to eradicate.UC Davis Natural Reserve System - McLaughlin Reserve
The California Department of Fish and Game (DFG) and the
University of California Davis (UCD) are working on eradicating tamarisk (salt
cedar, Tamarix sp.) and
other invasive non-native plants from the
upper Putah Creek watershed along the Knoxville and Eticuera Creeks and actively
restoring native vegetation. Tamarisk
is a highly invasive shrub/tree that spreads rapidly, alters the water table and
soil nutrients, excludes native species, and provides a poor food source for
native birds, insects, and rodents. Perennial pepperweed (Lepidium latifolium)
and tree of heaven (Ailanthus altissima) are additional invasive species that this project
looks to eradicate.
Efforts to restore the riparian corridor to a more diverse native habitat began
as soon as DFG took ownership of the Knoxville Ranch.
The first step was the removal of cattle in the
riparian areas. The removal of grazing allows trees and plants to establish and
grow. The next step is to eradicate the highly invasive non-native
plants and trees that out-compete the natives. After the removal of the exotics, some areas will be planted with native plants, shrubs, and trees
to foster their re-vegetation. Other areas less impacted by present invasive
species will be left untouched and allowed to regenerate naturally. The final
step is to monitor conditions, remove any re-growth of non-natives, and continue
plantings of natives where appropriate.
Cutting the plants and treating the cut stems with an
application of herbicide will remove the bulk of the
tamarisk. The California
Department of Forestry (CDF) inmate work crews will remove tamarisk and
Ailanthus with chainsaws and loppers as close to the ground as possible. Immediately after the cutting of the plants DFG scientific
aids will apply an herbicide treatment to the stems by painting them with a brush. Removed
vegetation will be burned on-site.
Re-vegetation will consist of gathering local seed and
cuttings. Vegetation to be restored may include: cottonwoods, willows, redbud, wild grapes,
elderberry, wild alder, and ash.
On the ground, monitoring in the second year will identify
what and where additional removal and re-vegetation will be necessary.
Photo-monitoring sites were established before the removal of the tamarisk.
These sites will document the change over time of the vegetation, water flow,
and erosion. Click here or on map to go to the photo plots.
On the map, red flags indicate the location of the plots. Click these flags to
see pictures of creek before and after removal.
For more information on Tamarisk or other invasive species see the Nature Conservancy’s Wildland Invasive Species page: http://tncweeds.ucdavis.edu/esadocs.html.
Links to Photo Plots: Post 100, Post 99, Post 98, Post 97, Post 96, Post 95, Post 94, Post 93, Post 92, Post 91, Post 90, Post 89, Post 88, Post 87.