrence Fernandez, Dr. Katharine Suding

Sponsor: Suding Lab

TGIF Grant: $16,232

Project Theme: Habitat Restoration

Project Location

2012 Application Submission

Application Metrics

Status: Complete

Historial Context: Over the past 25 years, the Strawberry Creek Restoration Program (SCRP) has engaged thousands of UC Berkeley students and volunteers in the restoration of Strawberry Creek restoration, which has resulted in large areas where some of the most problematic invasive species (notably English and Algerian ivy) have been removed. In more recent years, the SCRP has begun to shift its focus from invasive species removal to a more comprehensive restoration approach that includes native planting. Removing invasive species without effectively establishing other desired (native) species can leave a "weed-shaped hole" that invasive species can easily recolonize. Ideally, native planting fills this "hole" with a community that supports a higher level of biodiversity.

Project Description: This grant will fund five student internships and the supplies needed for identifying and planting native species that can resist re-invasion by ivy and still realize the other essential ecosystem services desired by the campus community.

Goals: Utilize information on species traits to optimize the sustainability outcomes of the native planting phase of the Strawberry Creek restoration. Measure traits (such as relative growth rate, height and root morphology) on these native species and contrast them to the traits of ivy. Consider traits related to the effects the species has on habitat (e.g. height, branching patterns) and water quality (e.g. root depth). Increase on-campus field experiences for students by leading class tours of restoration areas. Extend our trait-based restoration framework to other community watershed groups. Shift from invasive species removal to native species planting and address difficult questions about species selection through collaboration between ecologists and the Strawberry Creek Restoration Program. Grow selected species in the nursery, and lead volunteer efforts to plant these species along the creek in a replicated experimental layout. Monitor the establishment success of planted species and the spread of ivy in planted and non-planted areas. Report the findings in a handbook of planting recommendations.

TGIF Blog Posts about Strawberry Creek

2013 Poster

Project Timeline

Summer 2012 Grew over 2000 native plants of 60 different species.
Fall 2012 Measured functional traits on 40 of these species and on invasive species found along the creek.
Organized volunteer events with the SCRP to prepare planting sites for the winter/spring planting season. Activities at these events included ivy removal and sheet mulching (placing cardboard and mulch above the soil to prevent re-invasion of the site).
Winter 2012 Analyzed the data from the functional trait measurements using Principal Component Analysis, and designed planting recommendations to achieve project goals.
Spring 2012 Implemented native plantings during volunteer-driven events.
Monitored the sites for plant survival and reinvasion by non-native species.
Coordinated with a new generation of SCRP leaders to share information and help design new TGIF-sponsored projects along the creek.

2012-2013 Accomplishments

  • Synthesized existing Strawberry Creek restoration documents; Compile species lists from previous projects and regional lists.
    • Reviewed all available documents of what has previously been planted along the creek. The project team met with Jim Horner (Capital Projects) and Tim Pine (EH&S) to discuss the creek's history and choose different species mixes for planting. The team obtained a regional species list from Urban Creeks Council and hired another research assistant to write a report synthesizing previous work along the creek.
  • Conducted a literature review to determine traits to measure.
    • Measured specific leaf area, stomatal conductance, leaf chlorophyll levels, height, seed mass, rooting depth and morphology and, on a subset of species, nitrogen uptake rates. This information will assist with targeting plantings on species that are likely to be successful.
  • Grew target species in the nursery.
    • The project team has 5 replicates of 50 different species to measure, as well as a stock of plants to out-plant along the creek. Information from measuring the replicate plants will assist in targeting restoration efforts and the rest of the plants will be outplanted along the creek.
  • Measured traits on nursery-grown plants.
    • The team completed the non-destructive measurements (stomatal conductance, chorophyll, seed mass and height) and destructively harvested plants for the remaining measurements in mid-October.
    • All trait measurements were completed with a team of URAP students, honors thesis students, and community volunteers. 
    • The project team analyzed the data to identify species with similar traits to ivy and designed a planting palette with those species.
  • Hired two undergraduates to grow target species and measure traits.
    • Nathan and Lawrence were essential players in acquiring and measuring all plants, and they used their experiences from summer 2012 to develop their own research projects along the creek (which were both funded by SPUR). Nathan and Lawrence were highly motivated and their efforts increased the number of plants for outplanting along the creek. They also led volunteer groups that helped cultivate plants in the nursery.
  • Hired a graduate student to supervise students and aid in nursery work.
    • Lauren worked with Nathan and Lawrence in the nursery, helped to trouble-shoot issues as they arose, and taught (and helped conduct) the trait measurement techniques. Lauren helped ensure this project stayed on track for outplanting along the creek and engaging more undergraduates in environmental stewardship. 
  • Analyzed Data
    • Lauren cleaned and processed the data, and the team analyzed the data and selected different planting palettes. The team enlisted the help of the volunteers who had assisted with the trait screening.
  • Hosted 2 volunteer days to help outplant 4 different sites of native species similar to ivy along Strawberry Creek during January and February 2013.
  • Nathan presented the project's work to the Advisory Board for the College of Natural Resources and at the 2013 CACS Sustainability Summit.
  • Dr. Suding shared the project's work in guest lectures to several on-campus ecology classes and at the 2012 Society for Conservation Biology meeting held in Oakland, CA.
  • Lauren will present the project's work at the 2013 National Conference on Ecological Restoration in Chicago, IL and at the 2013 Society for Ecological Restoration Conference in Madison, WI.

  • Engaged over 250 student and community volunteers in urban creek restoration, through coordination with the Strawberry Creek Restoration Program (SCRP). These volunteers served over 450 volunteer-hours over the course of 11 educational volunteer events.
  • Removed ivy (and other invasives) from and sheet mulched over 100 m2 of riparian habitat along Strawberry Creek.
  • Propagated approximately 2000 individuals of 60 native plant species in the Strawberry Creek Native Plant Nursery.
  • Planted 348 native plants in four focal areas along Strawberry Creek, and approximately 500 plants in other sites along the creek.
    • The project team selected species based on the trait-screening results, which suggested they would likely resist re-invasion by ivy and therefore be sustainable.
  • Maintained a written record of this work, which has been shared with new leaders of the SCRP and may be published in Restoration Ecology

Project Photos

Final Report

The Suding Lab and the SCRP will remain active on this project, continuing to work Dylan Chapple, a Suding Lab member, on the 2013 TGIF Grant Fitting Plant to Place: Site-Specific Restoration on Strawberry Creek. They will focus on designing new efforts that utilize this project's data and outplantings. Dylan has already recruited two CNR undergraduates for this work and will also liaison with a local high school to extend the project's outreach efforts.

Mission Statement

The Green Initiative Fund (TGIF) provides funding for projects that reduce UC Berkeley's negative impact on the environment and make UC Berkeley more sustainable. TGIF will allocate funds to projects that promote sustainable modes of transportation, increase energy and water efficiency, restore habitat, promote environmental and food justice, and reduce the amount of waste created by UC Berkeley. Portions of the fund also support education and behavior change initiatives, student aid (via return to aid), and internships. TGIF is supported by student fees and administered through a student-majority committee and a program coordinator.