Cal-IPC News
Protecting California’s Natural Areas
fr
om Wildland W
eeds
from
Weeds

Vol. 13, No. 2, Summer 2005

Quarterly newsletter of the California Invasive Plant Council

Forming a partner
ship tto
o
partnership
prevent plant invasions
through horticulture
Ivy (Hedera spp.) climbs in a Bidwell Park woodland
in Chico, site of this year’s Cal-IPC Symposium,
October 6-8. As part of our role in a growing partnership with the horticultural community, Cal-IPC is
pursuing funding for genetic studies of escaped Hedera
species in California in order to determine problem
species and support potential nursery actions.
(Photo: Steve Green, Friends of Bidwell Park)

Inside:
Nursery partnership ………………………….. 4
High schoolers tackle carnation spurge…. 6
Sesbania control on Dry Creek…………….. 7
Weed research at UC Riverside ………….. 12
…plus the 2005 Symposium!

From the Director’s Desk

Mapping the Lay of the Land
California
Invasive Plant
Council
1442-A Walnut Street, #462
Berkeley, CA 94709
(510) 843-3902
fax (510) 217-3500
www.cal-ipc.org
info@cal-ipc.org
A California 501(c)3 nonprofit organization

Protecting California’s natural areas
from wildland weeds through
research, restoration, and education.
Staff
Doug Johnson, Executive Director
dwjohnson@cal-ipc.org
Elizabeth Brusati, Project Manager
edbrusati@cal-ipc.org
Gina Skurka, Project Intern
gmskurka@cal-ipc.org
Board of Directors
Steve Schoenig, President (2005)
California Dept. of Food & Agriculture
Alison Stanton, Vice-President (2005)
BMP Ecosciences
Carri Pirosko, Secretary (2005)
California Dept. of Food & Agriculture
Jennifer Erskine-Ogden, Treasurer (2005)
U.C. Davis
Joe DiTomaso, Past-President (2004)
U.C. Davis Weed Science Program
Jon Fox (2005)
California Polytechnic University, San Luis Obispo

Last issue, we ran a Red Alert article on Japanese knotweed (Polygunum cuspidatum). Field
biologists were finding what they believe to be new infestations in Humboldt County.
Because the plant is rated by the California Department of Food & Agriculture on the list of
noxious weeds, historical maps of the remaining populations are available, and these
locations can be added—if indeed they are new— and monitored.
Such cases point out the importance of mapping. Observations at a particular place and time
are invaluable for tracking the dynamic geographic phenomenon of weeds. Was this here
before? How fast is it spreading? How and where is it spreading? These questions can only be
answered by careful observation over time, and the way to share the information gleaned
such observations is through maps.
Our strategies for controlling them weeds need to fully incorporate what we know about the
lay of the land. Outlier populations, leading edges, protected native habitat “sweet spots”—
our approaches can maximize effectiveness by being spatially adept at understanding the
ecological behavior of weed populations.
Regional efforts are making strides at mapping weeds. In northern California, Modoc,
Siskiyou, Shasta and Lassen counties are coordinating to aggregate their geographic data. In
southern California, groups have assembled data on Arundo donax over most watersheds.
New GPS software, like the Weed Information Management System (WIMS), are adding
power to field data collection.
Cal-IPC’s Mapping Committee is applying for funds to coordinate efforts statewide. The
lack of statewide maps of most weeds is a sizable gap in our ability to address invasive plants
at a landscape scale. As the revision of our inventory of California weeds nears completion,
we will initiate surveying counties to determine distribution at a coarse level for each of the
listed plants. Maps will help us envision ways to link our projects across the landscape—and
to show the need for a higher level of resources to accomplish weed work at a greater scale.

Mark Newhouser (2005)
Sonoma Ecology Center
Dan Gluesenkamp (2005)
Audubon Canyon Ranch
Bobbi Simpson (2005)
National Park Service – Exotic Plant Management Team
Jason Giessow (2005)
Santa Margarita/San Luis Rey Weed Management Area
Wendy West (2005)
U.C. Cooperative Extension, El Dorado County
David Chang (2006)
Santa Barbara Agricultural Commissioner’s Office
Joanna Clines (2006)
Sierra National Forest
Christy Brigham (2006)
Santa Monica Mountains National Recreation Area
Bob Case (2006)
California Native Plant Society

Affiliations for identification purposes only.
Last year of term noted.

Cal-IPC News
Summer 2005 – Volume 13, Number 2
Editors: Doug Johnson and Elizabeth Brusati
Cal-IPC News is published quarterly by the California
Invasive Plant Council. Articles may be reprinted with
permission. Submissions are welcome. We reserve the
right to edit all work.

2

Cal-IPC News

Summer 2005

Salmon Hole, Upper Bidwell Park, Chico (Steve Green photo)

Wildland Weed NewsNewsNewsNewsNews
Register Now for the 2005 Cal-IPC Symposium in Chico!
Early registration ends September 1. See details on page 10.

Got Weedy Items? Donate to our 2nd Annual Auction
Like last year, we’ll have a raffle and auction at our Thursday evening awards banquet at the
Symposium, and we need your donated items to make it go! We already have a Scotch
broom tea cup set and 1907 pampas grass post cards from a generous donor—do you have
a tool, book, piece of clothing or craftwork, bottle of wine, weekend retreat—OK, so this is
a broad, eclectic definition of weedy items! Please contact the organizers Wendy West and
Gina Skurka at wkwest@ucdavis.edu and gmskurka@cal-ipc.org. Thank you!
To help the National Park Service fight
invasive species and preserve threatened
natural resources, Sen. Ron Wyden (D-OR)
introduced legislation—S. 1288, The
Natural Resource Protection Cooperative
Agreement Act— to authorize the Secretary of
Interior to enter into cooperative agreements
with watershed councils, non-profits organizations, private landowners and county and
state governments to protect, maintain and
restore natural plant species and water
resources in and around national park lands.
The bill is co-sponsored by Sen. Daniel Akaka
(D-HI). (Medford News)
In April, House Resources Chair Richard
Pombo (R-Stockton) requested a report from
the Government Accountability Office to
identify lessons learned from a review of
events related to the infestation of the nation’s
forests by several major invasive insects and
diseases (i.e. the cause of Sudden Oak Death,
Asian long-horned beetle, and emerald ash
borer). The report will focus on federal efforts,
but will also include state and local government agencies. (National Invasive Species
Council newsletter, www.invasivespecies.gov)
Two bills sponsored by the California Native
Plant Society are moving through the
legislature without opposition. SB 502
(Kehoe) removes bias against native plants in
current statutes dealing with maintaining fire
breaks around structures and local weed
abatement actions. These laws now suggest
that native plants are the problem. AB 1466
(Laird) authorizes the state to enter into a
cooperative program with the federal
government and other Colorado Basin states
to undertake the removal of tamarisk from the
basin and reestablish native plants.
(www.leginfo.ca.gov)

The Coastal Environment Motor Vehicle
Mitigation (AB 658, Kuehl) would allow
coastal counties to charge a DMV vehicle
registration fee, whose proceeds would be
applied to local environmental projects that
address problems tied to roads, including
invasive plants. (www.leginfo.ca.gov)
Researcher Bill Bruckart at USDA is
conducting studies on a rust fungus
(tentatively identified as Puccinia acroptili)
that attacks Russian knapweed, investigating
its potential as a biocontrol agent. He needs
samples from infected plants. Infestations
have been found in Santa Barbara. For more
information, contact him at (310)619-2846
or wbruckart@fdwsr.ars.usda.gov.
Governor Janet Napolitano of Arizona
signed an Executive Order creating an
Arizona Invasive Species Advisory Council.
The EO requires state agencies to evaluate
their authorities and programs for invasive
species. (www.governor.state.az.us/press/
March05/040105~SDOC0731.pdf )
More from Arizona… Arizona’s national
forests will soon be providing a smorgasbord
for weevils, flies, moths, beetles and sheep.
The feast is part of a U.S. Forest Service plan
to treat 25 species of weeds on 135,000
acres of the Coconino, Kaibab and Prescott
forests in northern Arizona over the next ten
years. Bull thistle and Dalmatian toadflax
make up 90% of the weeds that infest
187,500 acres in Arizona. (Associated Press)
The May 22 issue of Parade Magazine (a
national Sunday newspaper insert) featured
a cover article on invasive species titled
“When Poison is Pretty.” Cal-IPC provided
information on the iceplant on the front
cover.

New Brochures
Available:
Biological Pollution
Describes impacts of invasive
plants for a general audience.
Great for visitors’ centers or public
events.

Don’t Plant a Pest!
Southern California
Adapted from original Bay
Area version, with invasives and
wildland-safe alternatives for
California south of the
Tehachapis.

Trees in California
Recommended alternatives to 18
invasive tree species in
California.

Central Coast
For San Luis Obispo and Santa
Barbara counties. Available soon.

For orders or samples, www.calipc.org or 510.843.3902

2nd Annual Cal-IPC

Photo Contest
Give us your best shots!
Categories:
Weed Impacts
Weed Workers in Action
Landscape (big infestations)
Specimens (single plants)
Before/After Projects
Humorous Weeds

Deadline September 1
Prizes for 1st, 2nd, and 3rd places in each
category. Winners will be chosen by the CalIPC board and displayed at the Symposium.
Digital photos preferred. Send entries to
edbrusati@cal-ipc.org or mail to Cal-IPC.
Cal-IPC News

Summer 2005

3

Featur
e
eature

Don’t Sell a P
est
Pest
A Ne
wP
artner
ship tto
o Pr
event Plant Inv
asions thr
ough Horticultur
e
New
Partner
artnership
Pre
Invasions
through
Horticulture
Sarah Connick and Mike Gerel, Sustainable Conservation
Cal-IPC is working with Sustainable Conservation and representatives from the horticultural
community to develop voluntary measures that
will address ongoing introduction of known
invasive plants. The partnership also hope to
improve screening for new plant introductions so
that future invasions can be avoided. This article
is adapted from a paper delivered at the 2004
Cal-IPC Symposium.
The horticulture industry has been an
important pathway for invasive plant
introductions in the United States, and a
number of plants known to be invasive in
California are widely available through
nurseries and garden centers in the state.
While substantial headway has been made in
the development of techniques for controlling
and eradicating invasive plants, relatively little
attention has been given to the development
of effective strategies for preventing new and
continuing invasions. After researching the
structure of the industry and efforts of others
working in this area, Sustainable Conservation
has established a multi-stakeholder partnership to develop and foster the implementation
of strategies for preventing new and continuing introductions of invasive plants through
the horticultural community in order to
protect California’s natural resources.
Invasive Plants and the Horticulture Trade
The horticultural industry has been an
important pathway for the introduction of
many known invasive plants. Reichard
(1997) determined that 85% of invasive
woody plants in the United States were
introduced for landscape trade, and estimated
that there is the potential for more than 1000
new invasive plants to be introduced through
this pathway (Reichard 2001). Stanton
(2002) determined that 53% of California’s
most invasive plants have horticultural origins.
While there are numerous individual
reports of invasive plants sold at stores, little
comprehensive data have been available to
understand fully the number of species and
extent of the availability of plants known to

4 Cal-IPC News Summer 2005

plants carried per wholesaler was 3.2, or 5.5
including varieties. Of the 13 plants having
varieties, each was sold by an average of 4.5
nurseries. One wholesaler carried 14 invasive
plants. Cal-IPC also reported on a 2003 retail
nursery survey conducted by University of
California Cooperative Extension Master
Gardeners in San Mateo and Santa Clara
counties. The Master Gardeners surveyed 23
nurseries looking for 25 invasive plants
included in the 1999 Cal-IPC list, and found
23 on sale (Table 2B).

Vinca major (periwinkle), a popular
ground cover, invades Garrapata State
Park. Photo: Bob Case
be invasive through wholesale and retail trade.
To better understand the situation, Sustainable Conservation and Cal-IPC compiled
information on the availability of known
invasive plants through the review of catalogs
and availability listings for 25 Californiabased wholesale nurseries. The nurseries were
selected to provide a representative crosssection of the industry based on size, specialty,
and location. Cal-IPC identified 52 plants
from the approximately 100 in its List of
Exotic Pest Plants of Greatest Ecological Concern
in California (Cal-IPC 1999) that have
potential horticultural value, treating
horticultural varieties separately.
Cal-IPC found that 32 of the 52 plants
were carried by at least one wholesaler (Figure
1). Thirteen of those 32 invasive plants also
had varieties that were sold by at least one of
the 25 growers surveyed. Cal-IPC found that
18 of the 25 growers carried at least one
invasive plant and 22 carried at least one
invasive plant or an invasive plant variety
(Figure 2A). The average number of invasive

California’s Horticulture Industry
Horticulture is the third largest agricultural industry in California, after dairy and
grapes. In 2001, it accounted for $13.2
billion in sales, and provided approximately
169,000 jobs. Approximately 27% of
California’s nursery plant production takes
place in San Diego County, and California
produces 21% of the nursery plants sold
nationwide (Hoy & Rodriguez 2003). On
the consumption side, California is the largest
nursery retailing state in the country, and sales
have been trending upward.
California’s horticulture industry is
diverse and highly fragmented. At the
wholesale level, plant material flows from a
wide variety of seed and live plant propagators
and growers to a wide range of retailers (Figure
3). The three main types of retail outlets are
in-store retail, mail order, and landscape
contractors. End customers vary widely from
homeowners to commercial establishments
and governmental purchasers, all of which
have different needs.
There are 2,930 wholesale nursery
producers in California (CDFA 2003), which
accounted for $3.1 billion in sales in 2001
(Hoy & Rodriguez 2003). The wholesale side
of this industry operates on low profit
margins, with high competitive rivalry, and
has low bargaining power relative to retailers.
Although the industry has experienced a
significant amount of consolidation in recent
years, some sources say it is stabilizing, and it
remains highly fragmented. Wholesale

Figure 1. Cal-IPC-listed invasive
plants available from CA wholesale
nurseries
(from 2004 Cal-IPC Survey)
Scientific name
Arctotheca calendula
Arundo donax
Cirsium vulgare
Cortaderia selloana
Cotoneaster lacteus
Cotoneaster pannosa
Cytisus scoparius
Eichhornia crassipes
Elaeagnus angustifolia
Ficus carica
Foeniculum vulgare
Hedera helix
Helichrysum petiolare
Hypericum perforatum
Ilex aquifolium
Iris pseudacorus
Lupinus arboreus
Mentha pulegium
Myoporum laetum
Myriophyllum aquaticum
Olea europaea
Pennisetum setaceum
Retama monosperma
Ricinus communis
Robinia pseudoacacia
Sapium sebiferum
Schinus molle
Schinus terebinthifolius
Sesbania punicea
Spartium junceum
Tamarix ramosissima
Vinca major

Common name
cape weed
giant reed
bull thistle
pampas grass
Parney’s cotoneaster
cotoneaster
Scotch broom
water hyacinth
Russian olive
edible fig
fennel
English ivy
licorice plant
St. John’s wort
English holly
yellow flag iris
bush lupine
pennyroyal
myoporum
parrot’s feather
European olive
fountain grass
bridal broom
castor bean
black locus
Chinese tallow tree
Peruvianpepper
Brazilian pepper
red sesbania
Spanish broom
saltcedar
periwinkle

growers face several pressing issues in addition
to concerns about invasive plants, including
pathogen control and increased regulation of
runoff water quality.
On the retail side, California’s horticultural industry accounted for $10.1 billion in
sales in 2001 (Hoy & Rodriguez 2003).
There are many plant retailers in California;
however, the greatest volume of plant sales is
concentrated in the big chain stores. The
hardware/home center market share has
grown rapidly in recent years, and the
relatively high bargaining power of the big
chains allows these retailers to put pressure on
margin and volume. At the same time that
these retail outlets handle large volumes of
plants, plants are only one of many types of

products they sell.
Landscape firms are also important retail outlets for plants. While no
data are available for California,
Americans spend approximately
$11.2 billion on landscape construction and installation, and approximately $10.7 billion on landscape
maintenance annually (First Research
2003). Landscape contractors
constitute an estimated 7-14% of
national nursery and grower sales
(ANLA 2004).
Catalog sales account for $3.1
billion in annual sales value nationally
(MGA 2003). Although catalogue
sales represent a relatively small
volume, they have the potential to
play a significant role in the introduction of invasive plants because of the
distributed nature of the business.

ecological impacts, as long as the listing would
not have a detrimental impact on agriculture.
Eleven new plants were added to the list in
2003. At the local level, there has been
increasing interest in ordinances banning the
sale of specific plant species.
Despite the attractiveness of regulation as
a strong tool for controlling business practices,
it is not clear that regulation alone is the most
effective tool for preventing new and
continuing introductions of invasive plants
(Wortman 2004). The issue of plant
invasiveness is complex and differs widely
according to plant species and geography. As
a result, several organizations have sought
nonregulatory means for preventing plant
invasions. Invasive plant councils across the
country are identifying and inventorying
invasive plants to raise awareness of problems
in their areas. Cal-IPC and other organizations have developed and disseminated
educational brochures on alternatives to
invasive plants.
In 2001, industry, academic, and
nonprofit organizations concerned about
invasive plants of horticultural origin came
together to develop voluntary codes of
conduct for nurseries, landscape architects,
botanic gardens, and garden clubs. Since
then, 35 organizations have voluntarily signed
the St. Louis Declaration Codes of Conduct
(Center for Plant Conservation 2001). The
Codes represent a significant step forward in
…continued page 14

Existing Prevention Efforts
There is no comprehensive
framework for regulating all pathways
of invasive plant introductions, or for
regulating all types of invasive plants
sold through the horticultural trade.
Federal authority for invasive plant
regulation and control is fragmented
across many agencies, and emphasizes
control of plants that have an adverse
impact on agriculture, as opposed to
ecosystems. The U.S. Department of
Agriculture has
banned a small
Figure 2. Cal-IPC-listed plants most widely
number of highly
invasive plants from
available in the nursery trade
importation and
A. Wholesalers (25 surveyed):
trade nationally. At
No. of Wholesalers
the state level, the
Hedera
helix
(English
ivy)
7
California Department of
Cortaderia
selloana
(pampas
grass)
5
Food and Agriculture
Cotoneaster
lacteus
(cotoneaster)
5
maintains a list of noxious
Schinus
molle
(Peruvian
pepper
tree)
5
weeds, and is responsible
for establishing appropriate
Varietals:
levels of regulatory action.
Pennisetum setaceum var. (fountain grass)
12
Thus, the listing of a plant
Hedera
helix
var.
(English
ivy)
9
as a noxious weed does not
Cortaderia
selloana
var.
(pampas
grass)
7
necessarily translate directly
Vinca major var. (periwinkle)
7
into a statewide sales ban.
Until recently, this list
B. Retailers (23 surveyed):
focused on plants that have
No. of Retailers
an adverse impact on
Hedera
helix
(English
ivy)
23
agriculture. In 1993,
Pennisetum
setaceum
(fountain
grass)
21
however, the listing
Vinca major (periwinkle)
21
authority was revised to
Helichrysum
petiolare
(licorice
plant)
17
include plants that have
Cal-IPC News

Summer 2005

5

From the Field

High School Student
ak
e On
Studentss T
Tak
ake
Carnation Spur
ge
Spurge
By Christy Brigham, Santa Monica National Recreation Area
A new invader has established a foothold
in the coastal bluffs near Malibu, California.
Euphorbia terracina (Geraldton carnation
spurge or false caper) is known from only two
locations in the United States—Southern
California and Pennsylvania. This species is
originally from Mediterranean Europe and is
an aggressive invader of shrublands in
Australia.
Carnation spurge is related to leafy
spurge (Euphorbia esula) but lacks that species’
vigorous rhizome. Carnation spurge in the
Malibu area invades any area of disturbance,
large or small. It can be found in fire fuel
modification zones surrounding houses, lots
that have been graded for construction, and
on gopher mounds in undisturbed coastal
sage scrub. Once seeds are exposed to light,
they germinate and grow rapidly. Within a
single year, plants can form large shrubs three
to five feet tall. The species forms dense
monocultures that exclude all native vegetation and provide little habitat value due to
their toxic milky sap. Plants are prolific
seeders and fruits explosively dehisce,
throwing seeds far and wide.
Carnation spurge now dominates several

acres of disturbed areas at Solstice Canyon in
the Santa Monica Mountains National
Recreation Area. This park is owned and
managed by the National Park Service and has
a long history of invasive species battles. Prior
to acquisition by NPS, several local groups,
such as the California Native Plant Society,
spent countless hours working in the canyon
to remove invasive species like periwinkle
(Vinca major) and fennel (Foeniculum vulgare).
When NPS received the site in 1993, they
realized that carnation spurge was a major
problem in the canyon.
Solstice Canyon is an important site for
restoration because it contains large areas of
intact coastal sage scrub, riparian communities
and chaparral. Its plant communities include
23% of all species native to the Santa Monica
Mountains, as well as rare plants such as alders
(Alnums rhombifolia) and Plummer’s baccharis
(Baccharis plummerae). The canyon also
provides habitat for endangered southern
steelhead trout and is popular with recreation
area visitors.
Since 2002, NPS has worked with local
school groups to remove carnation spurge and
restore disturbed areas by planting native
vegetation. The program, called
EcoHelpers, brings high school groups—
typically science classes—on one-day field
trips to the canyon to learn about invasive
species and help restore areas infested with

High school students
digging out Euphorbia terracina at
Solstice Canyon.
(Photos by Randy
Philips, NPS)

6 Cal-IPC News Spring 2005

carnation spurge. Students typically come in
groups of 30-50 and spend an hour learning
about the impacts of invasive species and
taking a short hike in the canyon. They then
alternate between hand pulling carnation
spurge (wearing gloves and long sleeves) and
planting native plants. Volunteers in NPS’
native plant nursery grow all plants for the
project from seed or stock collected locally.
Since the project started, 2,836 students have
visited the canyon to work on restoring
spurge-infested areas. More than 6,000
native shrubs and grasses have been planted
and a five-acre area has been restored.
The success of this project has depended
on numerous partners. The Los Angeles
County Agricultural Commissioner’s Office
assisted by performing carnation spurge
control in some large areas in preparation for
planting by the high school students.
Mountains Restoration Trust, a local nonprofit conservation group, partnered with
NPS on several restoration projects in Solstice
Canyon, including the EcoHelpers program.
The Los Angeles County Weed Management
Area also donated time and materials to the
project.
This is the final year for EcoHelpers in
Solstice Canyon. We have run out of large
areas appropriate for hand pulling and
planting by school groups. The remaining
small infestations of carnation spurge in the
canyon will be treated by park staff and
trained volunteers. EcoHelpers will continue
at a different park site, Zuma Canyon, where
students will focus on converting a weedy fuel
modification zone into a native grassland.
Contact the author at christy_brigham@nps.gov.

Controlling Red Sesbania in
Dry Cr
eek
Creek
By Peter Buck, Sacramento Area Flood Control Agency
Shannon Lucas, May & Associates
The Sacramento Area Flood Control
Creek to flow into the Sacramento River. Of
Agency, in partnership with Sacramento
approximately 44 miles of creek within the
County, Placer County, the City of Sacraproject area, pre-treatment mapping in
mento, and the City of Roseville, is conductSummer 2004 identified 26 miles (60%) that
ing a three-year project to remove the invasive were infested with red sesbania.
riparian weed red sesbania
The eradication project aims to restore
(Sesbania punicea) from Dry
Creek and its tributaries in
Placer and Sacramento Counties. The project is funded by a
Proposition 13 Flood Protection
Corridor Program grant
provided by the Dept. of Water
Resources. During Year 1
(2004), we removed 80% of
the mature red sesbania plants.
In 2005, the remaining mature
plants will be removed and
follow-up treatments will be
conducted for resprouting
stumps and emerging seedlings.
Red sesbania is a vigorously-growing riparian plant
native to South America. It
thrives in the California Central
Valley and spreads rapidly
Cutting red sesbania along Dry Creek (Photo by Peter Buck)
down waterways via floating
pods that contain seeds that may be viable for natural processes within Dry Creek, improve
many years. Since its initial detection in Dry
floodwater conveyance, and contribute to the
Creek, red sesbania has become an aggressive
elimination of this invasive plant regionally
and dominant species on stream banks and in- and statewide. Given that the species spreads
channel islands, altering river flow patterns,
by water flow, major elements of the project
displacing native riparian vegetation, limiting
include identifying and eliminating upstream
shoreline access, and increasing erosion. In
sources in order to contain the weed species,
heavily infested portions of the Dry Creek
identifying new populations downstream
watershed, red sesbania often comprises more
following project completion, and monitoring
than 50% of the biomass of emergent
and follow-up of treated areas to avoid
vegetation along the shoreline and on islands,
reinfestation of the creek by seeds remaining
causing canopy closures with a virtual
after the initial removal efforts.
biological “desert” underneath. Complex food
The project area supports valley elderwebs that are maintained by a diversity of
berry longhorn beetle (Desmocerus californicus
native wetland plants and aquatic habitats
dimorphus), a federally-listed threatened
become simplified or excluded. In addition,
invertebrate, and its host plant blue elderberry
the foliage and seeds of red sesbania are
(Sambucus mexicanus). Dry Creek and its
poisonous.
tributaries also support several anadromous
The Dry Creek watershed covers
fish species, including fall run Chinook
approximately 101 square miles in Placer and
salmon and federally protected steelhead.
Sacramento Counties. Dry Creek flows
Measures employed by this project to protect
through cities and unincorporated areas north these species and their habitat include
of Sacramento and eventually joins Steelhead
herbicide restrictions (regarding timing,

distance, formulations and application
methods) as approved by the US and
California EPA and NOAA fisheries, as well as
worker training and biological monitoring.
Red sesbania removal began in late
summer and fall 2004, starting at the
upstream extent of Dry Creek and its
tributaries and continuing downstream. The
primary method of removal was “cut-andpaint,” i.e. cutting the shrub (with hand or
power tools) near the base and immediately
painting the remaining stump with herbicide
(generally Aquamaster). Some younger, smaller
sesbania plants were pulled out by hand.
Biomass was then hauled by
hand, or “yarded” using ropes
or cables, into piles outside of
the Dry Creek floodplain,
then chipped and mulched.
Year 1 work also included
a public awareness campaign.
A brochure was prepared to
educate the public about red
sesbania, its harmful effects to
riparian communities, and the
Dry Creek project. This
brochure, along with a red
sesbania fact sheet prepared
by the Sacramento Weed
Warriors, was sent to landowners along Dry Creek prior
to our removal work. In an
effort to prevent further
introductions of red sesbania
from landscaped areas along
Dry Creek, approximately 30 nurseries within
the vicinity of the Dry Creek watershed were
contacted by phone to ask whether they
stocked red sesbania plants. A follow-up letter
was sent to these nurseries describing the
control project, as well as sesbania brochures
and Cal-IPC’s “Don’t Plant a Pest” brochure.
Year 2 activities will include two or three
follow-up treatments of resprouting sesbania
stumps and removal and/or treatment of new
seedlings beginning in March 2005, and
removal of the remaining mature red sesbania
plants in summer and fall 2005. Treatments
in Years 2 and 3 will include a combination of
herbicide application and green flaming, a
new technique that damages new growth via
focused, intense heat without posing a fire
hazard to surrounding vegetation. Future
goals include continued follow-up treatment
of new seedlings, public volunteer opportunities, and continuing awareness outreach.
Contact the authors at buckp@saccounty.net and
shannonlucas@mayandassociatesinc.com.
Cal-IPC News

Summer 2005

5

Boar
dR
eport
Board
Report

What’
What’ss the plan?
The Cal-IPC boar
d’
or 200
5 and be
y ond
board’
d’ss vision ffor
2005
bey
In April, Cal-IPC board members and staff met on Catalina Island
to discuss short- and long-range strategy for the organization. Staying
in tent cabins generously donated by the Catalina Island Conservancy,
we spent a weekend discussing which of many projects to pursue,
deciding how planned projects fit with current top priorities, and
identifying possible funding sources. In outlining plans for the next
two years, we focused on expanding our information resources,
continuing our promising work with nursery partners, ramping up our
advocacy for weed programs at the state and federal levels, and
providing new avenues for Cal-IPC members to play an active role.

comprehensive weed management manual that is updated regularly.
Our first workshop, scheduled for Oct.5 in Chico before the 2005
Symposium, will focus on control techniques. Future workshops may
also include project planning, mapping and monitoring, weed
identification, and restoration topics.
2. Continue work aimed at addressing the horticultural pathway
Cal-IPC is a central participant in the Partnership to Prevent
Invasive Plant Introductions through Horticulture with Sustainable
Conservation, The Nature Conservancy, and members of the horticultural community (see article page 4). Together, we are working to
identify which invasive plants to target and what actions will work best
to prevent introductions of invasive plants through the trade.
In conjunction with the partnership, Cal-IPC will be developing a
statewide program to educate nursery owners, other horticultural
professionals, and consumers on non-invasive alternatives. We are
coordinating with local weed workers around the state to produce
“Don’t Plant a Pest!” brochures for additional regions of California (see
page 3 for newly released versions). We will also be coordinating with
county groups, like those in Alameda and Marin counties, that are
beginning to work with local retail nurseries to sell only wildland-safe
plants.

1. Completing revision of the Invasive Plant Inventory and expanding our other weed information resources
Cal-IPC’s weed list committee has finished draft assessments of
approximately 300 plants for the 2005 revision of our California
Invasive Plant Inventory. All plant assessments are available on our
website, and we encourage you to check the analysis and provide
additional information for plants with which you are familiar. We will
incorporate comments received by the end of August into a printed
draft that will be distributed to attendees at the October Symposium
for its last review. The final print version will be ready in early 2006.
Because of the lack of regional data, the inventory assesses weeds at
a statewide level, and does not account for regional variations. Thus,
an immediate next step is to collect regional
mapping data to establish where each weed
is in the state. We envision a county-based
survey to establish the first coarse-level
mapping of weeds throughout the state,
and have applied for funding to coordinate
a statewide weed mapping data committee.
In an effort to develop a more detailed
statewide map of a single species as a pilot
project, we are partnering with Team
Arundo del Norte and the Santa Margarita/
San Luis Rey Weed Management Area in
San Diego County to map the statewide
distribution of Arundo donax. In the future,
we hope to develop an interactive web
portal where users can submit geographic
information on new invasions or range
expansions, providing up-to-date distribution maps. Such features will require a
significant upgrade to our website capacity. 2005 Cal-IPC Board of Directors, staff, and retreat host. Standing, from left: Dan Gluesenkamp,
We decided to offer Integrated Pest
Bobbi Simpson, Christy Brigham, Steve Schoenig, Carri Pirosko, Doug Johnson, Jenn Erskine
Management (IPM) field workshops, with Ogden, Gina Skurka, Alison Stanton, David Chang, Jon Fox, Bob Case. Sitting, from left: John
the eventual goal of also publishing a
Knapp (Catalina Island Conservancy), Mark Newhouser, Joe DiTomaso, Elizabeth Brusati, Wendy
West, Jason Giessow.

8 Cal-IPC News Summer 2005

3. Ramp up advocacy for weed programs
In 2005, Cal-IPC has taken a lead role in: organizing Day at the
Capitol (at which the heads of the Resources Agency and the Dept. of
Food & Agriculture spoke, and attendees made 80 legislative visits);
coordinating California’s largest delegation to National Invasive Weeds
Awareness Week in DC; mobilizing local events for California Invasive
Weeds Awareness Week; and hosting a bus tour for Sacramento
legislative staff to view local weed control projects. These efforts
represent a significant increase in outreach capacity, and we plan to
continue on this trajectory.
Through the many legislative visits made on Day at the Capitol in
March (see the Spring issue Cal-IPC News), we have maintained
contact with several offices to explore potential funding avenues for
Weed Management Areas and invasive plant control projects. While
the state’s continuing budget problems make obtaining funding
difficult, we will continue to raise the profile of the invasive plant issue
among legislative staffers, especially those from urban areas who may be
less aware of the issue.
Economic impacts of invasive plants is one of the best ways to
convince decision makers that the issue is serious. We plan to develop
outreach materials that draw on a compilation of existing published
research on economic impacts. To assist with this effort, Cal-IPC will
host an intern from the Biological Invasions graduate program at UC
Davis this summer who will prepare a literature review and write a draft
report. We are also supporting the development of a decision-analysis
model weighing control costs versus known impacts of a particular
weed to agriculture, recreation, and natural ecosystems.
Educating the public is an important aspect of advocacy. We have
found many groups—classes, garden clubs, homeowners’ associations,
etc.—interested in having a presentation on invasive plants. Our

Board member Joanna Clines pulls some tocalote on Catalina Island.
outreach committee is developing a speakers’ bureau that will be
available for making presentations to groups in their area that request
information on invasive plants. We are designing short PowerPoint
slide presentations with speaker’s notes for several audiences, including
garden clubs and general college classes.
4. Provide avenues for Cal-IPC members to play an active role
We are a member-driven organization, and all of the above
programs depend in large part on participation from our knowledgeable, committed members. Below are listed some productive avenues
for active involvement that Cal-IPC members.

Member Involvement
Comment on our plant assessments. Members are our eyes and ears
in the field, and most weeds do not have adequate published
information, making field observations key. Add additional literature
citations or personal observations that will improve the accuracy and
documentation of the inventory. We are currently taking comments
for the updated list until August 30, but new observations are always
welcome. Visit www.cal-ipc.org and follow the link in the center
column.
Be a Cal-IPC weed mapping contact for your county. We will be
surveying for all listed weeds in each of the state’s counties, and will
need individuals to serve as primary contacts for collecting information at a local level. Contact dwjohnson@cal-ipc.org.
Join the Cal-IPC speakers’ bureau. We will provide you with
PowerPoint presentations, speaker’s notes, and brochures. When
someone from your area requests a talk, we will contact you. Or, even
better, volunteer to give a talk to a group in your area. Contact
edbrusati@cal-ipc.org.
Come to this year’s Cal-IPC Symposium in Chico. Over 300 weed
workers gather to share the latest on biology and management, with

local field trips, too (see page 10). And consider preparing a
presentation or poster for next year. Full details at www.cal-ipc.org.
Plan to attend Invasive Weeds Day at the Capitol, March 2006.
Spend a day in Sacramento educating legislators and agency manaers
about invasive plants in your county. We especially need participants
from the far northern and southern ends of the state. It’s a great
opportunity to meet fellow weed workers from around the state and
make a difference at the capitol. Contact wkwest@ucdavis.edu.
Plan an event for California Invasive Weeds Awareness Week, July
2006. It’s never too early to brainstorm ideas! Our website has
suggestions for organizing and publicizing activities for Weeds Week
or similar events. Visit www.cal-ipc.org.
Submit an article to Cal-IPC News. Let your fellow weed workers
know about an innovative project, a new tool, an exciting event, etc.
Contact edbrusati@cal-ipc.org.
Join the California Weed Talk listserv. Sharing information is what
it’s all about, and this is an easy way to do it. Visit www.cal-ipc.org for
instructions on joining.
Cal-IPC News

Summer 2005

9

The 14th Annual Cal-IPC Symposium

Prev ention Reinvention:
Protocols, Information, and Partnerships to Stop the
Spread of Invasive Plants
Oct
ober 6-8, 200
5, Calif
ornia St
ate Univ
er
sity
October
2005,
California
State
Univer
ersity
sity,, Chico

Early registration: $210 by September 1
Join us for our 14th annual Symposium!
The Cal-IPC Symposium is the ideal place to learn the latest in invasive
plant biology, management, and policy issues from researchers and
practitioners working around the state. Invited speakers, contributed
papers, working groups, field trips, posters, and trade exhibits make the
Symposium the most comprehensive overview of wildland weed work in
California.
The meeting venue is Bell Memorial Union on the campus of
California State University, Chico. Chico’s Bidwell Park, one of the largest
municipal parks in the country, has one of the state’s most active local
weed control efforts (the park also played the part of Sherwood Forest for
The Adventures of Robin Hood in 1938). Big Chico Creek runs through
campus, and downtown Chico is right next store. The award-winning
Sierra Nevada Brewery calls Chico home (as does the National Yo-Yo
Museum). Lassen Volcanic National Park is an hour away.
This year’s theme addresses the crucial role of prevention in weed
programs. Three sessions of invited speakers, including Jerry Asher from
BLM in Oregon (retired) and Eric Lane from the Colorado Department
of Agriculture, will describe aspects of successful programs that prevent
the spread of invasive weeds. Five contributed paper sessions and a poster
session cover the full spectrum of wildland weed topics, from control
techniques to GIS mapping, ecosystem processes to DNA identification.
Four Saturday field trips explore weed projects in the Sacramento River
National Wildlife Refuge, Bidwell Park, the Sutter Buttes, and Stony and
Red Bank creeks. And eight working groups and discussion groups give
you the opportunity to go in depth on a topic with your fellow weed
workers. Plus Red Alerts, legislative updates, our awards banquet, auction,
sponsor exhibits, and photo contest…

Invited Paper Sessions:
Protocols and Practices for Stopping Weed Movement
Inventory and Prediction for Stopping Weed Spread
Partnerships for Early Detection and Rapid Response

Contributed Paper Sessions:
Control and Management
GIS to DNA: New Tools
Successful Programs and Partnerships
Safe and Effective Use of Herbicides
Biology and Ecology of Weeds

10 Cal-IPC News Summer 200
5
2005

Poster and Trade Exhibit Session
Special Lunchtime Speaker:
Joseph Silveira, Sacramento River National Wildlife Refuge, “The
return of natural diversity to Great Valley wildlife habitats”

Working and Discussion Groups
Cal-IPC Board committees will be running four Working Groups to
plan strategy and enlist support for their projects:
Weed List
Horticulture
Mapping
Outreach
In addition, four Discussion Groups will invite attendees to share
information on specific topics:
Weeds in riparian areas, wetlands and sensitive habitats
Trees and shrubs
Weeds and fire management
Grasslands

Awards Banquet
Jake Sigg Award for Vision and Service
Golden Weed Wrench Award for Land Manager of the Year
Catalyst Award for Inspiring Action
Weedzilla Award for NPS Manager of the Year

DPR Continuing Education Credits
We have applied to the California Department of Pesticide Regulation for 2 hours of Law and Regulations credit, 12 hours general
credit for paper sessions, and 4 hours general credit for field trips.

Saturday Field Trips
The Sacramento River As It Was: Ordbend Park and Llano Seco
Ranch
Peace Valley at the Sutter Buttes
Invasive Weed Control in Chico’s Renowned Bidwell Park
Arundo and Tamarisk in the North: Stony and Red Bank Creeks

Full program, travel information, and
registration materials available at
www.cal-ipc.org

NEW THIS YEAR!

Wildland Weed Field Course
Wednesday, October 5, Chico
This one-day, hands-on field course focuses on control techniques. The course will benefit new weed workers and
oldtimers alike by combining a comprehensive overview of field techniques with presentation of the latest cutting-edge
technology.
Topics include:
Fundamentals of program design
Mechanical methods
Grazing, fire and biocontrols
Herbicides
Integrating methods
Propagation and revegetation

Instructors include:
Joe DiTomaso, UC Davis
Carri Pirosko, CA Dept. of Food & Agriculture
Dan Gluesenkamp, Audubon Canyon Ranch
Ken Moore, Wildlands Restoration Team
Rob Wilson, Farm Advisor Lassen County
Mark Heath, Shelterbelt Builders, Inc.
(affiliations for identification only)

Registration $85 with Symposium registration, $100 without
Materials at www.cal-ipc.org

Upper Bidwell Park, site of one of this year’s field trips. (Photo by Steve Green, Friends of Bidwell Park)
Cal-IPC News

Summer 200
5
2005

11

Resear
ch
esearch

Inv
asiv
e Plant
esear
ch at UC Riv
er
side
Invasiv
asive
Plantss R
Resear
esearch
River
erside
By Jodie S. Holt, Botany and Plant Sciences Department, University of California, Riverside (jodie.holt@ucr.edu)
As a follow-up to the article, “Teaching
Weeds: California university invasive plant
programs” (Cal-IPC News Summer 2004), we
wanted to highlight the abundant research
underway at UC Riverside on the biology,
ecology, and management of invasive plants.
Several faculty members in the Department of
Botany and Plant Sciences have both
undergraduate and graduate students in their
laboratories working on a wide range of weed
species in a variety of ecosystems. This
research ranges from very basic projects in
ecology, genetics, and physiology to very
practical projects in management of invasive
species and conservation of native species.
Here we highlight several of those labs and
the research of their students. Departmental
information, as well as links to all professors’
homepages, at www.plantbiology.ucr.edu.

lesser inputs from agriculture (as ammonium).
Concentrations of extractable soil N may be >
5 times greater in soils affected by atmospheric
deposition than in rural areas at a distance
from urban sources. Weedy invasive plants
such as red brome (Bromus madritensis) tend
to be more nitrophilous than many native
plants, and can take up N and grow faster in
response to elevated N. One important
consequence of N deposition is an increase in
wildland fire frequency as vegetation becomes
converted to exotic annual grassland. Current
research underway at Joshua Tree National
Park shows that the exotic Mediterranean split
grass (Schismus barbatus) responded to N
fertilization during a year of slightly aboveaverage precipitation (2003/2004). Leela
Rao, a Ph.D. student, is measuring vegetation
response to N as part of her dissertation, and
Drs. Andrzej Bytnerowicz and Mark Fenn of
the Forest Service Fire Lab in Riverside are
Edith Allen, Professor of Plant Ecology and
measuring atmospheric N inputs across the
Cooperative Extension Natural Resources
park. The decline of native biodiversity in
Specialist
southern California may also be related to N
Anthropogenic N deposition and
invasive plant species. Experimental evidence deposition. Ph.D. candidate Robert Cox is
undertaking a survey of listed and sensitive
from the Allen lab has been mounting over
plant species of western Riverside County and
the last 10 years that anthropogenic nitrogen
the Coachella Valley, and measuring the
deposition is increasing the abundance of
invasive plant species in coastal sage scrub and abundance of invasive species associated with
sightings of rare plants. These are being
Mojave Desert vegetation. Plant-available N
correlated with the modeled map of N
emissions in southern California originate
deposition created by Gail Tonnesen of UCR’s
primarily from automobiles (as nitrate) with
College of Engineering.
Restoration to control
invasive plant species. As
native vegetation goes into
decline, restoration is an
important tool for conservation and for controlling
exotic species. Grassspecific herbicide (Fusilade)
has been used to control
brome grasses with good
results, followed by seeding
with native coastal sage
scrub shrub species.
Additional studies are
Students working on artichoke thistle at Crystal Cove State Park underway by Robert Cox
— Jared Stephens (undergraduate), Robin Marushia and
who was able to reduce
Ginger White (graduate students). (Photo by the author)
exotic grass cover and

12 Cal-IPC News Summer 2005

increase native forbs in coastal sage scrub
stands for 5 years following Fusilade application, and by Ph.D. candidate Robert Steers,
who applied Fusilade to creosote scrub to
control Mediterranean split grass and increase
native forbs in the shrub understory. Still
another study is underway by Robin
Marushia, a Junior Specialist working with the
Allen and Holt labs, in weedy abandoned
farmland in SW Riverside County, where
solarization to kill the seed bank proved the
most effective technique to assure successful
establishment of native vegetation.
Norman C. Ellstrand, Professor of Genetics
and Director, Biotechnology Impacts Center
An area of interest in the Ellstrand lab is
gene flow and hybridization as factors in the
evolution of increased invasiveness. Hybridization between species and subspecies has
been linked to the creation of invasive lineages
in several systems. One such system is radish
(Raphanus) in California. In the mid-1800s,
two radish species, cultivated radish (R.
sativus) and jointed charlock (R.
raphanistrum), were introduced to California.
Since their arrival they have freely hybridized
into a complex that has invaded almost the
entire geographic range of the state. While
hybrid-derived radish has been successful in
California, it is not clear that hybridization
itself is the mechanism that is directly
responsible; rapid adaptive evolution may
have played a role in the lineage’s ability to
expand its range. Caroline Ridley, a Ph.D.
student, is testing both hybridization and
rapid local adaptation as complementary
explanations for the evolution of invasiveness
in California wild radish.
Another Ph.D. student, Jutta Burger,
studies weedy rye (Secale sp.), a persistent
annual weed of the western US that is either
of hybrid or of cereal (S. cereale) rye origin.
She is investigating the genetic correlates of
weediness of cereal rye in order to identify the
possible origins of populations and to test for
local adaptation in weedy populations along a
latitudinal gradient. By understanding how
this species has spread so successfully she

hopes to better understand how genetics,
especially hybridization, and local conditions
interact to change introduced species into
major invaders.
Janet Garcia is a new Ph.D. student at
UCR who works between the Ellstrand and
Holt labs. Her dissertation project focuses on
the genetic relatedness of artichoke thistle,
Cynara cardunculus, an invader of coastal
grasslands, to the two conspecific crop
varieties C. cardunculus var. scolymus (globe
artichoke) and C. cardunculus var. altilis
(cardoon). She is interested in identifying the
weedy type in California (putative var.
sylvestris) and understanding its origin in
relation to the two crops.
Jodie S. Holt, Professor of Plant Physiology
and Chair, Department of Botany and Plant
Sciences
Research in the Holt lab focuses on
mechanisms and genetics of plant invasion in
particular habitats and how these mechanisms
might be manipulated for successful management. One current project focuses on the
physiology and population ecology of
artichoke thistle and the mechanisms by
which it invades coastal grasslands. Dr.
Virginia White recently completed her
dissertation on the environmental physiology
of artichoke thistle in which she studied traits
contributing to invasiveness, sites most
suitable for establishment, and competitive
interactions with native and exotic grasses.
Robin Marushia’s recently finished M.S.
Thesis addressed patterns of seed dispersal
and seedling establishment in artichoke
thistle, in which she demonstrated that in
field settings most seeds dispersed within 5
meters of the parent plant, while in the
absence of impediments created by vegetation, dispersed seeds may travel 40 meters or
more. Another project, conducted by Dr. Ian
Gillespie as a Postdoctoral Researcher, focuses
on demography of artichoke thistle in order to
understand the life history stages most
important to population growth and most
vulnerable to control.
Dr. Rana Tayyar, Staff Research Associate,
recently completed a field experiment at UCR
to determine the effect of Roundup and
Transline herbicides on artichoke thistle
applied at early resprouting, late resprouting,
bolting and flowering stages. Both herbicides
were most effective in controlling plants at the
late resprouting stage (100% mortality) and
least effective at the flowering stage (48%
mortality). Dr. Tayyar has another experiment

underway to investigate genetic variation
within and among field patches of artichoke
thistle, which will allow us to assess the
relative contributions of asexual and sexual
reproduction to spread in grasslands. Random amplified polymorphic DNA (RAPD)
markers will be used in this analysis to
distinguish clones from seed-derived plants.
Using a combination of demographic and
environmental data we are also applying
modeling approaches for scheduling the
timing of control of this species.
Several projects either underway or
recently completed in the Holt lab focus on
invasion of riparian ecosystems by Arundo
donax (giant reed). Mike Rauterkus recently
completed his M.S. Thesis, which

other colonizing plant species. Greenhouse
experiments have shown that lateral spread of
giant reed rhizomes may be enhanced by
nitrogen fertilization and is most likely to
occur in autumn, and biomass accumulation
is highest under moderate shading. Results of
this work are being used in experiments
conducted by Dr. Virginia White to test
approaches for giant reed removal and
restoration of native riparian species in order
to prevent reinvasion.
We have recently begun to address the
physiological basis for the recent rapid spread
of Brassica tournefortii, Sahara mustard, into
southwestern US deserts. This research is a
collaborative project with Dr. Matt Brooks of
the USGS in Henderson, NV. In this project,
Robin Marushia is assessing differences in
phenology (seasonal timing) between Sahara
mustard populations from desert and nondesert environments, and comparing patterns
of phenology with those of other invasive
mustard species (B. geniculata, shortpod
mustard, and B. nigra, black mustard) that
differ in range. She is also conducting field
experiments to assess differences in phenology
between Sahara mustard and native Mojave
annuals and to measure the impacts of Sahara
mustard on native plant density, growth, and
fecundity at different levels of invasion.
These experiments will inform management
by defining priority levels of Sahara mustard
density that are most likely to impact native
annual plant populations. New Ph.D.
student Melanie Stalder, who is interested in
chemical ecology and allelopathy, will study
the impacts of Sahara mustard on the desert
rhizosphere (underground ecosystem).

Graduate student Lauren Quinn deep
in Arundo. (Photo by the author)

Related Research at UCR
Several other departments at UCR focus
on invasive species. The Center for Conservation Biology (CCB) (www.ccb.ucr.edu) assists
in the conservation and restoration of species
and ecosystems by facilitating the collection,
evaluation, and dissemination of scientific
information. The Center for Invasive Species
Research (cnas.ucr.edu/centers/cisr.html)
addresses pest and disease invasions by
fostering cooperation and coordination of
research efforts among UC campuses, USDA,
the California Department of Food and
Agriculture, and the agricultural industry.
Finally, individual faculty in several other
departments on campus conduct research on
invasive species. For more information, visit
the website of the UCR College of Natural
and Agricultural Sciences (cnas.ucr.edu).

addressed physiological characteristics of giant
reed in comparison to native riparian species,
and the impacts of giant reed on environmental resources and conditions in riparian
habitats. Lauren Quinn, a current Ph.D.
student, has investigated the invasion
behavior of giant reed. In research where
giant reed rhizomes were planted in three
(already invaded) southern California riparian
ecosystems, establishment varied with
environmental factors but occurred in all
locations, indicating that giant reed is able to
succeed in many habitat types. However, in a
field experiment at UCR’s experiment station,
she found that plant community composition, particularly the shrub component,
reduced the invasion success of giant reed and

Cal-IPC News

Summer 2005

13

Horticultural invasions continued…
addressing horticulture as a pathway for
invasive plant introductions, and provide a
solid foundation for developing practices
throughout the horticultural community to
prevent new and continuing introductions.
At the same time, however, they provide
broad direction and significant additional
work is needed to translate them into action.
Preventing Horticultural Invasions
Sustainable Conservation is a nonprofit
organization, based in San Francisco, which
uses innovative partnerships to promote
voluntary conservation in the private sector.
In 2003-04, Sustainable Conservation
conducted research on the horticulture
industry and invasive plants. Based on our
findings, we determined that an effective
approach for developing and fostering the
implementation of strategies for preventing
introductions of invasive plants of horticultural origin in California would be through a
multi-stakeholder partnership that engages
representatives of the industry, consumer,
nonprofit, environmental, and academic
communities concerned with these issues.
In June 2004, Sustainable Conservation
convened a forum for stakeholders to share
their perspectives on the nature of the
problem and challenges in addressing it, and

to assess the need for
Figure 4. Organizations participating in the
such an effort. The
California Partnership for Preventing Invasive
group concluded that a
collaborative effort to
Plant Introductions through Horticulture
develop and foster
implementation of
American Nursery and Landscape Association
strategies for preventing
American Society of Landscape Architects, Northern CA Chapter
invasive plant introducCalifornia Association of Nurseries and Garden Centers
tions through nurseries is
California Department of Food and Agriculture
needed in California. It
California Invasive Plant Council
identified several key
California Landscape Contractors Association
challenges, especially the
California State Floral Association
critical importance of
Home Depot
bringing the right people
Mail Order Gardening Association
to the table with respect
Monrovia Nursery
to both the constituency
The Nature Conservancy
an individual represents,
UC Davis RIDNIS Program (Reducing the Introduction and
and the commitment of
Distribution of Non-native aquatic Invasive Species)
that person’s organization
California Agricultural Commissioner and Sealers Association
to the process. In
Sustainable Conservation
addition, the group saw
UC Cooperative Extension, Master Gardeners Program
coming to agreement on
UC Santa Cruz Arboretum
the definition and
determination of
“invasiveness” as a significant hurdle to be
Conservation convened the Steering Commitcrossed. Other key challenges included
tee for this effort, which named itself the
consumer preferences for particular plants, the California Partnership for Preventing Invasive
diversity of the audiences that this effort
Plant Introductions through Horticulture or
needs to reach, and the need for high-quality
Cal-PPIPIH (Figure 4). The group adopted a
scientific information.
statement articulating its purpose:
In December 2004, Sustainable

Figure 3. Chain of horticultural products from production to consumers
(chart by Sarah Connick and Terri Kempton, Sustainable Conservation)

“To develop and foster implementation of
strategies for preventing new and continuing
introductions of invasive plants through the
horticultural community in order to protect
California’s natural resources.”
The group agreed to move forward with
its work on two parallel tracks. One track will
come to agreement on a definition of
invasiveness and evaluation criteria using
examples to inform this work, and then
identify invasive plants that are used and
propagated in the horticultural community.
The other will develop the strategies needed
to prevent new and continuing introductions
of plants that are identified as invasive,
including education and outreach approaches
to industry and consumer communities.
Sustainable Conservation has hired a new
project manager to coordinate the program;
progress will be reported in upcoming issues
of Cal-IPC News.
Contact the author at sconnick@suscon.org, or
see the Sustainable Conservation website at
www.suscon.org.

14 Cal-IPC News Summer 2005

Austr
alia pr
ohibit
ation o
ustralia
prohibit
ohibitss import
importation
off 3,335 plant
plantss
From the Australian Ministry of Fisheries, Foresty, and Conservation
June 1, 2005

Partnership, cont’d…
References
American Nursery and Landscape Association
(ANLA) 2004. Personal communication between J.
Forrester and ANLA staff.
California Department of Food and Agriculture
(CDFA) 2004. Directory of nurserymen licensed to
sell stock in California. www.cdfa.ca.gov/phpps/pe/
nursery.htm
California Invasive Plant Council (Cal-IPC) 1999.
The CalEPPC List: Exotic Pest Plants of Greatest
Ecological Concern in California. 12 pp. Available:
www.cal-ipc.org
Center for Plant Conservation. 2001. The St. Louis
declaration on invasive plant species. Available:
www.centerforplantconservation.org/invasives/
First Research, Inc. 2003. First Research industry
profiles: Nurseries. July 7, 2003.
Hoy, C. and Rodriguez, A. M. 2003. Economic
Impact California Horticulture Industry 2003: A
summary of “Economic contributions of the
California nursery industry.” California Association
of Nurseries and Garden Centers: Sacramento.
Mailorder Gardening Association (MGA) 2003.
www.mailordergardening.com
Pimentel, D., Lach, L., Zuniga, R., and Morrison,
D. 2000. Environmental and economic costs of
nonindigenous species in the United States.
Bioscience 50:53-65.
Reichard, S. H. and Hamilton, C. W.1997.
Predicting invasions of woody plants introduced into
North America. Conservation Biology 11(1):193203.
Reichard, S. H. and White, P. 2001. Horticulture
as a pathway for invasive plant introduction in the
United States. Bioscience 51:103-113.
Stanton, A. E. 2002. Developing alternatives to
invasive landscaping plants. Proceedings of the
California Exotic Pest Plant Council Symposium.
6:111.
Wortman, M. 2004. Foreign invaders threatening
global biodiversity and the public hasn’t noticed—
yet. Environment Yale: The Journal of the School of
Forestry & Environmental Studies, Fall:3-11.

the Quarantine Proclamation 1998) has been
amended to reflect the completion of Stage
One of the review. The Australian Government announced earlier this year that
Biosecurity Australia would accelerate the
review of the permitted seeds list.
Biosecurity Australia consulted widely on
a list of 4,000 species recorded as weeds
overseas and not yet considered present in
Australia. The Cooperative Research Centre
(CRC) for Australian Weed Management
prepared the list for the Worldwide Fund for
Nature. Following the consultations,
Biosecurity Australia determined 3,335
species on the list were not present in
Australia. Australia will permit imports of
these species only if a weed risk assessment
determines their weed potential in Australia is
low. “The review will enhance Australia’s
favourable pest and disease status by ensuring
Australia does not import known weedy
species,” Senator Macdonald said. “The
second stage of the review will remove genuslevel listings from the permitted seeds list.
This means Australia will target individual
plants rather than groups of plants.”
Fort the second stage of plant evaluation,
Biosecurity Australia is preparing information
for extensive consultation with over 400
stakeholders including the World Wildlife

A report called “Jumping the Garden
Fence: Invasive Garden Plants in
Australia and their Environmental and
Agricultural Impacts”, was commissioned
by World Wildlife Fund- Australia and
prepared by senior scientists. In its 173
pages, the document examines impacts of
invasive garden plants on both agriculture
and natural ecosystems. Garden plants
comprise 70% of Australia’s total
(agricultural, noxious, and natural
ecosystem) weed population; their cost is
estimated at AU$4 billion annually. The
report names key offending species and
calls for stricter monitoring and enforcement.
Fund, Australian Seeds Federation and the
CRC for Australian Weed Management, as
well as research to determine which species in
over 2,900 currently permitted genera are
present and/or commonly traded in Australia.
“I expect the complete review of the permitted genera to be finalised by the end of next
year,” Senator Macdonald said.
Further information available at
www.daff.gov.au/biosecurityaustralia.

Critic’
w ar
ds
Critic’ss Choice A
Aw
ards

The Australian Government has
prohibited importation of 3,335 potential
weeds to protect the nation’s agriculture and
environment. Conservation Minister Senator
Ian Macdonald said removal of the potential
weeds marked the end of the first stage of a
major project to remove whole groups
(genera) from the list of permitted seed
imports. “This is an important next step in
protecting Australia’s agriculture and environment from potential weeds,” Senator
Macdonald said.
The permitted seeds list (Schedule 5 of

Cal-IPC News

Summer 2005

15

Book Reviews
Invasive Plants of Range and Wildlands and Their
Environmental, Economic, and Societal Impacts.
Edited by Celestine L. Duncan and Janet K. Clark
(2005 Weed Science Society of America)
222 pp. $20.00 through www.wssa.net/publications
This paperback summarizes literature on 16 invasive plants, including
13 species found in California (three thistles, three knapweeds,
perennial pepperweed, purple
loosestrife, leafy spurge, downy brome,
medusahead, dalmation toadflax, and
saltcedar). Information was compiled
from published literature and a
questionnaire sent to weed managers to
provide updated distribution information for each species. The book focuses
on summarizing impacts—to livestock
and wildlife, plant communities,
community function, soil and water
resources, human health, and economics. (Any benefit provided by each
species to livestock or wildlife is also
noted.) Though little economic data
exists for many of these plants, the
book’s summary of exisiting studies performs an important function by
establishing the foundation that will help researchers identify data
gaps.
The book is not mean as a taxonomic guide, and there are no
photographs (though each species is shown on the back cover). While
certainly not an extensive reference, this book provides a concise review
of a few key species of interest to many land managers. The lengthy
citation list for each species forms a good foundation for researchers or
those wanting more detailed information.

Wildly Successful Plants: Northern California
By Pam Peirce (2004 Sasquatch Books) 306 pp
$24.95 from www.sasquatchbooks.com
This book is aimed at convincing
gardeners that they can have a
beautiful garden with minimal
effort by choosing plants adapted
to northern California’s climate(s).
It focuses on 50 plants, with
detailed descriptions of their
required growing conditions. Pam
Peirce is an instructor of horticulture at City College of San
Francisco and co-founder of the
San Francisco League of Urban
Gardeners (SLUG).
Though the title of the book
makes one somewhat apprehensive at first, Peirce does a good job of
balancing the needs of novice gardeners with the issue of invasive
plants. She mentions wildland weeds repeatedly throughout the book,

16 Cal-IPC News Summer 2005

and specifically recommends against some of the worst species, such as
brooms or pampas grass. She also tells gardeners how to act responsibly
by not throwing bulbs or other plant material over their fence,
watching to see if plants are escaping out of the yard, and being
especially careful if they live near a creek or open space. Cal-IPC’s list is
referenced and explained, as is the official state Noxious Weed List.
Most of the plant recommendations are appropriate, but four species in
the book are of some concern. Vinca major and Digitalis purpurea, both
rated as Medium level invasives in the current draft of our updated list,
are featured plants, though the author does mention their potential
invasiveness. Peirce makes a stronger case for the invasiveness of ivy
(Hedera helix and H. canariensis) and warns gardeners not to allow the
vines to climb and fruit due to potential dispersal by birds.
We recommend this book as a gift (along with a “Don’t Plant a
Pest!” brochure) for your friend or relative who’s interested in gardening and can’t understand why you want to pull out all the pretty
Scotch broom from the hillsides. The many photographs of gardens
and flowers will attract those looking for pretty plants for their yards,
and hopefully readers will pay attention to the information on invasive
garden escapees and consider the issue of wildland weeds when
choosing new plants.

Plants and Landscapes for Summer-Dry Climates of
the San Francisco Bay Region
(2004, East Bay Municipal Utility District) 320 pp. $34.95 from
www.ebmud.com
This book, with its large format (9” x 12”) and multitude of gorgeous
photographs, would almost be worth buying simply to put on your
coffee table. An update to EBMUD’s Water-Conserving Plants and
Landscapes for the Bay Area, it
contains a catalog of 650
plants with charts in the
back to organize information
by growth form and light or
water requirements. Although it focuses on plants
suitable for the Bay Area,
introductory chapters cover
topics appropriate for most
of California, including tips
for working with summerdry and winter-wet climates,
an explanation of microclimates, and designing
landscapes for fire safety on
the wildland-urban interface.
The first page of the plant
catalog mentions the fact that many plants have been found to be
invasive, but states that because invasiveness varies so much by location
and climate, the authors chose to address the issue by noting potential
invasiveness in individual species descriptions. Several of the recommended plants, such as cotoneaster, are listed by Cal-IPC, and their
descriptions make a brief mention of possible invasiveness in specific
areas. This is another book to give with a “Don’t Plant a Pest!” brochure, and one that reminds us of the ongoing need to integrate
invasives information with recommended plant lists being developed
for water conservation, fire safety, power line safety, and other concerns.

New Members and Donors
Thank you for your generous support! This list reflects donors and new members since the last newsletter.

Donations
Robert Berman (CNPS, Pacific Grove)
Susan G. Duncan (Oakland)
John Ekhoff (Long Beach)
Judy B. & Arnie Fishman (Los Angeles)
Betty Kipp (CNPS, Berkeley)
Robert P. and Averil Leach (West Sacramento)
David Loeb (Berkeley)
Judith Lowry (Larner Seeds, Bolinas)
William McCoy (CNPS, Berkeley)
T. Charles Moore (Sunnyvale)
Val Page (Mojave Desert RCD, Apple Valley)
Jake Sigg (San Francisco)
Don Stiver (CNPS, El Cerrito)
Noreen A. Trombley (NPS, Yosemite)
Jean Vandevort (Felton)
Peter Warner (CA State Parks, Little River)
Annette Wheeler (Los Altos Hills)
Matthew & JoAnn Zlatunich (San Francisco)

Donations to Cape Ivy Biocontrol
California Native Plant Society:
East Bay Chapter
Marin Chapter
Los Angeles-Santa Monica Mountain Chapter

Ha
ve y
ou seen this plant?
Hav
you
Mystery Senecio found in So Cal

San Luis Obispo Chapter
Santa Clara County Chapter
Carolyn Halde (San Francisco)
Greg Archbald (Nevada City)
Judy and Arnie Fishman (Los Angeles)

New Members
Flo Anderson (Weed), Clare Aslan (UC Davis), Darin Banks (Prairie
Village, KS), Katharyn Boyer (SFSU Romberg Tiburon Center,
Tiburon), Cathy Boze (Mariposa County Dept. of Agriculture,
Mariposa), Terrel Brand (Oakland), Ernest Bryant (Santa Barbara),
Tim Butler (Oregon Dept. of Agriculture, Salem, OR), Mary Carroll
(Santa Barbara), Penny Dalton (Sebastopol), Jonna D. Engel (CINMS,
Santa Barbara), Arne Johanson (Poway Blue Sky Reserve, San Diego),
Ann and Peter Jones (CNPS – Marin Chapter, Woodacre), Celia
Kutcher (CNPS Orange County, Capistrano Beach), Monique Lau
(San Rafael), Samuel Leininger (UC Davis, Sacramento), Virginia
Moran (Ecological Outreach Services, Grass Valley), Deborah North
(EDAW, Davis), Mary Shea (Vernal Consulting, Concord), David
Sundstrom (CNPS South Coast Chapter, Rancho Palos Verdes),
Bobbie Stephenson (Kingfisher Environmental, Inc., San Diego),
Justin Watson (JDW Industries, Arroyo Grande), Stephen Winter
(San Luis NWR Complex, Los Banos), Fred Thomas (CERUS
Consulting, Chico)

straight, erect stems. It spreads laterally as older stems lay onto the
ground and sprout new verticle shoots. The involucres are about 4 mm
wide and the flowers are yellow.
Senecio spec. nov. resembles Senecios of South America and
…cont’d next page

By Scott White, scottbioservices@earthlink.net
This apparently undescribed Senecio has been collected at several
sites in San Diego and Orange Counties over the past few years. It
grows in wetland margins at roadsides, seeps, alkaline flats, and
probably stream channels. It is a shrub, about 1 – 1.5 m tall, with

Cal-IPC News

Summer 2005

17

Readings &
Resources
Cal-IPC website: We have added and
reorganized several sections on our website.
The Landscape Alternatives page is now called
For Gardeners, and will point visitors to
“Don’t Plant a Pest!” brochures and FAQs on
species like sweet broom. A section called For
Land Managers includes links to the Weed
Workers’ Handbook and a Weed Control
page with links to control information for
plants rated High or Medium in the latest
Cal-IPC list. You can now connect directly to
individual species accounts in the WWH
without downloading the full book. Control
information will continue to be expanded in
the coming months. Finally, we have a new email address (info@cal-ipc.org) for general
inquiries.
Federal register notice: The U.S. Fish and
Wildlife Service published in the Federal
Register a final list of bird species to which the
Migratory Bird Treaty Act does not apply
because they are not native to the United
States and have been introduced by humans
everywhere they occur in the nation. The list
is required by the Migratory Bird Treaty
Reform Act of 2004.
Herbicide report: The Invasive Spartina
Project has released a report describing the
proposed use of imazapyr to control invasive

cordgrass in San Francisco Bay. The report
concludes that imazapyr offers an improved
risk scenario over the existing treatment
regime with glyphosate.
Fact sheets: The EPA has web links to
information on microbial biopesticide
products. All three products are expected to
be especially useful in battling invasive plants:
first Chodrosterum purpureum product,
registered October 2004; second C. purpureum
product registered March 2005; and Dyer’s
Woad Rust, registered June 2002.

Outreach materials: The Center for Invasive
Plant Management, with support from the
Western Integrated Pest Management Center,
recently developed “The Invasive Plant
Resource Guide: a Big Book for a Big
Problem.” It provides reference materials
developed by many agencies and organizations to support invasive plant management
and education efforts. A web-based version
will be available soon.
Website: The US Forest Service has a new site
to serve as a portal for information on their
invasive species programs at the national,
regional, district, and forest levels.

Cape Ivy Research: The annual research
report for the Biological Control of Cape Ivy
Project is now available as a pdf on the CalIPC website’s publications page.

Senecio, cont’d…
Australia. A formal description prepared by
Brant Primrose and the late Ted Barkley will
be published soon. While it remains
unknown to botanical science in its native
range, it has somehow reached southern
California and spread across two counties.
Horticulture is the most likely agent of
dispersal. Perhaps it is being grown in
specialty nurseries, or traded among garden
hobbyists.
Though it is possible that it is native to
California, that seems very unlikely. It is big,
conspicuous, grows in densely populated
regions, and is generally found in disturbed
places such as roadsides. It threatens to
become a serious invasive pest in native
riparian vegetation.
Your help is needed! Please document

18 Cal-IPC News Summer 2005

any occurrences in the wild or in cultivation
with photographs, or better, by collections.
Forward specimens with labels (date, location,
collector) to one of these herbaria:
Herbarium, Rancho Santa Ana Botanic
Garden, 1500 N. College, Claremont, CA
91711, [909.625.8767]
Herbarium, Dept. of Botany and Plant
Sciences, University of California,
Riverside, CA 92521, [909.787.3601]
Herbarium, San Diego Natural History
Museum, P.O. Box 121390, San Diego,
CA 92112-1390, [619.255.0247]
Herbarium, Plant Pest Diagnostics Center,
CA Dept. of Food & Agriculture, 3294
Meadowview Rd., Sacramento, CA
95832-1448

Recipes: Why just kill weeds when you can
eat them? The National Park Service’s Alien
Plant Working Group has a link to recipe
pages from several invasive plant groups.
Sorry, at this time we have no plans to serve
kudzu sorbet at the Cal-IPC Symposium
dinner.
Herbicide guidelines: The Nature Conservancy has posted two guides for herbicide use
in natural areas on its Invasive Species
Initiative website. The guides are “Safe
Herbicide Handling in Natural Areas: a
Guide for Land Stewards and Volunteer
Stewards” and “Upkeep and Maintenance of
Herbicide Equipment: a Guide for Natural
Areas Stewards.”
Website: The San Francisco Estuary Institute
is launching an internet-based guide to exotic
organisms as a resource for educators,
researchers and others. It contains photographs, descriptions and ecological information on several common marine invaders in
San Francisco Bay. They plan to expand it to
include additional species in the San Francisco
Estuary and elsewhere on the North American Pacific Coast.
Book: Reclaiming Lost Provinces: A Century
of Weed Biological Control in Queensland
has been published by the Queensland
Department of Natural Resources and Mines.
It is available for AU$35.95 plus shipping.
The author is Craig Walton, who says this
volume would be a good companion to
Biological Control of Invasive Plants in the
United States (see book reviews).

Public Service Announcement: Following last
year’s “Knotweed!” video, the Whatcom
County (WA)Noxious Weed Board has
produced a second public service announcement to be shown before movies in
Bellingham, WA. The 30-second“Gill Man”
spot features a damsel in distress and a swamp
creature, focusing on aquatic invasive species.
It can be viewed at The Nature Conservancy’s
website (free Quicktime player needed to
watch it). Coming soon is a longer DVD on
invasive garden plants.

The WILDLAND WEED CALENDAR
Sierra Nevada Alliance
12th Annual Conference
July 29-31, 2005
North Lake Tahoe, CA
Speakers, workshops, field trips, and networking with Sierra conservation leaders.
www.sierranevadaalliance.org
“Invasive Plants: Perspectives, Prescriptions,
and Partnerships”
August 16-17, 2005
Philadelphia, PA
Contact: jlm@pobox.upenn.edu
Western Regional IPM Symposium
“Water, Wildlife & Pesticides in the West: Pest
Management’s Contribution to Solving
Environmental Problems”
Portland, OR
Contact: R.S. Melnicoe, 530-754-8378
8th International Conference on the Ecology
and Management of Plant Invasions
September 5-12, 2005
University of Silesia in Katowice, Poland.
www.emapi.us.edu.pl
World Conference on Ecological Restoration
September 12-18, 2005
Zaragoza, Spain
Organized by the Society for Ecological
Restoration. www.ecologicalrestoration.net
Santa Barbara WMA’s Anuual Noxious
Weeds Seminar
September 14, 2005
Solvang, CA
The theme of this year’s seminar is riparian
weeds management. www.countyofsb.org/
agcomm/wma/WMASeminar.htm

2nd New England Invasive Plant Summit
September 17-18, 2005
Framingham, MA
Convened by Invasive Plant Atlas of New
England and New England Invasive Plant
Group. invasives.eeb.uconn.edu/ipanel
7th Annual California Weed Management
Area Meeting
September 19- 20, 2005
Woodland, CA.
Funding and grantwriting; networking
between WMAs; state and federal funding
legislation updates; weed control technology
vendors; GIS and mapping; education and
outreach; new weeds and new control tools.
New this year – Educational Display Contest!
Contact: Steve Schoenig, (916)-654-0768 or
SSchoenig@cdfa.ca.gov
Biological Invasions IGERT Fall Symposium
September 21, 2005
Davis, CA
A forum for discussion on biological invasions
relating to the nursery and aquarium trades.
www.cpb.ucdavis.edu/bioinv/
32nd Natural Areas Conference
“Changing Natural Landscapes: Ecological
and Human Dimensions”
September 21-24, 2005
Lincoln, NE
www.unl.edu/plains
North American Weed Management Assn.
13th Annual Conference
September 26-29, 2005
Manhattan, KS
www.nawma.org

Quotable:

“A lot of people ask, ‘What are you trying to do? Make
it look like it did before the Europeans got here?’…
But you can never make it look like that. What we
want is a functioning ecosystem.”

John Knapp, Catalina Island Conservancy
Orange County Register, May 6, 2005

Know of an event that should be posted here?
Please contact edbrusati@cal-ipc.org.
7th Biennial State of the Estuary Conference
Oakland, CA
October 4-6, 2005
Focusing on connections between the
watershed, delta, and San Francisco Bay, with
sessions relating to habitat restoration,
estuarine water supplies, and water quality.
www.abag.ca.gov/events/estuary
Cal-IPC Wildland Weed Field Course
One-day hands-on field course focusing on a
variety of control techniques.
October 5, 2005
Chico, CA

Cal-IPC Symposium
“Prevention Reinvention: Protocols, Information and Partnerships to Stop the Spread of
Invasive Plants”
October 6-8, 2005
Chico, CA
See pages 10 and 11. www.cal-ipc.org
Nevada Weed Management Association
October 11-14, 2005
Reno, NV
Contact: Sue at donaldsons@unce.unr.edu
California Society for Ecological Restoration
(SERCAL)
“Restoring the Heart of California”
October 19-22, 2005
Bass Lake, CA
Topics include restoration project funding,
linking classroom to the field, restoration and
ranching, and more.
www.sercal.org
North American Plant Protection Organization Annual Conference
October 17-21, 2005
Puerto Vallarta, Mexico
www.nappo.org
Southwest Vegetation Management Association Annual Meeting
November 2-4, 2005
Phoenix, AZ
Contact: Patti Fenner (602) 255-5386
www.swvma.org
Cal-IPC News

Summer 2005

19

Cal-IPC Membership Form
We’re working to protect California’s wildlands from invasive plants—join us!
Cal-IPC’s effectiveness comes from a strong membership, including scientists, land managers, policy makers, and concerned citizens. Please
photocopy the form below, complete, and mail with your payment. Additional donations are always welcome to support our projects; we are a
501(c)3 nonprofit organization, and donations beyond regular membership rates are tax deductible.
Individual
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Contributing
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Life
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Joint Cal-IPC/CNGA
$70
Cal-IPC/SERCAL/CNGA
$95
Student/Volunteer
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Institutional
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$150
Contributing
$300
Patron
$600
Sustaining
$1,000
Small company
or Nonprofit
$100

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Ways to join:
Mail: send this form with check (made out to “Cal-IPC”) or credit card
info to Cal-IPC, 1442-A Walnut Street #462, Berkeley, CA 94709
Fax: fax form with credit card info to 510/217-3500
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Phone: call us at 510/843-3902 and provide contact and credit card info

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