Newsletter Vol 14 Issue 1, 2006 – California Invasive Plant Council

Cal-IPC News
Protecting California’s Natural Areas
from Wildland Weeds

Vol. 14, No. 1, Spring 2006

Quarterly Newsletter of the California Invasive Plant Council

Invasive plants
reaching higher
ground

Plants such as bull thistle (Cirsium vulgare)
are reaching high-elevation sites like Yosemite’s
Tioga Pass. Bull thistle received a Moderate
rating for its statewide impacts in Cal-IPC’s
recently-released Invasive Plant Inventory.
Photo: Bob Case.

Inside:
Legislation to Renew WMA Funding…………………. 4
A New Treatment for Arundo ………………………….. 6
Does Glyphosate Harm Amphibians? ……………….. 8
Scientists’ Recommendations on Ornamentals …. 13

From the Director’s Desk

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
Dan Gluesenkamp (2006)
Audubon Canyon Ranch
Mark Newhouser, Vice President (2006)
Sonoma Ecology Center
Wendy West, Secretary (2006)
U.C. Cooperative Extension
Jennifer Erskine Ogden, Treasurer (2006)
U.C. Davis
Steve Schoenig, Past President (2006)
California Dept. of Food & Agriculture

Strength in partnership
Some things in life can be accomplished alone, but controlling invasive plants is not
one of them (though many individuals make valiant and valuable efforts). The articles in
this issue reﬂect the power of partnership.
Many of Cal-IPC’s goals entail working with other groups that are discovering the
impact of invasive plants in their own efforts. This greatly expands the potential impact of
our work. Our partnership with nursery and landscape trade organizations, for instance, has
built new trust and the potential to eliminate known invasives from use in California horticulture. It establishes a great avenue for educating the public about invasives, as well.
Our partnership with agricultural groups such as the California Farm Bureau Federation and California Cattlemen’s Association provides a strong alliance with which to approach the legislature regarding invasive plant programs and policies. Initial funding for the
state’s network of Weed Management Areas came about because of this partnership, and we
are currently working together for renewed funding. And it was only a few short years ago
when the state would have lost the USDA ARS biocontrols research lab in Albany without
the coordinated intervention of environmental and agricultural advocates. the partial list of
supporters for AB 2479 on page 4 shows the breadth of this partnership.
We also partner with those in the business of invasive plant control, from ecological
consultants to herbicide manufacturers, by offering exhibit space at our Symposium. It is
important for restoration workers to have access to information on tools and services available in the marketplace, both from businesses themselves and from outside evaluators.
Partnership is not simple. It requires deﬁning the boundaries of mutually beneﬁcial collaboration, and building trust in working together. But the rewards are signiﬁcant, both in
the intended goals as well as the new relationships. There may be no more important way to
gauge our own strength and vitality than by the partners who want to work with us.

David Chang (2007)
Santa Barbara Agricultural Commissioner’s Ofﬁce
Joanna Clines (2007)
Sierra National Forest
Christy Brigham (2006)
Santa Monica Mountains National Recreation Area
Bob Case (2006)
California Native Plant Society
Chris Christofferson (2007)
Plumas National Forest
Jennifer Drewitz (2007)
Yolo County Resource Conservation District
Jason Giessow (2006)
Santa Margarita/San Luis Rey Weed Management Area
John Knapp (2007)
Catalina Island Conservancy
Marla Knight (2007)
Klamath National Forest
Brianna Richardson (2007)
Montgomery Law Group, LLP
Afﬁliations for identiﬁcation purposes only.
Last year of term noted.

Cal-IPC News

Spring 2006 – Volume 14, Number 1
Editors: Doug Johnson and Elizabeth Brusati
Cal-IPC News is published quarterly by the California
Invasive Plant Council. Articles may be reprinted with
permission from the editor. Submissions are welcome.
Mention of commercial products does not imply endoresement by Cal-IPC. We reserve the right to edit all work.

Cal-IPC News Spring 2006

Draft Policy on Integrated Weed Management
The Cal-IPC Board of Directors drafted this policy statement in order to clarify Cal-IPC’s
basic position on invasive plant management. If you would like to comment on this draft
statement, please write to us at info@cal-ipc.org or the address in the box at left.
Invasive plants cause serious damage to California’s wildlands. Land managers
and scientists have developed many methods to eradicate or control invasive plants,
including mechanical, chemical, cultural and biological control methods. Speciﬁcally, these methods include: hand tools for cutting or uprooting; heavy equipment;
herbicide application; grazing; prescribed ﬁre and other heat treatments; mulching
and tarping; competitive plantings; and release of host-speciﬁc insects or pathogens.
Typically, the goal is to apply control methods for a limited time in order to promote
the restoration of a self-sustaining native habitat.
Deciding which methods to use for a given project is based on many factors—effectiveness, ecological impacts, human health risk, cost, and availability of materials
and labor. Evaluating these factors and selecting the best set of methods for a given
project is generally called Integrated Pest Management (IPM) or Integrated Weed
Management (IWM).
Cal-IPC supports the practice of IWM, in which all available methods are considered and evaluated scientiﬁcally for beneﬁts and risks. Professional land managers
should evaluate the impacts of both invasive plants and control methods when selecting appropriate methods for a speciﬁc project or program.

Wildland Weed NewsNewsNewsNewsNews
15TH ANNUAL CAL-IPC SYMPOSIUM

Research and Management: Bridging the Gap
OCTOBER 5-7, SONOMA DOUBLETREE HOTEL, ROHNERT PARK
SAVE THE DATE! This year’s theme addresses the need for communication between those who conduct research and those who
manage and restore land. Registration opens June 1. The preliminary program will be mailed to Cal-IPC members in July.

ABSTRACTS FOR CONTRIBUTED PAPERS are due June 1. Instructions are at www.cal-ipc.org.
PRE-SYMPOSIUM FIELD COURSE October 4 – Tools for Early Detection Programs. Learn how to identify invasive plants, collect voucher specimens, design a monitoring program, and integrate GPS into your projects. Registration opens June 1.

DONATE ITEMS FOR THE CAL-IPC RAFFLE! We need your weedy items – useful, decorative, or just creative. Artwork, books,
weed worker tools, gift certiﬁcates for activities or restaurants… Contact Marla Knight, maknight@fs.fed.us or (530) 468-1238 to
donate.

PHOTO CONTEST: Show off your camera skills to your fellow weed workers in the 3rd Annual Photo Contest! Instructions for
submission are at www.cal-ipc.org. Categories include: Specimen, Landscape, Impacts, Weed Workers, Before & After, and Humor. Deadline September 1. Winners will be announced at the Symposium.

The U.S. Forest Service has completed
an Environmental Impact Statement for
Region 6 (WA and OR) on invasive plants.
It includes economic costs and projections
of different control methods, and potential
costs of delaying management efforts.
www.fs.fed.us/r6/invasiveplant-eis
The New York Times described unintended
consequences of a biocontrol project in
Montana. A gall ﬂy released to control
spotted knapweed has become a food source
for deer mice, causing mouse populations
to triple and raising fears of hantavirus. The
New York Times, April 4, 2006, D2
The State of Oregon added yellow ﬂoating
heart, garlic mustard, policeman’s helmet,
and yellow ﬂag iris to its Noxious Weed
Quarantine on January 13, 2006. www.
oregon.gov/ODA/PLANT/weed_index.shtml
Non-native plants that are in the presence
of their natural enemies do better in their
introduced ranges than those that have
escaped their natural enemies. Researchers at
the Georgia Institute of Technology found
that non-native herbivores, including cattle,
rabbits and goats, can encourage the spread
of invasive plants, while native herbivores,
are far more effective in reducing their
number. Most previous assessments of this

“natural enemies hypothesis” focused on insects. Although insects reduce plant growth
and biomass, vertebrate herbivores are often
larger and thus more commonly kill plants
outright, creating a stronger impact on plant
communities. Science, March 10, 2006
Paul Gobster, a social scientist with the US
Forest Service, compared the terminology
used in outreach materials and popular

CAL-IPC UPDATES…
INVASIVE PLANT INVENTORY
It’s here! The 2006 Cal-IPC
Invasive Plant Inventory
rates the impact, potential
for spread, and current
distribution of more
than 200 invasive
plants in California.
Copies may be purchased through the
Cal-IPC website
or by calling
(510) 843-3902.
THE USE OF FIRE AS A TOOL
FOR CONTROLLING INVASIVE PLANTS–
See p. 12.

literature on invasive species to that used in
restoration. He suggests that invasion biologists’ focus on fear may backﬁre with the
public, and instead encourages an emphasis
on removal of invasives as part of a more
positive message on restoration and preservation of native habitats. Cal-IPC founding
member Jake Sigg is pictured leading a community restoration day.
Ecological Restoration, December 2005.
AQUATIC DPP– Cal-IPC has received
funding from the California Department of Food and Agriculture to
produce a “Don’t Plant a Pest!”
brochure for aquatic
plants. It will be a statewide brochure, similar to
the existing Trees version,
and will complement the
regional brochures. Target
availablility is late 2006.
SPANISH DPP TRANSLATION
– Mission Resource Conservation District has acquired funding
to translate the Southern California “Don’t Plant a Pest!” brochure
into Spanish. They expect to go to
print this summer.

Cal-IPC News Spring 2006

Policy

Working to Renew Weed Management Area Funding
February and March were busy
months for Cal-IPC’s legislative activities.
This time of year, we join with a number
of other organizations that are concerned
about invasive plants to organize and
participate in two events: National Invasive
Weeds Awareness Week in Washington,
D.C., and Invasive Weeds Awareness Day
at the Capitol in Sacramento. Our activities are coordinated through the California Invasive Weeds Awareness Coalition
(CALIWAC). This year’s activities were
more exciting than usual because we are
working to support passage of a bill in the
state legislature that would restore funding
to California’s network of Weed Management Areas and allow them to continue
their work.
Day at the Capitol
Cal-IPC took the lead role in organizing the Third Annual California Weeds
Awareness Day at the Capitol in Sacramento, March 8, 2006. The event was
energized by the last-minute introduction
of AB 2479 to provide Weed Management
Area funding.
Morning presentations included
information on Weed Management Areas,
the California Biodiversity Council’s work
to coordinate agencies on invasive species issues, and the California Agricultural
Commissioners and Sealers Association
and California Department of Food and
Agriculture (CDFA)’s work to revise the
state noxious weed rating system. In the

SUPPORTERS FOR AB 2479
AB 2479 (Cogdill) would renew funding
for the state’s network of Weed Management
Areas (WMAs) at $2.5 million. Cal-IPC
has helped organize grassroots support for the
bill. This is a partial list of organizations
that have expressed ofﬁcial support, which
number more than 80 at press time. The full
list—and instructions on sending a letter—is
available at www.cal-ipc.org.
Statewide Organizations:
CA Agricultural Commissioners & Sealers Assn.
CA Assn. of Resource Conservation Districts
CA Cattlemen’s Assn.

Cal-IPC News Spring 2006

of 2,015 populations of high priority weed
infestations; 2) effective treatment of more
than 128,421 acres of weed infestations;
3) leveraging a 3-to-1 match from outside
grant funding and in-kind donations and
services; and 4) development of new local partnerships between public agencies,
private landowners, agriculturalists and
conservationists, and 5) outreach programs
reaching 88,803 people.
National Invasive Weeds Awareness Week
Cal-IPC Board Member Bob Case visits
Congresswoman Ellen Tauscher’s ofﬁce at
National Invasive Weeds Awareness Week.
afternoon, ﬁfty attendees met with 45 legislative ofﬁces and distributed information to
all other representatives’ ofﬁces, including
those of key committee staff.
Cal-IPC is working to build support for
AB 2479. Introduced in February, the bill
would provide $2.5 million in funding for
Weed Management Areas through CDFA.
California’s Weed Management Area program was created in 1990 and expanded in
2000. The funds expired in June 2004, and
the program has been without funding since
then.
California’s WMA program has grown
to 45 WMAs covering all 58 counties.
Many entities participate in WMAs, including federal, state, and local agencies, land
trusts, farmers and ranchers, and nonproﬁt
organizations. The program’s accomplishments include: 1) permanent eradication
CA Council of Land Trusts
CA Farm Bureau Federation
CA Forest Pest Council
CA Invasive Plant Council
CA Native Grasslands Association
CA Native Plant Society (CNPS)
CA Society for Ecological Restoration
Regional Council of Rural Counties
Sierra Club California
Trust for Public Land

Local organizations:
Agricultural Commissioner’s Ofﬁce of Colusa
County (and 4 other Ag. Depts.)
Big Sur Land Trust
Butte County Resource Conservation District
(and 6 other RCDs)
Cache Creek Conservancy

The Seventh Annual National Invasive Weeds Awareness Week was held in
Washington, DC on February 26 – March
3, 2006. Each year, a team of Californians
from the California Invasive Weeds Awareness Coalition (CALIWAC) attends the
event to learn what fellow weed workers
around the United States are accomplishing
and to push for invasive weeds legislation.
This year’s team included: Nelroy Jackson;
Andrea Fox, CA Farm Bureau; Carl Bell,
CA Weed Science Society; Mark Lockhart,
Trinity Co. Agricultural Commissioner;
Gina Skurka, Cal-IPC/CDFA; Elizabeth
Brusati, Cal-IPC; Jake Sigg, California
Native Plant Society (CNPS); Bob Case,
CNPS/Cal-IPC; Dan Gluesenkamp, Audubon Canyon Ranch/Cal-IPC; and Steve
Schoenig, CDFA.
While in Washington, Team CALIWAC visited the ofﬁces of the entire California Congressional delegation, meeting
with staff of 24 legislators, including Senators Boxer and Feinstein, and leaving folders
Catalina Island Conservancy
CNPS Alta Peak Chapter (and 8 other chapters)
East Bay Municipal Utility District
Friends of Bidwell Park (Chico)
Friends of Switzer Canyon (San Diego)
Garrapata Creek Watershed Council (Monterey)
Golden Gate Audubon Society
Land Trust for Santa Barbara County
L.A. & San Gabriel Rivers Watershed Council
Marin Conservation Corps
Mojave Water Agency
Palos Verdes Peninsula Land Conservancy
San Bruno Mountain Watch
Santa Barbara Audubon Society
Santa Clara County Parks & Recreation Dept.
Santa Lucia Conservancy (Carmel)
Solano Land Trust
Sonoma Land Trust

Visit the new Cal-IPC webpage!

The Cal-IPC website has been completely reorganized and has a brand-new look. It has more extensive
information than before and is easier to use, thanks to design by Carina Merrick. Now featuring:
New sections on impacts of invasive plants, biocontrol, and policy
Interactive Invasive Plant Inventory database
Expanded “Don’t Plant a Pest!” information
Online book and brochure orders
Online registration for Field Courses and Symposium

www.cal-ipc.org
of information at the remaining ofﬁces. We
also held three private agency meetings with
US Department of Agriculture-Agricultural Research Service on biocontrols, with
USDA Animal Plant Health Inspection Service on Weed Management Area funding,
and with the Department of Transportation
on roadside management.
Through efforts after the trip, the ofﬁces of Congressmen Joel Heﬂey (R-CO)
and Mike Thompson (D-CA) agreed to
co-author a Dear Colleague letter asking
their Congressional colleagues to sign a
letter requesting that the Appropriations
Committee provide appropriations for the
Noxious Weed Control and Eradication
Act of 2004, P.L. 108-412, for ﬁscal year
2007. The Act would provide $15 million
nationally to Weed Management Areas (the
original language speciﬁed $100 million),
and California, with its well-developed program, will be in a good position to compete
for these federal funds if we maintain state
funding. It was signed into law in late 2004
but has not been funded. The letter received
24 signatures, including California Representatives Bono, Calvert, Costa, Davis,
Filner, Herger, Hunter, Pombo, Radanovich,
Tauscher, Thompson, and Woolsey.
Finally, FICMNEW presented CALIWAC with an award in recognition of its
work “raising awareness and public education related to invasive plant management in

the nation’s most populous state” and gave
Team CALIWAC member and NIWAW
organizer Nelroy Jackson the Lifetime
Achievement Award, declaring that “getting
people together is Nelroy’s specialty.”
For More Information

California’s Weed Management Areas,
www.cdfa.ca.gov/weedhome
AB 2479 at the ofﬁcial California Legislative
Information site, leginfo.ca.gov.
Noxious Weed Control and Eradication Act
of 2004, P.L. 108-412, at thomas.loc.gov.

View the updated list of supporters for AB
2479 at www.cal-ipc.org.

California’s NIWAW delegation: From left, Bob Case, Steve Schoenig, Jake Sigg, Dan
Gluesenkamp, Elizabeth Brusati, Gina Skurka, Andrea Fox, and Carl Bell.

Cal-IPC News Spring 2006

Tools and Techniques

Low-Volume Foliar Treatment of Arundo Using Imazapyr
by Bill Neill, Riparian Repairs and Team Arundo Angeles
The author has supervised tractor mowing
and mulching of approximately 35 net acres of
Arundo and has ﬁve years’ experience applying
imazapyr herbicide in urban riparian areas of
Los Angeles County. Mention of product names
is provided for information only and does not
imply endorsement by Cal-IPC. Photos by the
author.
Relatively new to California, imazapyr
herbicide is an effective tool for controlling
Arundo using an unconventional “low volume” foliar treatment method. The recent
registration of imazapyr’s aquatic formulation named Habitat® makes the herbicide
more widely useful and discussion of application methods more relevant to Arundo
control programs.

Arundo, and somewhat greater coverage
will control short Arundo resprouts plus
waxy-leafed, difﬁcult-to-kill invasive trees
common in Southern California urban
riparian areas, such as Brazilian peppertree
and Mexican fan palms.
In either case, after herbicide treatment
the dead Arundo can be left standing, so that
it will gradually disintegrate; or the dead

Conventional foliar spraying of tall
uncut Arundo with glyphosate herbicide is
typically a “high volume” operation, employing crews with power pumps, hoses and
ladders to liberally coat all of the exposed
foliage with dilute herbicide mixture at application rates of 60 to 100 gallons per acre.

In contrast, foliar treatment of Arundo
and invasive trees using imazapyr herbicide
can employ a “low volume” method, with
delivery rates of only 10 gallons of spray
mixture per acre.
In the low-volume method, herbicide
mixture is lightly sprinkled on target foliage,
thus minimizing runoff, or applied with
a few rapid slashing movements using a
jet stream nozzle. In either case, contacting about 20 percent of the foliage surface
area is sufﬁcient for controlling tall uncut

Cal-IPC News Spring 2006

Alternatively, where Arundo stalks grow
through and drape over shorter native plants
such as mulefat, the herbicide application
is conﬁned to the exposed upper leaves of
recumbant Arundo stalks.
Consequently, where Arundo clumps
are intermixed with non-target vegetation,
less preparatory work is needed to compact
the Arundo and clip off embedded tree
branches, compared to the high-volume
foliar treatment method using glyphosate.
A second beneﬁt is that because the
liquid volume applied per acre is less, compared to high-volume spraying, the labor
requirement is reduced. A single applicator
using a backpack sprayer with a full tank
and jet stream nozzle can treat a quarter
acre of Arundo clumps without needing to
reﬁll repeatedly.

Comparison of Foliar Application Methods

For treating large Arundo stands that
are isolated from native vegetation, highvolume foliar applications of glyphosate are
rapid, nearly 100% effective, and relatively
inexpensive, compared to laborious cutting using chainsaws. Where Arundo is
intermixed with native trees, preparatory
work is required to separate target Arundo
from non-target trees to prevent damage
from glyphosate, either by compacting the
Arundo (manually pulling down and bending stalks before spraying) or by trimming
tree branches that extend into the Arundo.

and especially the emerging new stalks.

Figure 1. Dead Arundo clump treated
with imazapyr without damage to adjacent
mulefat bush (right) rooted in same area.
biomass can be reduced to mulch by a ﬂail
mower.
Imazapyr products named Habitat (for
aquatic use) and Stalker® are registered in
California, while Arsenal® is available in
other states but not California.
Advantages and Limitations of
Low-Volume Method
A primary advantage of the low-volume method is that herbicide spray can
be selectively placed on Arundo foliage, so
that adjacent non-target vegetation is not
contacted. The herbicide mixture need not
be applied to the full length of leafy Arundo
stalks or to all stalks in a discrete clump.
For example, beneath a tree canopy
invaded by Arundo, herbicide treatment is
restricted to the lower leaves of tall stalks

Third, using a backpack sprayer, the
low-volume foliar treatment method is so
quiet, fast and precise that wildlife biologists with regulatory agencies may allow
treatment of dispersed Arundo clumps in
riparian corridors during spring and summer months without requiring bird nesting
surveys.
A primary limitation of the low-volume
treatment is the impracticality of spraying
large Arundo stands. Although low-volume
foliar applications may be possible using
helicopters, for ground work the backpack
sprayer is the appropriate tool: power
pumps deliver ﬂuid at rates too high for the
light sprinkle or precision placement of the
low-volume application method. Using a
backpack sprayer with a jet stream nozzle,
the maximum size of treatable clumps is
about 40 ft across. Larger Arundo stands
should be foliar sprayed using high-volume
equipment, or tractor-mowed, allowed to
resprout, and then treated with herbicide.
Although not a limitation, applicators
should be aware that imazapyr is slow-acting compared to glyphosate, and that leaf
yellowing won’t be conspicuous until about
one month after treatment. Follow-up
spraying should be delayed until at least 6
months after the initial treatment or until

the following spring/summer growing season when new stalks may have sprouted.
Registration and Label Directions
In the late 1980’s, American Cyanamid
Co. introduced the Arsenal formulation
of imazapyr in other states, which became
widely employed for foliar
treatment of saltcedar; but
Arsenal was never registered
in California. Instead,
in 1999-2000 American
Cyanamid and its successor,
BASF Corporation, registered the Stalker formulation in California, which is
normally employed for cut
stump, tree injection, frill
or girdle, and basal bark
applications. Stalker has a
supplement label allowing
“low volume foliar application in California”, that
speciﬁes mixtures of 3-5%
concentration in water, intended for spot treatments
of individual plants rather
than broadcast applications.

(Isopropylamine salt of Imazapyr) as Arsenal
and Stalker, but without the emulsiﬁers in
Stalker that enhance mixing with basal oil.
For spraying the relatively sparse foliage
of saltcedar or tamarisk, Mike Carrigan of
BASF recommends full coverage of saltcedar
foliage using 1% concentration of Habitat

In soil, imazapyr residues are slowly
degraded by microbes, with a half-life of
85- 140 days depending on soil moisture
level, and other conditions. One year after
application, herbicide activity in soil should
be sub-lethal and should not curtail seed
germination and growth of new
plants. In any case, with the
low-volume application method,
most spray mix should remain
on the target foliage and very
little should reach the ground
surface.
In sunlit water, imazapyr is
degraded by photolysis, with a
half-life of 3 -5 days. According
to the Habitat label, livestock are
allowed to drink treated water;
but applications are prohibited
to ﬂowing water within a halfmile reach upstream of potable
water intakes.
Imazapyr has a reputation for having the potential to
transfer from roots of target trees
to non-target trees, but in our
experience root transfer doesn’t
seem evident from Arundo to
adjacent trees. Perhaps root
systems of Arundo and trees are
located at different depths or do
not intergrow for some other
reason (see Fig. 1).

For low-volume foliar
treatment of Arundo clumps
and resprouts using Stalker,
pest control advisor Bob
Brenton, the manufacturer’s
consultant in California
during 1999-2000, recommended and demonstrated
the following application
method:
1. Mix 5% Stalker in
water with 5% methylated
seed oil (to promote spreading and leaf penetration)
such as MSO Concentrate®
from UAP Timberland,
Can-Hance® from Monterey Chemical, or Hasten®
from Wilbur-Ellis.

Economic Considerations
Approximate costs per net
acre of Arundo control methods:
Foliar treatment without cutting

Figure 2 (top). Ammbusher rotary mower is effective at clearing Arundo
between closely spaced trees and on steep slopes. Figuew 3 (bottom).
Hydro Ax hammer-ﬂail mower cuts and mulches as much as 1 ac/day of
dense Arundo.

2. Apply spray mixture at rate of about
10 gal/ac, equivalent to a light sprinkle coating about 20% of the Arundo foliage surface
area.
In August 2005 BASF obtained California registration for Habitat herbicide for
control of emergent and ﬂoating aquatic
vegetation and terrestrial vegetation growing near surface water. Habitat contains
about the same amount of active ingredient

plus 1% surfactant; however the Habitat
label also permits the low-volume foliar
application method with 5% herbicide concentration plus spreader/penetrating oil.
Environmental Considerations
According to product literature, imazapyr has exceptionally low toxicity, carcinogenicity and mutagenicity to animal life.
The chemical affects biochemical processes
involved with protein synthesis that animals
and humans lack.

1) Low-volume application
of imazapyr to small clumps:
$1,000-$1,500/ac.

Restricted to clumps smaller than
40 ft across, treated by applicators using backpack sprayers;
assume 12 hours labor @ $60/hr
for initial treatment and 2-3 follow-up visits
over two years plus $250 for 3 quarts imazapyr herbicide and adjuvant.
2) High-volume application of glyphosate to
large stands: $3,000-$7,000/ac.
Suitable for Arundo stands as large as 1
acre, treated by 4-man crew using gasolinepowered pump, ladders and long hoses to
apply 60-100 gal dilute glyphosate herbicide
…continued page 11

Cal-IPC News Spring 2006

The Dose (and the Surfactant) Makes the Poison
Glyphosate formulations and amphibians
Two recent studies have addressed the
toxicity of glyphosate formulations to amphibians. In August 2005, Dr. Rick Relyea
of the University of Pittsburgh published
a study, entitled “The lethal impact of
Roundup on aquatic and terrestrial amphibians,” that has stirred discussion in the restoration community regarding herbicide use.
He found that glyphosate plus the surfactant POEA caused mortality to tadpoles and
juvenile frogs. Also in 2005, Joel Trumbo
of the California Department of Fish and
Game found few toxic effects to frogs
from glyphosate using R-11 surfactant. We
present summaries of each article and Joel
Trumbo’s analysis of their differences.

shown that POEA is the primary cause of
death to amphibians subjected to glyphosate plus POEA and he believed that it was
the cause of toxicity in his study as well,
although his methods could not separate the
effects of glyphosate from the surfactant.

lated Roundup products, Relyea’s results
were not at all surprising. It’s true that
Roundup (glyphosate plus surfactant) is at
least moderately toxic to aquatic organisms,
including ﬁsh and tadpoles. That’s why the
product is illegal to use in water.

Joel Trumbo applied Rodeo (the
formulation of glyphosate approved by the
EPA for aquatic environments) with R-11
surfactant directly to the surface of a pond
to simulate atypically high concentrations
in water, with the goal of determining the
concentration that would be lethal to 50%
of northern leopard frog (Rana pipiens)
tadpoles within 96 hours (referred to by

One of the most confusing things
about this topic is the tendency for people
to be incautious as to what chemical they’re
referring to. It is easy for people who
read Relyea’s article to interpret the terms
“glyphosate”, “Roundup”, and “formulated
glyphosate products” interchangeably.
Relyea points out that the surfactant in the
formulated glyphosate product Roundup
causes the toxicity. (That’s pretty common
knowledge for those of us in this ﬁeld).
Glyphosate itself has been proven to be
practically non-toxic for ﬁsh and tadpoles.
Still, people talk about “how toxic glyphosate is to frogs”. That’s a pretty signiﬁcant
error. It’s the surfactant in the Roundup
product, not the glyphosate, that is toxic.

The Two Studies
Herbicides are often applied in formulations that include a surfactant, which
helps the herbicide penetrate the surface of
the target plant. Surfactants can have more
signiﬁcant non-target impacts than the
active herbicidal ingredient on other oganisms, especially in aquatic habitats. Roundup® and Rodeo® are two brand names
for glyphosate formulations. Rodeo has no
surfactant and is designed and approved for
use near open water. Roundup uses surfactant and is not approved for aquatic use.
Dr. Relyea used ﬁeld and laboratory
experiments to test the effects of a commercial formulation of Roundup on leopard
frogs (Rana pipiens), American toads (Bufo
americanus), and gray tree frogs (Hyla versicolor) (Relyea 2005). In his ﬁrst experiment,
glyphosate with POEA (polyethoxylated
tallowmine) surfactant was applied as direct
overspray to ponds containing the three species of amphibian tadpoles, using a concentration typically used on upland areas. (This
simulated conditions that would occur with
negligent overspray or inadvertent treatment of ﬂooded depressions.) In his second
experiment, juvenile amphibians (those
that had undergone metamorphosis out of
the tadpole stage) were placed in laboratory
containers and subjected to the same direct
overspray conditions. In the ponds, 98%
of the tadpoles died within three weeks of
the overspray, while 78% of the juvenile
amphibians in the laboratory died in one
day. Relyea stated that previous studies have

Cal-IPC News Spring 2006

California red-legged frog.
Photo: CA Dept. of Fish and Game
toxicologists as the 96-hour LC50 value)
(Trumbo 2005). Leopard frogs were used
because they are closely related to the stateprotected California red-legged frog, Rana
aurora draytonii. His study failed to produce
dead tadpoles in toxicity tests that contained
high levels of both glyphosate and the R-11
surfactant. The hazard of the Rodeo/R-11
mixture to aquatic life was largely determined by the concentration of R-11 because
it is the more toxic compound in the tank
mix. Although glyphosate can be toxic at
levels in excess of 500 mg/L, R-11 can be
toxic at approximately 1-6 mg/L.
Analysis
by Joel Trumbo, California Department of
Fish and Game
My impression of Dr. Relyea’s article
was that it was well-written and accurate.
Given what we already know about the
aquatic toxicity of the surfactant in formu-

Relyea makes a couple of important
points: 1) the surfactant in the formulation, not the active ingredient glyphosate,
is toxic to tadpoles, and 2) the high levels
of amphibian mortality in his results were
the product of “direct overspray” to water.
I believe he means an accidental (and illegal) overspray to water that is of the same
magnitude as the intended application to
the terrestrial target. In other words, the
applicator didn’t try to avoid the water; the
water surface got the same dose as the land.
I think this type of overspray is not outside
of the realm of the real world. It does happen, but there can be a signiﬁcant difference between this type of “direct overspray”
and the lowered residues that might be the
product of drift. The difference between the
two scenarios (drift vs. direct overspray) becomes all the more critical depending on the
application method. Drift from an aircraft
is likely to be of a greater magnitude than
drift from a low-pressure backpack spray
delivered several inches above the terrestrial
weed target. Remember, the dose makes the
poison.
My study used the aquatically-approved
glyphosate product, Rodeo, but I did add
the surfactant R-11 to the tank mix. Add-

In Memoriam: Jan Lowrey
Jan Lowrey, past Executive Director of the
Cache Creek Conservancy in Woodland, died
on January 21, 2006, at the age of 57. He
was a longtime member of Cal-IPC and a
strong advocate for restoration work. He will
be missed. The following are just a few highlights from Jan’s work with the conservancy,
as described in the California Watershed
Network E-News.

an effort to tackle the tamarisk and Arundo
donax problem in the watershed, the Cache
Creek Conservancy, with grants from CALFED and Wildlife Conservation Board, removed and controlled these invasive species
along a 12-mile stretch of the creek. Jan was
instrumental in working with the USDA to
establish biological control of tamarisk using
leaf-feeding beetles.

With Jan’s lead, the Cache Creek
Conservancy restored an abandoned mine
pit in Yolo County into a ﬂourishing
wetland system. The 40-acre wetland site
is now a key component of the 130-acre
Cache Creek Nature Preserve. The preserve
includes restored wetlands, interpretive
kiosks, a “tending and gathering garden,”
nature trails, and observation platforms.

Jan solicited UC Davis graduate students and members of the Native American
community to develop the Tending and
Gathering Garden. This natural resource
gallery hosts plants native to the local watershed that have been used traditionally for
basketry, ﬁber, food, and medicine. Native
American cultural practitioners have access
to this secure resource for teaching, cultural
interpretation, and public outreach. The
garden is also used to examine traditional

Jan led numerous invasive species
removal projects along Cache Creek. In
ing the surfactant in to the tank mix pretty
much gets you back to a higher hazard situation used by Relyea for tadpoles because
R-11 is moderately toxic to aquatic fauna.
In that way, our studies are similar. Relyea’s
use of Roundup and my use of Rodeo +
R-11 present a moderately toxic scenario to
tadpoles. The question then becomes one of
exposure. In my study, we used high rates of
both Rodeo and R-11 in impounded water
with no aquatic vegetation. That means
any non-target ﬁsh or tadpoles would be
exposed to high chemical levels. It wasn’t a
typical scenario, but not outside the realm
of the possible or probable.
The main difference between the two
studies is likely the type and amount of surfactant. Relyea’s Roundup formulation contained the surfactant POEA; my experiment
used R-11, which contains the surfactant
NPE (nonphenyl polyethoxates). My study
failed to produce dead tadpoles in toxicity tests that contained high levels of both
glyphosate and the R-11 surfactant. My
application method was the same as Relyea’s
“direct overspray”. Since both surfactants
have similar tadpole toxicities (around 1-6
ppm), you have to assume that the difference between his study and mine would
then be the concentrations of the surfactants
that ended up in the water. Relyea mentions
glyphosate concentrations in his study, but

does not list POEA concentrations. It would
be interesting to know how much POEA
was in the water. My NPE concentrations
peaked on Day 0 at around 1ppm but were
down to 0.02 ppm by Day 4 (96 hrs., the
exposure time needed to produce 1-6 ppm
toxicity.)
In spite of the fact that I applied herbicide and added R-11 surfactant to the water
surface at high levels, the NPE concentration in the pond still wasn’t high enough
to produce tadpole mortality. Again, the
dose makes the poison. It’s not a question of
whether or not the NPE is toxic to tadpoles.
If you get enough in the water, you will kill
them. In the case of my study, direct spray
of high use rates still didn’t produce dead
tadpoles.
In summary, low volume/low pressure/
low drift applications of glyphosate and surfactant to terrestrial sites near frog habitat
should not be expected to produce tadpole
mortality. This is especially true if you use a
lower aquatic risk surfactant. There are several on the market. I don’t want to exaggerate the aquatic toxicity risk posed by R-11
(I feel it can be used safely near water), but
there are lower aquatic toxicity surfactants
on the market. Further, ground-based applications produce very little drift (backpack
sprayers produce almost none).

indigenous ﬁre management practices.
Jan also spearheaded a creative
and effective environmental education
program that offers an extremely diverse
and rewarding educational experience for
students grades K-12, as well as ﬁeld trips
for university level classes.
One of Jan’s talents was the ability to
build partnerships. As a fourth generation
farmer along Cache Creek, Jan could not
only “talk the talk” with local landowners,
but continuously impressed decision-makers at all levels, from county Boards of
Supervisors to state politicians. Assembly
Member Lois Wolk remembered Jan as
being “truly committed to open space and
agricultural preservation in Yolo County.”

Finally, you should give some thought
to whether tadpoles are actually present in
the water when you are making the applications. Most glyphosate applications to established perennial weeds should be done at or
near ﬂowering (late summer or early fall). I
think that most frogs should be in the adult
stage by then. If you go with the commonly
held thought that the tadpoles are the most
sensitive life stage, you can increase your
margin of safety by spraying when there are
no tadpoles.
For More Information
Relyea, R. A. 2005. The lethal impact of
Roundup on terrestrial and aquatic amphibians.
Ecological Applications. 15(4):1118-1124.
Trumbo, J. 2005. An assessment of the hazard
of a mixture of the herbicide Rodeo® and the
non-ionic surfactant R-11® to aquatic invertebrates and larval amphibians. California Fish and
Game. 91(1):38-46
US Environmental Protection Agency Pesticide
Information. www.epa.gov/pesticides
California Department of Pesticide Regulation.
www.cdpr.ca.gov
Rick Relyea’s webpage: www.pitt.edu/~relyea

Contact the author at jtrumbo@ospr.dfg.ca.gov

Cal-IPC News Spring 2006

Horticulture

Recommended Action on Invasive Ornamentals
The Cal-HIP (California Horticultural Invasives Prevention) Partnership, which brings
Cal-IPC, Sustainable Conservation, and The
Nature Conservancy together with representatives from the horticultural community,
is deciding on the steps necessary to remove
invasive plants from the nursery trade. The
following recommendations were submitted by
Cal-IPC for consideration by Cal-HIP partners in March. Some of the researchers listed
here collaborated with Cal-IPC on a proposal
submitted to the USDA National Research
Initiative in January to further research genetic
and distribution issues on these plants.
In its work to prevent the introduction
of invasive plants through horticulture in
California, Cal-HIP faces the need to act on
several high-proﬁle invasive plants with incomplete knowledge about precisely which
species or cultivars are—and are not—problematic. While further research has been
proposed to work on determining the
culprits with more accuracy and certainty,
the partnership may want to act before new
information is available. This set of recommendations, reviewed by top invasive plant
scientists in the state, provides potential
near-term actions that seem appropriate
based on existing knowledge.
Cortaderia selloana (pampasgrass),
C. jubata (jubatagrass)
Both plants are listed in the Cal-IPC
Invasive Plant Inventory with High ecological impact. C. jubata is listed as a Noxious
Weed by the California Department of Food

Jubatagrass in Richmond (Contra Costa
County). Photo by Bob Case.

Cal-IPC News Spring 2006

and Agriculture (CDFA), and is not thought
to be available in horticulture. It should not
be used in horticulture. C. selloana remains
available, including multiple cultivars. Existing research indicates that all cultivars of C.
selloana may contribute to the introduction
of invasive populations. Additional research
has been proposed to determine to what
extent genetic varieties and cultural practices
contribute to the likelihood that a given
planting can contribute to invasive populations. C. selloana infestations are found
in California coastal habitats, and more
recently in Central Valley riparian locations
and other habitats with adequate moisture,
typically near urbanized areas. The most
cautious approach would be to eliminate
the use of all C. selloana cultivars. This is
also the simplest approach, since distinction
between relatively safe cultivars and cultural
practices may be complicated.
Pennisetum setaceum (fountain grass)
Cal-IPC lists P. setaceum with Moderate ecological impact. Existing research
indicates that green varieties of P. setaceum
are invasive, while red varieties (P. setaceum
‘Rubrum’) are not. Additional research is
proposed to further delineate species behavior. Green varieties of P. setaceum seem most
aggressively invasive in southern California,
but have been reported in northern California. The appropriate action at this time is to
eliminate use of green P. setaceum only.
Hedera species

or at least those driving current invasions, it
may be most appropriate to wait for further
research before recommended the restriction
of any particular ivies. In the meantime, the
potential risks associated with ivies should
be presented, and responsible practices to
reduce possible spread should be promoted.
These include proper trimming to prevent
fruiting (and thus spread of seed by birds),
and proper disposal of potentially viable
vegetative matter.
Brooms
Many brooms are known to be invasive
in California and other Paciﬁc coast states,
including French broom (Genista monspessulana), Scotch broom (Cytisus scoparius),
Spanish broom (Spartium junceum), Portuguese broom (Cytisus striatus), and bridal
veil broom (Retama monosperma). Several
of these are listed as Noxious Weeds by
CDFA, and none should be used in horticulture. “Sweet broom” (C. spachianus or G.
racemosa) has not to date been found to be
invasive, but should not be recommended.
Reviewers
Dr. Carla Bossard, Biology Department,
St. Mary’s College of California
Dr. Joseph DiTomaso, Weed Science Program, University of California, Davis
Dr. Jodie Holt, Chair, Botany and Plant Sciences Department, UC Riverside
Dr. Marie Jasieniuk, Vegetable Crops Department, UC Davis

Invasive ivies are found statewide,
with the largest problems in riparian areas
and forest understories. Weed workers in
California think of Hedera helix and Hedera
canariensis as invasive (and Cal-IPC lists
them with High ecological impact), but to
date there is no detailed research into exactly
which species or cultivars are invasive in
California. Researchers in Washington
state using molecular analysis found that
certain cultivars (such as Hedera hibernica
and H. helix ‘Star’) were most problematic
there (Hedera canariensis is not present in
Washington). Similar research is proposed
for California to determine which cultivars
are most problematic here.

Connick, S., and M. Gerel. Don’t sell a pest:
A new partnership to prevent plant invasivions through horticulture. Cal-IPC News,
Summer 2005.

Because genetic testing may be able to
isolate a relative few problematic cultivars,

“Friends of the Partnership” online newsletter, www.suscon.org/invasives

Dr. Ingrid Parker, Biology Department,
UC Santa Cruz
Dr. Sarah Reichard, Conservation Biology,
University of Washington
Dr. Giles Waines, Botany and Plant Sciences
Department, UC Riverside
For More Information

This year’s California Invasive Weed Awareness Week is July 17-23.
Weeds Week is a chance for community groups around the state to
make their local citizens and policy makers aware of the problems
caused by invasive plants, as well as the important work done to protect
California’s native habitats.
We encourage you to organize an activity for Invasive Weeds Week:
hold a work day or an open house at a restoration project, design an
exhibit for a local event, invite your politicians and their staff for a tour
of projects, or write an article for a local paper. The Cal-IPC website has
a guide for developing Invasive Weeds Week activities, with how-to tips
for a variety of events.
The Cal-IPC website will also serve as a central location for posting
activities. Please send a short announcement of your event, including date, time, place and contact information, to Elizabeth Brusati
(edbrusati@cal-ipc.org). Afterward, let us know how many people
attended and send photos and a copy of any local press coverage. We
will compile a summary of events to help even more groups develop
activities in future years, and to show legislators at next year’s Day at
the Capitol that citizens across California are concerned about invasive
plants.
To obtain a copy of the poster at left, contact Katie Filippini
(kﬁlippini@cdfa.ca.gov) at the California Department of Food and
Agriculture.

Seeking Outreach Articles for Summer Newsletter
Two of the most challenging aspects of invasive plant work can be building community support for projects and providing information to diverse audiences. In the next issue of Cal-IPC News, we would like to showcase innovative outreach efforts related to invasive plants
or habitat restoration. Has your group developed creative outreach materials? Increased participation from the local community, including children? Overcome community suspicion about a controversial project? Tell your fellow weed workers about your successes and help
them learn from your mistakes. We are seeking short articles from a couple of paragraphs to a page of text in length. Photos are encouraged.
Please send submissions to Elizabeth Brusati, edbrusati@cal-ipc.org by June 30.

Arundo and Imazapyr, continued…
mixture; high end of price range includes
labor to compact Arundo and trim native
trees where intermixed.
Mechanical biomass reduction plus herbicide treatment
1) Large ﬂail mower followed by resprout
spraying: $4,000-$6,000/ac.
Suitable for dense stands larger than
one acre on relatively open, level terrain; assume $3000-5000/ac for biomass reduction
by ﬂail mower (Fig. 2) and $1000/ac for low
volume foliar treatment of resprouts using
imazapyr herbicide.

2) Small ﬂail or rotary mower followed by
resprout spraying: $7,000-$10,000/ac.

accessibility, amount of dead thatch, etc.

Suitable for steep slopes and stands intermixed with trees; assume $6000-$9000/
ac for biomass reduction by smaller ﬂail or
rotary mower (see Figure 3) and $1000/ac
for low volume foliar treatment of resprouts
using imazapyr.

Bob Brenton, Brenton VMS, 916-716-9822,
brenvms@comcast.net

For More Information

Mike Carrigan, BASF Corp., 970-674-9147,
carrigj@basf-corp.com
Contact the author at bgneill@earthlink.net

3) Chainsaw crew with portable shredder:
$20,000-$150,000/ac.
Suitable for locations requiring biomass
reduction but not accessible to mower tractors; price range depends on stand density,

Cal-IPC News Spring 2006

Horticulture

Cal-IPC Response to
“Border War”

Working with Landscape
Architects in San Diego

On March 19, The New York Times ran an op-ed piece by George
Ball, president of Burpee Seed Company and former president of
the American Horticultural Society, that was critical of attempts to
remove invasive ornamentals (voluntarily or by regulation) from
commercial trade. Cal-IPC and others responded to his piece with
letters to the editor. Here is Cal-IPC’s letter.

The San Diego Chapter of the American Society of the Landscape Architects and the San Diego Chapter of the California Native
Plant Society worked together to produce the San Diego County
Invasive Ornamental Plant Guide. This online guide was designed to
educate landscape professionals and the general public on invasive
plants and how to avoid their use in planted landscapes in the San
Diego region.

Dear Editor,

The Guide is especially important for landscape architects
working in the wildland-urban interface where urban development
borders natural plant communities. It is intended to be a reference
to landscape professionals as they choose plants for projects near
wildlands.

I read with interest the opinions of George Ball, former president of the American Horticultural Society, regarding “chauvinism against non-native plants” (“Border War,” March 19). Sadly,
Mr. Ball expresses a common misperception—that concern over
the extensive impacts of invasive plants on our natural areas and
economy requires a rejection of all non-native plants.
In California, about 200 plants are considered invasive, a
minute fraction of the non-native plants in the state. Invasive
plant management has nothing to do with rejecting valuable
crop or ornamental plants, xenophobia, or “elite snobbery.” Such
management is based on sound science and good public policy.
Fortunately, we have many willing partners in nursery and
landscape trade organizations who recognize the valuable role the
horticultural community plays in preventing the introduction
of invasive plants. We look forward to having current leadership
at the American Horticultural Society join us in this important
work.
Doug Johnson
Executive Director, California Invasive Plant Council

The Guide divides plants into two categories: Most Invasive and
Moderately Invasive. Most Invasive plants are those that spread to
wildlands even when they are not planted nearby. They are aggressive invaders and the Guide strongly discourages their use in the
landscape. Moderately Invasive plants have been documented in
wildlands and have the potential to spread into native plant communities from planted landscapes near natural areas. For these plants,
the Guide offers suggestions on evaluating whether a plant will be
invasive in a particular location.
For More Information:
American Society of Landscape Architects – San Diego Chapter
www.asla-sandiego.org/content/plantguide.html
California Native Plant Society – San Diego Chapter
www.cnpssd.org

New
and Contributing Members
Thank you for your generous support! This list reﬂects donors and new members since the last newsletter.
New Members
John Boland, Boland Ecological Services San Diego – Alasdair Coyne, Ojai
– Adrienne DeBissehop, Oakland – Mike
Dungan, TEC, Inc., Santa Barbara – Bob
Falconer, CA Association of Nurseries
and Garden Centers, Sacramento – Leora
Feeney, Alameda – Jeffrey Firestone, UC
Davis – Gary Halsey, Watershed Collaborative, Sacramento – Graciela Hinshaw, BLM, Folsom – John Holloway,
Sea Ranch – Deveree Kopp, US Forest
Service, Fawnskin – Amy Litton, Irvine
Open Space Preserve, Costa Mesa – Robert
McKee, Davis – Barbara Meislin, Tiburon
– Eddie Meyerholz, La Mesa – Regine
Miller, Downieville – Bruce Orr, Stillwater
Sciences, Berkeley – Randi Paris, NRCS,

Cal-IPC News Spring 2006

Yreka – Sharon Parker, Jensen Landscape,
Fremont – Marcel Rejmanek, UC Davis
– Cristina Schultz, CA State Parks, Avery – Lauren Singleton, Modesto – Harry
Spanglet, CA Dept. of Water Resources,
Sacramento – Nicholas Staddon, Monrovia
Growers, Azusa – Denise Stearer, USFWS,
Ojai – Jocelyn Torralba, Sant Clara Valley
Water District, San Jose – Chariss Tweedy,
Jones & Stokes, Fair Oaks – Jessie Vinje,
Cetner for Natural Lands Managment,
Escondido – Douglas Weihe, Chula Vista
– Frederick Wisor, Santa Rosa

Donations
Greg Archbald, Nevada City – Dan Gluesenkamp, San Francisco – Barbara Meislin,
Tiburon – Audrey Miller, Ferndale – Kelly

Rose, Playa Del Rey – Jake Sigg, San
Francisco

Donations for Cape Ivy Biocontrol
[Cal-IPC sends 100% of these donations
to USDA-ARS to support South African
research partners.]
P. Van Aggelen, San Francisco – California
Native Plant Society (CNPS) Los Angeles/Santa Monica Mountains Chapter
CNPS Monterey Chapter CNPS Orange
County Chapter – CNPS San Diego
Chapter – CNPS Santa Clara Valley
Chapter – Jean Conner, San Francisco – El
Cerrito Garden Club, El Cerrito – Lawrence Janeway, Chico – Rio Piedras Club,
Carmel – Swimmer Family Foundation,
Los Angeles – Susan Wilde, San Francisco

Horticulture

“Bay-Friendly” Program Integrates
Non-Invasive Landscaping with Waste Reduction
by Cynthia Havstad, StopWaste.Org
Cal-IPC is a partner in the Bay Friendly
Program, an innovative local project aimed at
promoting sustainable landscaping. The program provides an excellent avenue for educting
ghe public about invasive plants.
Sustainable landscaping is gaining
support nationwide, because of its multiple
beneﬁts to the environment and the community. In Alameda County, StopWaste.
Org, aka the Alameda County Waste
Mangement Authority, considers sustainable
landscaping an essential means of reducing
the tons of plant debris that are landﬁlled
every year, while building markets for compost and mulch.
StopWaste.Org launched the BayFriendly Landscaping and Gardening program, reaching out to residents, landscape
professionals and local public agencies with
a broad array of educational materials, including printed guidelines, trainings, model
public policy, technical assistance, grants,
and awards. The goal is to encourage broad
participation in Bay-friendly landscaping in
Alameda County and the greater Bay Area.
Bay-Friendly Landscaping and Gardening offers a holistic approach that recognizes
that one component of reducing waste from
the landscape is plant choice and placement. Reducing plant debris is also about
watering practices, fertilizing practices, and
building soils with compost for vibrant,
disease resistant plants that don’t need to be
replaced before they’ve reached their natural
life expectancy.
With this integrated approach comes
the opportunity to collaborate with other
agencies and organizations that have similar,
sometimes intersecting missions, messages,
and audiences, such as Cal-IPC. Although
the Bay-Friendly program focuses primarily
on the built landscape, we recommend that
plant species that are invasive to the San
Francisco Bay area be avoided in order to
minimize future plant debris while protecting our local ecosystem.
Towards this end, the Bay-Friendly
Landscaping Guidelines: Sustainable
Practices for the Landscape Professional

and the Bay-Friendly Gardening Guide
for Homeowners include Cal-IPC’s list of
Invasive Garden Plants of the Greater San
Francisco Bay Area and their recommended
alternatives. StopWaste.Org’s Bay-Friendly
programs have distributed more than 3,000
of Cal-IPC’s “Don’t Plant a Pest!” brochures.
The Bay-Friendly Gardening Program
is partnering with Cal-IPC, local nurseries,
Alameda County Countywide Clean Water
Program and East Bay Municipal Utility
District to:
1. Educate more residents at point-ofsale about selecting appropriate plants and
other Bay-Friendly practices.
2. Provide a resource for beginner
gardeners so that they can avoid invasives as
well as plants that require heavy water use.
3. Develop relationships with nurseries,
and in the future the growers and wholesalers who provide the plants, and educate
their staff about the Bay-Friendly Program.
The collaboration has generated a list of
California native and Mediterranean species
that are conserve water, thrive in Bay-Area
microclimates, grow fairly easily, and are
relatively disease resistant. The plants are
identiﬁed as Bay-Friendly Plants in the nurseries with our pelican logo and are stocked
at ﬁve nurseries in Berkeley, Fremont, San
Leandro and Oakland.
Civic landscape projects can also access
technical assistance and grants from StopWaste.Org. The recommendation to avoid
invasive plant species becomes a requirement if an Alameda County public agency
receives a Bay-Friendly Landscape grant to
build or renovate a public use landscape.
Existing Bay-Friendly landscape projects, including a new ﬁre station in Pleasanton and
renovated street medians in Albany, were
presented to 125 professional landscape
designers and public agency decision makers
in March. Both projects met the requirement that the planting plans not specify
invasive plant species.
As a part of our comprehensive approach we also encourage our 14 member

cities in
Alameda
County
to adopt Bay-Friendly
Landscaping policies for both civic
and private sector projects. In civic projects
the model policy recommends that all new
public landscapes meet a minimum of 60
points on the “Bay-Friendly Landscaping
Plan Review and Scorecard”. By adopting
these model policies, Cities are also adopting the Bay-Friendly practice to not plant
invasive plant species. For private sector
projects, the policy recommends adopting
Bay-Friendly Landscape Guidelines as an
ofﬁcial city document, encouraging (but not
requiring) private landscape projects that
qualify for planning commission review to
use the Bay-Friendly Landscape Guidelines
and Score Card for their projects. This
voluntary approach is seen as the best ﬁrst
step for introducing these practices to the
private sector.
Primary to our agency goals, BayFriendly Landscape and Gardening recommends that invasive weed debris be kept
out of the landﬁll to the maximum extent
possible. Invasive plant species often are
pervasive and difﬁcult to compost in such a
manner as to prevent re-infestation. Placing
invasive plant debris in the green carts for
municipal collection and composting is
often a better option than trying to compost it in a backyard compost pile. We also
recommend The Weed Worker’s Handbook,
from The Watershed Project and Cal-IPC
which details appropriate disposal methods
for 27 Bay Area invasive weeds, balancing
the goals of reducing waste and preventing
their spread.
In your pursuit of minimizing the
impacts of invasive plants, we invite you to
participate in this broader approach and to
use the Bay-Friendly Landscape Guidelines
and materials as a resource.
For copies of the Bay-Friendly Landscape Guidelines, model policies, scorecard,
resources for residents or to ﬁnd out about
other tools, visit www.StopWaste.org.

Cal-IPC News Spring 2006

Readings &
Resources
Grassland Newsletter: Jeff Corbin, a
graduate student at UC Berkeley, produces
the online CA Grassland Newlsetter, with
research summaries, job announcements,
and a variety of other grass-related info.
cbc.berkeley.edu/grass
Video: The National Forest System released
the ﬁrst video of a series on best management practices for invasive species prevention. “Dangerous Travelers – Controlling
Invasive Plants along America’s Roadways”
is a 26-min. program that targets road maintenance personnel and equipment operators.
The initial production run is available on
DVD or via the internet free of charge.
www.fs.fed.us/invasivespecies/news.shtml
Historic Photos: 3100 US Forest Service
photos from vegetation surveys in the
1920s and ‘30s are available through the
UC Berkeley Library. They are part of the
Wieslander Vegetation Type Map Survey,
which covered national forests in California, Oregon, and Nevada. Photos can
be searched by USGS quad, location, key
word, or species.
www.lib.berkeley.edu/BIOS/vtm
Ivy Video: A video and DVD on English
ivy have been produced by Leif Joslyn,

Seen a new resource your fellow weed workers
should know about?
Please contact edbrusati@cal-ipc.org.
who previously produced videos on yellow
starthistle, pampasgrass, and brooms.
Contents include “What is a weed?”, urban
and wildland impacts, other views, identiﬁcation and life cycle, and threat to the coast
redwood ecosystem. The video or DVD can
be purchased for $25. www.xenob.com

New Book: In summer 2006, Montana
State University Extension will release
Inventory and Survey Methods for Nonindigenous Plant Species, a 180-page guide
that “demystiﬁes mapping terminology
and presents information on choosing and
designing the most appropriate method
for a particular management area.” www.
weedcenter.org

NOW AVAILABLE FROM CAL-IPC

Position Paper: The Ecological Society of
America has produced a position paper entitled Biological Invasions: Recommendations for U.S. Policy and Management. It
evaluates U.S. national policies and practices
on biological invasions in light of current
scientiﬁc knowledge and makes six recommendations for future actions. ESA released
the paper was released during National
Invasive Weeds Awareness Week in February
and distributed it to Congressional ofﬁces,
committees, and federal agencies.
www.esa.org/pao/esaPositions
Military Report: The National Wildlife
Federation produced a report in October
2005 entitled “Under Siege: Invasive Species on Military Bases” that describes the
costs and damages that the Defense Department has incurred from invasive species,
including examples from several bases in
California. www.afpmb.org/bulletin/vol25/
under_siege.pdf or www.nwf.org

The Use of Fire as a
Tool for Controlling
Invasive Plants
By Joseph DiTomaso, Matt Brooks,
Edith Allen, and Ralph Minnich
49 pp., color photographs
This report is the result of a workshop
organized by Cal-IPC and sponsored by
the Center for Invasive Plant
Management, USGS, and the Joint Fire
Science Program.
Chapters include:
~ Planning and Implementing
Prescribed Burns
~ Control of Invasive Plants with
Prescribed Fire
~ Using Prescribed Fire in Integrated
Strategies
~ Effects of Fire on Plant Communities
~ Effects of Fire on Chemical, Physical,
and Biotic Properties of Soil

Cytisus scoparius on former ponderosa pine area. Images from the Wieslander Vegetation Type Mapping Collection are courtesy of the Marian Koshland Bioscience and Natural Resources Library, University
of California, Berkeley, www.lib.berkeley.edu/BIOS/vtm/.

Cal-IPC News Spring 2006

First pringin is Free, plus $5 shipping &
handling. Call Cal-IPC at (510) 8433902, or order from our website.

The WILDLAND WEED CALENDAR
Know of an event that should be posted here?
Please contact edbrusati@cal-ipc.org.
California Mapping Coalition Conference
Week of May 15 (date TBA)
University of California – Davis
Call Cal-IPC at (510) 843-3902 for details.
Cal-IPC Wildland Weed Field Course:
Management Techniques
May 24-25
Cache Creek Conservancy, Woodland, CA
An expanded two-day version of the course
taught at the Chico Symposium. Includes
an exercise in designing a management
program. $250 Cal-IPC members / $270
non-members. www.cal-ipc.org

Using California Native Grasses in the
Urban Landscape

North American Weed Management
Association

June 2
Oakland, CA
This workshop by the California Native
Grasslands Association presents uses of
California native grasses in urban landscaping projects.
www.cnga.org

September 18-21
Calgary, Alberta, Canada
www.nawma.org

Society for Conservation Biology:
Conservation Without Borders
June 24-28
San Jose, CA

Weeds Across Borders

This meeting aims “to transcend real and
perceived boundaries of ecology, sociology,
politics, and human behavior that impede
conservation science and its application.”
www.conbio.org/2006

May 25-28
Hermosillo, Sonora, Mexico

Conference on Biological Control

The 3rd Weeds Across Borders Conference
sponsored by the Federal Highway Administration and the Arizona-Sonora Desert
Museum. Share information with scientists, practitioners, and policy makers from
Canada and Mexico.
www.desertmuseum.org/borderweeds
borderweeds@desertmuseum.org

July 25-27
Riverside, CA

Bay Area Open Space Council

Topics are importance of biological control
to the citrus industry, history of the Agricultural Experiment Station, risk assessment
for weed biological control, and ongoing
biological control research for the urban
environment.
www.cnr.berkeley.edu/biocon/CCBC%20V.
htm

June 2
San Francisco, CA

Ecological Society of America

The theme of this year’s annual conference
is Building Whole Communities, honoring
connections between people and land.
OpenSpaceCouncil.org

Memphis, TN
August 6-11
www.esa.org

Quotable
“Y
ellow Star Thistle… When botanists
“Iwen thewillend,
ﬁrst made known its presence in Califorconserve only what we love
nia it could have been exterminated for
less than a hundred dollars; at the present
time, millions of dollars would not sufﬁce.”
Jepson’s A High School Flora for California (1935). Contributed by Roy West.

we will love only what we understand
we will understand only what we are
taught.”

Meeting the Challenge: Invasive Plants in
Paciﬁc Northwest Ecosystems
University of Washington
September 19-20
Seattle, WA
The conference goal is to create strategies and partnerships to understand and
manage plant invasions in the Paciﬁc
Northwest. Contact Timothy B. Harrington,
tharrington@fs.fed.us or 360-753-7674.
15th Australian Weeds Conference:
Managing Weeds in a Changing Climate
September 24-28
Adelaide, South Australia
www.plevin.com.au/15AWC2006
Cal-IPC Pre-Symposium Field Course:
Tools for Early Detection Programs
October 4
Audubon Canyon Ranch’s Bouverie
Preserve, Glen Ellen
www.cal-ipc.org

15th Annual Cal-IPC Symposium
Research and Management: Bridging the
Gap
October 5-7
Rohnert Park, CA
www.cal-ipc.org

Tamarisk Research Conference
Current Status and Future Directions
October 3-4, 2006
Fort Collins, Colorado
A meeting devoted to tamarisk ecology and
management.
www.tamarisk.colostate.edu

Baba Dioum, Senegalese Scholar. Contributed by Carri Pirosko.

Cal-IPC News Spring 2006

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 that includes scientists, land managers, policy makers, and concerned citizens.
Please complete this form and mail with check or credit card number. Additional donations support our projects. We are a 501(c)(3) nonproﬁt organization, and donations beyond regular membership rates are tax deductible. Join or donate online at www.cal-ipc.org.
2006 Individual Membership
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$75
Life
$1,000
Joint Cal-IPC/SERCAL
$55
Joint Cal-IPC/CNGA
$70
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Student/Volunteer
$15

2006 Institutional Membership
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$150
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Name
or nonproﬁt
$100
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