Filling the weed-shaped hole: Determining an
effective planting palette for Strawberry Creek Lauren Hallett, Nathan Bickart, Lawrence Fernandez and Katharine Suding
Department of Environmental Science, Policy & Management, UC Berkeley
Every year over 500 undergraduates care for Strawberry Creek by pulling the invasive ivy that
blankets its banks. Without planting new species, this may create a “weed-shaped” hole that ivy
can refill. Our goal was to select and plant species that limit ivy re-invasion.
What we did: Species with similar traits to ivy – such as similar growth rates and shade tolerance – should
be more competitive. We measured the traits of 40 species to identify plants that can compete with ivy.
Roots Shoots Specific leaf area: Thick leaves
last longer and are more drought
tolerant
Chlorophyll: Higher leaf
chlorophyll content increases
photosynthesis rates and growth
Conductance: Low conductance
means less water is lost during
respiration
Height: Greater height is
associated with faster growth
Specific root length
& Proportion of fine
roots : Thin roots
have more surface
area but are more
fragile
Rooting depth: Deep
tap roots increase
drought avoidance
Root:shoot ratio: Higher root to shoot ratios
decrease susceptibility to drought
Species that clustered near ivy in multivariate
trait-space are functionally similar to ivy. We grew these functionally-
similar species in the
Strawberry Creek nursery.
And then planted them along Strawberry Creek.
800 plants With the help of 250 volunteers
We will keep an eye on these plants over the next year to assess how successfully they compete with ivy.
Thanks to: Jesse Fried and Martin Alexander for long hours measuring traits, Tim Pine and the Strawberry
Creek Restoration Program for guidance and planting support and Katherine Walsh for logistical help.
Ivy
Ivy