CalEPPC
News
A quarterly
publication
of the California
Exotic Pest Plant Council
Volume 6 Number 4
Fall 1998
IN THIS ISSUE
Presidents Message
by Mike Pitcairn ……………….. p. 3
Results of CalEPPC
Questionnaire
by Joe DiTomaso …………….
CalWeed Database
by Steve Schoenig ……………
p. 4
p. 6
Invasive New Zealand Weeds
p. 8
by Graham Harris ……………
Volunteer displays rooted Arundo donax washed onshore during El Niño storms.
See page 5 for article. Photo by Annette Shears
Symposium on Invasive
Weeds at WSS
by Jodie Holt ………………….
p. 8
CalEPPC News
Who We Are
CalEPPC NEWS is published quarterly
by the California Exotic Pest Plant
Council, a non-profit organization. The
objects of the organization are to:
j provide a focus for issues and
concerns regarding exotic pest
plants in California;
j facilitate communication and the
exchange of information regarding
all aspects of exotic pest plant
control and management;
j provide a forum where all interested
parties may participate in meetings
and share in the benefits from the
information generated by this
council;
j promote public understanding
regarding exotic pest plants and
their control;
j serve as an advisory council regarding funding, research, management
and control of exotic pest plants;
j facilitate action campaigns to
monitor and control exotic pest
plants in California; and
j review incipient and potential pest
plant management problems and
activities and provide relevant
information to interested parties.
1999 CalEPPC Officers and
Board Members
Officers
President
Vice-president
Secretary
Treasurer
Past-president
Mike Pitcairn
Joe DiTomaso
Anne Knox
Sally Davis
Ann Howald
At-large Board Members
Greg Archbald
Joe Balciunas
Carla Bossard
Tom Dudley*
Mike Kelly
Jo Kitz*
John Randall
Steve Schoenig*
Ellie Wagner*
Peter Warner*
email;
email:
email:
email:
email:
email:
email:
email:
email:
email:
email:
email:
email:
email:
email:
*Board Members whose terms expire December 31, 1999
Working Group Chairpersons
Arundo
Artichoke thistle
Brooms
Cape ivy
Cortaderia spp.
Euphorbia
Fennel
Lepidium
Saltcedar
Spartina spp.
Spurge
Veldtrass
Volunteers
Yellow starthistle
Nelroy Jackson
Mike Kelly
Karen Haubensak
Greg Archbald
Joe DiTomaso
Jo Kitz
Jennifer Erskin
Joel Trumbo
Bill Neill
Steve Jones
Jo Kitz
Dave Chipping
Pete Halloran
Mike Pitcairn
909.279.7787
619.566.6489
510.643.5430
415.561.3034,ex.3425
530.754.8715
818.346.9675
530.753.8193
916.355.0128
714.779.2099
510.803.7011
818.346.9675
805.528.0914
415.647.5300
916.262.2049
nejack@monsanto.com
mkellysd@aol.com
Editor
Sally Davis
32912 Calle del Tesoro, San Juan Capistrano, CA 92675
ph. 949.487.5473 email: sallydavis@aol.com
karenh@socrates.berkeley.edu
greg_archbald@ggnpa.org
jmditomaso@ucdavis.edu
mtnsrt@aol.com
jaerskine@ucdavis.edu
jtrumbo@hg.dfg.ca.gov
bneill@unocal.com
jonessteve@worldnet.att.net
mtnsrt@aol.com
dchippin@calpoly.com
peteholloran@igc.org
mpitcairn@cdfa.ca.gov
CalEPPCs web site: http://www.caleppc.org
Submission Dates for CalEPPC News
If you would like to submit a news item, an article, a meeting announcement, or job opportunity for publication in the CalEPPC News, they must be received by the deadlines listed
below. Editor reserves the right to edit all submissions. Send your text/disk/email
to editors address above.
Submission Dates:
Spring
Summer
Please Note:
The California Exotic Pest Plant Council is a
California 501(c)3 non-profit, public benefit
corporation organized to provide a focus for issues
and concerns regarding exotic pest plants in
California, and is recognized under federal and state
tax laws as a qualified donee for tax deducible
charitable contributions.
Page 2
Fall 1998
April 15
July 15
Fall
Winter
October 15
January 15
The articles contained herein were contributed to the CalEPPC newsletter.
These articles represent the opinions of the authors and do not necessarily
reflect the views of CalEPPC. Although herbicide recommendations may
have been reviewed in contributed articles, CalEPPC does not guarantee
their accuracy with regard to efficiancy, safety, or legality.
CalEPPC News
Presidents Message
Mike Pitcairn
C
alEPPCs Symposium 98 is
over. It was held October 2-4 at
the Ontario Airport Sheraton Hotel
in Ontario in southern California
and, I must say, it was another
excellent symposium. The speakers
were interesting, stimulating, and
inspiring, and the field trips were
educational and focused.
This years meeting highlighted
two important aspects of exotic
weed removal: working safely,
whether with hand equipment or
applying herbicides, and working
together through volunteer crews.
All speakers are to be congratulated
on their excellent presentations.
This symposium could not have happened without the work of several
individuals. Carl Bell, Brenda
Ouwerkerk, Jo Kitz, Nelroy Jackson, and Pete Holloran made up the
Program Committee. Thank you for
arranging this years outstanding
speakers.
Nelroy Jackson and Sally Davis
arranged for use of the hotel, Saturdays banquet luncheon, and made
sure the necessary audio/visual
equipment, refreshments, etc., were
provided when needed. Thanks to
both of you. Barbara Leitner organized the poster session again this
year. Thank you for a job well done.
Christine Berry and Matt Brooks
led the full-day field trip and Paul
Frandsen, Nelroy Jackson, and
Jennifer Nocera led the half-day
field trip. Thanks to all of you for
your efforts.
I attended the full-day field trip
which was excellent, and I heard
only positive comments regarding
the half-day trip. The full-day trip
focused on the impact of alien
grasses invading the Mojave Desert.
Their primary impact is the introduction of ground fires into areas
where fire historically had not been
present. Usually, there are large
areas of bare ground among the
native vegetation in the desert, but
following the invasion of alien
grasses these bare areas are covered
with a carpet of short grasses. When
dry in mid-summer, the grasses carry
low ground fires throughout an area.
Few of the native desert flora, such
as Joshua trees, yucca, and creosote
Few of the native
desert flora, such
as Joshua trees,
yucca, and creosote bushes, can
survive these low
ground fires …
bushes, can survive these fires. The
grasses readily re-invade the burned
areas and after a second fire, little
native vegetation remains.
Matt and Christine showed us
areas of the desert that have had no
fires, one fire within the last ten
years, and two fires within the last
ten years. The change in flora from
mixed native vegetation to almost all
grasses was astounding and scary.
Not surprisingly, this change in
vegetation impacts the native fauna
as well, in particular the desert
tortoise. Christine gave an interesting presentation on desert tortoise
biology and the current research
that is being performed. I encourage
anyone who has not been on one of
CalEPPCs field trips to attend one
next year.
Next years symposium is
planned for the Sacramento area
and efforts to organize it are already
underway. I hope you are planning
to attend. j
Letter to
the Editor
T
wo years ago, I was asked to fill
a position on the CalEPPC
Board of Directors for a mid-term
vacancy. I knew I didnt have time
to take on this additional time
commitment and…heaven forbid…
additional work. Nevertheless, I
enthusiastically said YES! Two years
later, as I leave the board, due to
new career priorities, I wish I could
once again say YES, and more! The
experience of working with the
CalEPPC Board and members is one
I would gladly commit time to.
Id like to thank each of the
CalEPPC board members and
officers for the fantastic, interesting,
worthwhile two-year experience. I
felt my limited time was never
wasted, and I learned so much about
exotic pest plants and people! I also
made some friends that I will never
forget.
Id like to encourage each
CalEPPC member to consider
participating in CalEPPC beyond just
the annual Symposium or working
groups. The strength of CalEPPC is
the leadership of the board, and the
diversity and passionate commitment
of our members toward the prevention, discovery, and control of exotic
pest plants. Through individuals
willing to say YES, CalEPPC has
gained a highly respected leadership
reputation throughout California, the
United States, and the world.
I am very proud to be a part of
this organization, and am glad I said
YES!
Brenda W. Ouwerkerk
Fall 1998
Page 3
CalEPPC News
Results of the CalEPPC Questionnaire at
Symposium 98 in Ontario
by Joe DiTomaso
Many thanks to those who took the time to complete the questionnaire at the CalEPPC
Symposium held in Ontario. There were 46 completed surveys. The following is a
summary of the tabulated results:
What are your major invasive weed problems?
Of the 66 species listed by those responding to the survey, only the top 27 species are listed below. These represent
species (or plant groups) reported to be invasive by at least 5% of those responding.
Yellow starthistle (50%); Eucalyptus spp. (22%); purple starthistle (11%); annual grasses (48%); brome grasses (21%);
gorse (9%); other thistles (44%); ice plant (20%);Vinca spp. (9%); Arundo donax (39%); Brassica spp. (17%);
red brome (9%); Cortaderia spp. (39%); tocalote (13%); tree tobacco (9%); saltcedar (37%); Ailanthus altissima (13%);
poison hemlock (7%); brooms (33%); perennial pepperweed (13%); Acacia spp. (7%); Cape ivy (30%); castor bean
(11%); Himalaya blackberry (7%); fennel (22%); Ammophila sp. (11%); Spartina sp. (7%).
What are your major job responsibilities?
Most people indicated more than one area of responsibility. Of those responding, 80% were involved in fieldwork,
48% in administration, 37% in public education, 11% in research, and 7% in academic education. Other categories
were also listed but represented less that 5%.
Are you employed by a:
60% by public agencies, 13% by private companies, 11% by non-profit organizations, 9% were concerned citizens
not employed to manage invasive weeds, 6% were associated with academic institutions, and 2% employed by
homeowner associations.
In what areas do you primarily work?
Riparian ecosystems (65%); roadsides (33%); coastal dunes (4%); coastal wildlands (48%); forests (30%);
industrial sites (2%); wetlands (48%); prairie (grasslands) (28%); recreational areas (2%); rangeland (37%); marine
aquatic (9%); turf/landscapes (2%); foothill wildlands (33%); utility areas (9%); development sites (2%); freshwater
aquatic (33%); desert (7%); alluvial fan scrub (2%).
What control methods do you use for managing invasive weeds?
After thousands of years, hand-pulling still remains the most commonly used method of weed control.
Hand-pulling (76%); reseeding (30%); insect biocontrol (11%); cut stump herbicide (63%); intensive grazing (24%);
rope wick herbicides (7%); broadcast herbicide (50%); picks, shovel, loppers, chainsaw, machete (20%); basal spray
herbicides (7%); mowing (46%); weed whipping (15%); irrigation (4%); prescribed burning (43%); tillage (15%); spot
spray herbicides 4%); weed wrench (39%); rotational grazing (13%); herbicide injection (2%); hack and squirt (30%);
heavy equipment, e.g. dozers, brush rake, backhoe, ripping (11%).
Do you supervise volunteers in your weed management efforts?
Yes (56%); no (44%)
If yes, what type of volunteers do you supervise?
General public (79%); school children (44%); members of environmental or conservation organizations (76%);
prisoners (40%); youth groups (56%).
Do you directly use herbicides or supervise those who do?
80% of the total responses either directly supervised, used or both supervised and used herbicides. Directly use
(11%); supervise use (16%); both (52%); neither (20%).
Page 4
Fall 1998
CalEPPC News
Survey (contd)
How frequently do you use herbicide (growing season)?
Of those indicating that they use herbicides 24% use them once to a couple of times a year, 29% use them about
once a month, and 47% use them once a week or more.
Which herbicides do you use for invasive weed control?
A number of products were mentioned. To simplify this, the list is organized by the active ingredient. For example,
both Rodeo and Roundup contain glyphosate, the active ingredient. Garlon, Remedy, Brush-B-Gon, and Path
finder contain triclopyr. Glyphosate was used by everyone who indicated that they used herbicides.
Glyphosate (100%); Sethoxydim (6%); MSMA (3%); Triclopyr (69%); Fluazifop (6%); Oryzalin (3%); Clopyralid
(20%); Chlorsulfuron (3%); Oxadiazon (3%); 2,4-D (11%); Imazapyr (3%); Dicamba (9%); Diuron (3%).
Do you use integrated weed management strategies?
Yes (73%); No (27%)
Are you a licensed or certified applicator?
Yes (39%); No (61%)
In your weed control efforts, do you include site restoration?
Yes (62%); No (38%)
If yes, briefly indicate what type of restoration effort you implement.
Of the 23 responding that they included site restoration, most replanted with native species. The techniques used
included hydroseeding, planting container plants, drill seeding perennial grass seed, plug planting, broadcast
seeding, pole planting. Others encouraged recovery of existing native seed banks.
What area of the state does your job responsibilities cover?
Of those attending the symposium in Ontario, approximately 44% had job responsibilities within Southern California, 28% in Central California, 21% in the Bay Area or Northern California, and 7% in the Sierra Nevada.
Following is a more specific breakdown: Southern California (20%); San Diego (7%); North Coast (5%); Central
Coast (20%); Central Valley (7%); Northern Valley (2%); So. Calif. Desert (11%); Sierra Nevada (7%); Northern
California (2%); Bay Area (11%); Los Angeles (5%); Entire state (2%). j
The Weed from Hell Arrives in Paradise
by Frank Starkey, Catalina Island Conservancy
L
iving on Santa Catalina Island,
we are accustomed to welcoming non-natives which show up on
our shores. They are usually arrive
via a ferry and stay for a brief time in
one of the hotels in Avalon. This
past spring we had a vast number of
unwelcome non-natives rafting to
the islands beaches and coves,
staying and taking root. The spring
storms had washed Arundo donax
from mainland river channels and
then out to sea. Thousands, literally
tons, of the Weed from Hell
floated across the twenty-six mile
channel and washed ashore onto our
paradise.
Once here, even after soaking in
salt water for several weeks, a
number of the rhizomes still had the
tenacity to take root and send out
vigorous new sprouts. Knowing the
well-earned reputation of Arundo
wreaking havoc on native plants and
habitat, the Catalina Island Conservancy mobilized staff and volunteers
to hit the beaches, searching for and
removing this new threat. Six
months after the initial episode we
still encounter new sprouts in areas
in which we had previously removed
plants.
We are hopeful that the early
removal efforts and follow-up monitoring will prevent this unwelcome
non-native from getting a foothold in
our island paradise. j
Fall 1998
Page 5
CalEPPC News
Access Weed Control Information
Through the CalWeed Database
by Steve Schoenig, California Department of Food and Agriculture
T
he CalWeed database, offering
information on weed control
projects throughout California, is up
and running. CalWeed is an
Internet-based searchable database
containing information about
noxious weed control projects
within the state. The project began
as a subcommittee effort of the
California Interagency Noxious
Weed Coordinating Committee
(CINWCC). Led by staff of the
California Department of Food and
Agriculture, the inventory of
projects has received additional
funding from the Bureau of Land
Managements California office.
The Committee hopes that the
database will serve as a useful tool
to agency staff, researchers, biologists, and the public by facilitating
the exchange of weed control
information. Above all, it should
serve as a networking tool for staff
with weed control and land management responsibilities.
An agreement with the University of Californias Information
Center for the Environment (ICE)
has allowed CalWeed to reside
under the larger umbrella of the
Natural Resource Projects Inventory
(NRPI), another Internet-based
database. The NRPI structure allows
the weed control project information to be available through either
its own Web site, specific just to
weeds, or under a more general
Web site which will access project
descriptions for all resource management work being reported in
California.
CalWeed provides viewers with
short reports on various weed
control efforts. Information available
for a specific project includes:
project title, purpose, and
abstract
weed targeted for control
project contact
cooperators, funders, and
landowners
general location and
habitat information
control methods used
A visitor to the site can view a
complete list of CalWeeds projects,
or can refine a search by county,
targeted weed, or control method.
More search categories will be
available in the future. Also in the
future, CalWeed will contain an
online encyclopedia of noxious
weeds.
CDFA has contracted with Dr.
Joe DiTomaso and his staff at the
University of California, Davis to
provide viewers with specific information about both weed biology and
control methods.
CalWeed currently contains
reports on over 350 projects and is
continually updated with new arrivals. If you have a project that you
would like to report, simply fill out
our three-page dataform and send it
in. Forms may be accessed from the
CalWeed home page, or by contacting Steve Schoenig at 1220 N
Street, Room A-357, Sacramento,
CA 95814, 916.654.0768,
sschoenig@cdfa.ca.gov.
Visit CalWeed at:
http://endeavor.des.ucdavis.edu/weeds/
Page 6
Fall 1998
What
Constitutes
a CalWeed
Project?
Projects which qualify for this
database attempt to eradicate or
reduce the number of noxious
weeds in California. The emphasis of CalWeed is on weeds
deemed noxious by the California
department of Food and Agriculture, or considered a threat to
wildlands by the California Exotic
Pest Plant Council.
The focus of the database is
on projects that target specific
weeds for control. These can be
weeds that threaten natural areas,
rangelands, open spaces, or
agriculture. There is less interest
in non-specific vegetation management or biomass abatement.
Weed control for urban landscapes and intensive production
agriculture is also not emphasized
in CalWeed.
Projects should be in an active
or maintenance phase; historical
projects are currently outside the
scope of our efforts. j
CalEPPC News
More on Salsola soda
by Peter Baye, U.S. Fish & Wildlife Service, Mare Island Suboffice
T
hanks to Judi Tamasi for her
attention to Salsola soda, an
estuarine marsh invader which needs
more attention than it has been
getting. I have a few comments and
observations to update the information available.
Salsola soda is well established
in northern San Pablo Bay, where it
has some of the most extensive
populations anywhere in the estuary.
The Mare Island dredge disposal
ponds, saline basins of dredged muds
which are annually drained and
disced, support several hundred
acres of weedy halophyte habitat in
which S. soda is common to dominant. It also is co-dominant on many
tens of acres of adjacent salt marsh
where alluvial fans had previously
formed from spilled or discharged
dredge slurry. S. soda also is abundant on the levees surrounding the
dredge ponds, particularly in tire ruts
and disturbed soil. It also has invaded
drift-lines (tidal litter deposits) in high
salt marsh in adjacent tidal wetlands,
and is locally abundant in brackish
marshes with artificially reduced tidal
action. S. soda also appears in
conspicuous local abundance on
side-cast excavated bay muds where
ditches are excavated in the tidal salt
marsh along Highway 37 to improve
tidal circulation, particularly east of
Sonoma Creek. It has made initial
invasions in recently restored tidal
marshes, such as the Sonoma Land
Trust Petaluma Marsh Restoration
Project (Carls Marsh immediately
north of the Petaluma River bridge at
its mouth).
The abundance of S. soda near
the mouth of the Napa River and
Carquinez straits is of particular
concern, because this places it well
within dispersal range of the endan-
gered soft birds-beak (Cordylanthus
mollis ssp. mollis). Both species are
most abundant in the high marsh
zone where soils are relatively better
drained and less frequently inundated. In the tidal brackish marshes
of the north bay, this zone is also
the preferred habitat for perennial
pepperweed (Lepidium latifolium)
… a double threat to birds-beak
habitat.
Salsola soda is also becoming
widespread in undisturbed salt
marsh vegetation in parts of the
south Bay. In Dumbarton Marsh and
Newark Slough (one of the largest
salt marsh areas in the south bay)
Salsola soda is now invading not
only the typical high tide drift-lines
and disturbed levees, but also
common to locally abundant on tidal
creek bank edges (often with
Atriplex triangularis and Grindelia
stricta) and on extensive areas of
outer Dumbarton Marsh in undisturbed, dense mixed stands of
Distichlis spicata and Salicornia
viarginica.
S. soda is abundant also on the
oyster shell berms that form on
eroding marsh edges around
Ravenswood, Bair Island, Bird
Island, and Greco Island. These
unstable narrow beach ridges were
the probably former habitat of the
endangered California sea-blite
(Suaeda californica), now extirpated in San Francisco Bay, but
planned for reintroduction. Heavy
invasion by S. soda in this rare subhabitat could interfere with reestablishment of Suaeda. Similarly,
if Salsola becomes abundant on
natural creek bank levees, it could
interfere with reintroduction and
reestablishment of two other historic
salt marsh species which are extir-
pated in the south bay, an owls
clover (salt tolerant populations of
Castilleja ambigua ssp. ambigua)
and Point Reyes birds beak
(Cordylanthus maritimus ssp.
palustris). These species have an
affinity for areas of sparse, low, or
disturbed salt marsh vegetation which
Salsola really colonizes and monopolizes.
Regarding the unfilled niche
concept, S. soda seems to behave
this way on novel, artificial habitats
which are periodically disturbed, such
as levees and dredge disposal ponds.
Atriplex triangularis, a native
annual Chenopod, seems to at least
partially overlap with S. sodas actual
ecological niche in San Francisco
baylands. However, I have little doubt
the seed rain of S. soda generated by
these artificial habitats poses an
unacceptably high potential invasion
rate in important habitats such as salt
pans at marsh edges, and in high
marsh vegetation supporting rare or
endangered species. j
Fall 1998
Page 7
CalEPPC News
Invasive New Zealand Weeds: Our
Native Plant Invaders
by Graham Harris, Natural Resources Centre, Open Polytechnic,
New Zealand
M
ost New Zealanders are well
aware of the damage that
introduced invasive plants such as
gorse, broom, old mans beard,
blackberry and many others have
done to New Zealands landscape leaving a legacy that costs the
country millions of dollars annually.
Few New Zealanders are likely to be
aware that some of our native plants
have created similar problems
overseas. Graham Harris, a lecturer
in the Natural Resources Centre at
the Open Polytechnic, looks at some
of our plants that have invaded the
landscapes of other countries.
While numerous species and
cultivated varieties of our native
plants have been exported overseas
where their beauty and many unique
features are appreciated, a few,
finding an environment where their
natural competitors are missing and
the climate and the habitat are to
their liking, have become invasive.
They have dominated local plants
and damaged ecosystems by growing
faster and reproducing more quickly
than in their natural environment.
Some of these plants have been
labeled with classifications such as
alien invasive weeds, noxious weeds,
and exotic pest plants of concern.
To put this into perspective
however, while about 2000 exotic
plants have become established in
the wild in New Zealand and more
than 200 of these are classified as
weeds which are placing many of
our native species under threat, only
a few of our native plants have
become invasive overseas and in
only a handful of countries. California, in the United States, is one of
Page 8
Fall 1998
the places where some of our plants
have created problems. However as
one Californian authority noted, In
general , New Zealand plants behave
themselves in California – not like
those from South Africa and
Eurasia, and a scientist from the
University of California commented,
The majority of invasive weeds in
California are from Eurasia and
North Africa (about 65%) while
California, in the
United States, is
one of the places
where some of our
plants have created
problems.
relatively few (about 5%) are from
Australia and New Zealand. Other
places where New Zealand plants
have become invasive include the
islands of Hawaii, the south Atlantic
islands of St. Helena and Tristan da
Cunha, and the southwestern tip of
South Africa.
Some New Zealand plants that
have created problems overseas
include karaka (Corynocarpus
laevigatus) which is a serious weed
pest in Hawaii where it is described
as an aggressive colonizer that forms
a dense shade which excludes other
species, including some endangered
native plants. Karaka was planted in
the Hawaiian islands over 100 years
ago. In 1929 it was further spread
for reforestation purposes by broadcasting seeds from aircraft over the
interior of the island of Kauai. It is
now present on four islands with
major infestations on the islands of
Kokee and Kauai. Seeds are being
further spread by birds and there are
serious concerns that infestations
will spread to other islands. Of
particular concern is the threat that
the karaka poses to the heau
(Exocarpus luteolus), a member of
the sandalwood family and one of
Hawaiis most endangered plants. A
programme to monitor and control
the karaka has been initiated by
Hawaiian authorities.
Harakeke or New Zealand flax
(Phormium tenax) was an important
source of fibre for Maori which later
formed the basis of a large fibre
industry providing local and export
markets with rope, fabric and other
fibre products. At the turn of the
century, New Zealand flax was
planted in several countries to
establish similar fibre industries. In
the south Atlantic island of St.
Helena, well known as the place
where Napoleon died in exile in
1821, flax was widely planted. The
economy of the island was totally
dependant on flax fibre when the
industry collapsed in the 1960s.
New Zealand flax has had a serious
impact on the islands ecosystem
which includes a unique flora of 49
plants found nowhere else in the
world. A paper published by the
University of Hawaii noted, Although the prehistoric flora of St.
Helena is poorly known, one-third of
the known endemic flora is extinct
and no vestiges of former ecosystems remain. New Zealand flax is the
most serious pest. A programme to
eradicate flax from the island has
CalEPPC News
New Zealand (Contd)
been implemented. New Zealand flax
is also an invasive weed on the south
Atlantic islands of Tristan da Cunha
where the British authorities have set
up a programme to monitor its
spread. In Hawaii, New Zealand flax
was cultivated prior to 1871 and is
now classed as an alien invasive pest
plant. On two of the islands it has
formed dense thickets which exclude
other plants.
Ngaio (Myoporum laetum) is
regarded as a serious invasive weed
in southern Californias coastal areas
and it has also spread south into the
Baja California peninsular in Mexico.
In California it is described as a most
invasive wildland pest plant and it is
listed on the California noxious
weeds list. It forms dense single
species thickets that expand each
year and outcompete other plants.
Birds spread the seeds, greatly
enlarging the affected areas.
Programmes to control the plant in
California are underway.
Pohutukawa (Metrosideros
excelsa) has been planted as an
ornamental in the Western Cape
province of South Africa for many
years and large mature trees can be
seen in the gardens of Cape Town
and other towns of the province. In
recent years the pohutukawa, along
with many other introduced invasive
plants, has begun to invade sections
of the nearby fynbos – a delicate
ecosystem of 71,000 square kilometers, renowned for its huge range of
native plant species. The fine seed of
the pohutukawa which is produced
in vast quantities, is spread by wind.
Some areas in the fynbos provide
ideal conditions for germination and
growth of the plant. The dense
masses of seedlings that are developing and becoming established indicate the likelihood that impenetrable
stands of trees which suppress native
flora will develop. While no official
programme to control the
pohutukawa has been initiated as
yet, concerned locals have already
begun to remove the plants.
Manuka (Leptospermum
scoparium) and kanuka (Kunzea
ericioides) were first planted in
Hawaii about 70 years ago and they
have now infested several islands
where they form thickets which
crowd out and suppress other
plants. While they are classed as an
alien invasive pest plant they have
provided some benefits by stabilizing
ridge tops that have eroded following overgrazing by goats.
Ti kouka or New Zealand
cabbage tree (Cordyline australis)
has infested Salt Point State Park in
northern California where its
growth is encouraged by the cool
foggy coastal conditions. It is listed
by the California Exotic Pest Plant
Council as a wildland weed which
needs more information. The
council is keeping the plants under
close observation because of the
potential for the seeds to be distributed more widely by birds.
Kokihi or New Zealand spinach
(Tetragonia tetragonioides) is a
listed noxious weed in several states
in the U.S. As the plant is also
endemic to Asia, Australia and parts
of the South Pacific, New Zealand is
not necessarily the source of the
initial introduction.
Piripiri or bidibidi (Acaena
tetragonioides) is an invasive weed
in California and several other states
in the US and is listed as a U.S.
noxious weed. Taupata (Coprosma
repens) is listed as an exotic weed in
California although at present it is
not thought to be a threat to wildland habitats. Taupata is also considered to be a problem in some
coastal areas in Australia although it
is not officially classified there as
In recent years
the pohutukawa
has begun to
invade sections
of the nearby
fynbos…
being an invasive weed.
Houhere or lacebark (Hoheria
populnea) which is considered to be
a potentially invasive weed in California, became troublesome in the
Strybing Arboretum in San Francisco. Most of the mature trees were
removed and the seedlings are being
kept under control. Californian
authorities noted that fortunately the
plant is not available in the landscape trade and has not been widely
planted.
Poroporo (Solanum laciniatum)
and karo (Pittosporum crassifolium)
are considered to be weeds in cultivation in California. They are being
kept under observation to ensure
they dont escape into the wild.
All of the above plants, with the
exception of Acaena and
Tetragonia, were introduced intentionally, either as ornamentals or for
commercial purposes, to the places
where they have become invasive.
Those that have escaped into the
wild have reproduced rapidly, spread
their seeds widely and formed
thickets which have excluded nearly
all other plants. In the process they
have damaged natural areas, altered
ecosystems and displaced local
native species. However, our native
plants have only played a small part
in the global problem of invasive
species – an issue that has been
identified by the World Conservation
Union as a key global environmental
issue for the 21st century. j
Fall 1998
Page 9
CalEPPC News
Symposium on Invasive Weeds
by Jodie Holt, UC Riverside
A
special symposium on invasive weeds, Ecology and Control of Invasive Exotic Weeds: A National and
Regional Perspective, will be held during the annual meeting of the Weed Science Society of America in San
Diego, California, Feb. 7-10, 1999 at the Town and Country Hotel in Hotel Circle. The Invasive Weeds Symposium
will take place Feb. 8 from 1:00 p.m. to 5:00 p.m. in the San Diego Ballroom followed by a reception in the same
room. CalEPPC is co-sponsoring the symposium and has made special arrangements for CalEPPC members to be
admitted to the Invasive Weeds Symposium only for $10 (preregistration for the entire annual meeting is $125). Use
the coupon below to be admitted to the half day weed symposium or visit the WSSA Homepage at http://
ext.agn.uiuc.edu/wssa/ to preregister for the entire meeting. The program will be available on the Homepage in
November.
Abbreviated symposium program: Keynote Speaker, Senior Official from the Dept. of the Interior: National
Strategies for Invasive Exotic Weeds; Barry A. Meyers-Rice, The Nature Conservancy: Impacts of Invasive Weeds
on Natural Areas and What We Need to Know to Address Them; Sarah H. Reichard, Univ. of Washington: Traits
of Invasive Species and Their Predictive Ability; Michael G. Barbour, Univ. of Calif., Davis: California Landscapes
Before the Invaders; Joseph M. DiTomaso, Univ. of Calif., Davis: Invasive Weeds in Rangelands, Species, Impacts,
and Management; Nelroy E. Jackson, Monsanto Co.: Invasive Weeds in Riparian, Estuarine and Wetland Habitats,
Species and Impacts; Greg Jubinsky, FL Dept. of Environmental Protection and FL Exotic Pest Plant Council, Tallahassee: Invasive Weeds in Florida and the Southern United States, Species, Impacts, and Management Strategies.
Invasive Weeds Tour
Join the Symposium organizers and Mike Kelly, President of the Friends of Los Peñasquitos Canyon Preserve, for
a tour of the Los Peñasquitos Lagoon at the Torrey Pines State Reserve. The Reserve offers some of the most spectacular views of any park in California, including sandstone cliffs overlooking the Pacific Ocean. Weeds present in the
Reserve include giant reed (Arundo donax), iceplant (Carpobrotus edulis), veldtgrass (Ehrharta calycina), curly dock
(Rumex spp.), pampasgrass (Cortaderia jubata), saltcedar (Tamarix ramosissima), fennel (Foeniculum vulgare), and
catalpa (Catalpa spp.). The Reserve also faces invasion by native fresh-water species such as willow (Salix spp.) and
cattail (Typha spp.) into salt-water marshes. The tour will depart the Town and Country Hotel by bus Tuesday, February 9 at 8:30 a.m. and return by noon. To pre-register for the tour, send $15 by January 8, 1999 to cover the cost of
transportation to: Jodie S. Holt, Botany and Plant Sciences Dept., Univ. of Calif., Riverside, CA 92521, phone:
909.787.3801, fax: 909.787.4437, email: jodie.holt@ucr.edu.
INVASIVE WEEDS SYMPOSIUM CALEPPC MEMBER DISCOUNT COUPON
Sponsored by the WEED SCIENCE SOCIETY OF AMERICA and CalEPPC
February 8, 1999, 1:00 – 5:00 p.m. followed by a reception at the San Diego Ballroom of the Town and Country
Hotel, Hotel Circle, San Diego, California.
Present this coupon at the registration desk and be admitted to the Symposium for $10
Name____________________________________________________________________________________________
Address___________________________________________________________________________________________
__________________________________________________________________________________________________
Telephone_____________________
Page 10
Fall 1998
fax_____________________
Email_____________________
CalEPPC News
CalEPPC New Members
CalEPPC would like to welcome the following individual and institutional members
who have joined CalEPPC in the months from August through November 1998:
Patrick Akers
Ileene Anderson
Jon Avery
Kristin Berry
Jan Beyers
Mark Biloki
Jack Bramkamp
David Bramlet
Angelika Brinkmann-Busi
Laura Bube
Erick Burres
Dewayne Butler
Bobbie Calli
Anthony Cario
Ray Carruthers
Susan Carter
Tony Chappelle
Joe Decruyenaere
Bruce Delgado
Mark Depoy
Curt Deuser
Edward Dibella
Deborah Dorsett
Jennifer Erskine
John Gaskin
Daniel Gibbs
Suzanne Goode
Miriam Graham
Julie Greene
Darcy Guttilla
Ahmad Hashemi
Virginia Havel
Evelyn Healy
Scott Hennessy
Bonnie Hoffman
Kathleen Holt
Doris Hoover
Melissa Howe
Sandy Ivey
Mike Jaquith
Sarah Kimball
Jamie King
Janet Klein
Eddy Konno
Joe Lara
Sandy Leatherman
Zach Likins
Laurie Litman
Robert MacAller
Beth Merrill
Dez Mikkelsen
Jud Monroe
Barbar Moritsch
Rocky Moss
Emily Newby
Susan ONeil
Ben Oshum
Reneé Pasquinelli
Katherine Patey
Bruce Pavlik
Robert Pierce
Martin Rasnick
Mary Reents
Dina Robertson
Ray Sanchez
Allison Sanger
Tamara Sasaki
Gerry Scheid
Robert Schlipf
Richard Shefferson
John Shippen
Frances Shropshire
Ron Slimm
Holly Smit
Dale Steele
Scott Stenquist
Kristiaan Stuart
Gerald Taylor
Harold Thomas
Ian Torrence
Reijo & Ulla Ulmonen
Robin Wall
Ginger White
Richard Zembal
CalEPPC SYMPOSIUM 98 INSTITUTIONAL SPONSORS
PATRON
California Native Plant Society
CONTRIBUTING
Wilbur-Ellis Company
REGULAR
Agri Chemical & Supply, Inc.
Brewer International
CA State Parks OHMVR Div./Sac.
Circuit Rider Productions, Inc.
City of Palm Desert
City of San Diego Parks & Rec.
Elizabeth Crispin
Tom Dodson & Associates
Golden Gate Natl Parks Assoc.
Huntington Library
Lilburn Corporation
Arthur Morley
Natures Image, Inc.
Pestmaster Services/Bishop
Quail Botanical Gardens
Redwood National Park
Riverside Co. Regional Parks &
Open Space District
Sapphos Environmental
Smith & Reynolds Erosion
Control, Inc.
Target Specialty Products
Tree of Life Nursery
University of California Genetic
Resources Conservation
Program
US Fish & Wildlife Service/
Honolulu
Zuckerman Building Company
Fall 1998
Page 11
1999 CalEPPC Membership Form
If you would like to join CalEPPC, please remit your calendar dues using the form provided below. All members will
receive the CalEPPC newsletter, be eligible to join CalEPPC working groups, be invited to the annual symposium and
participate in selecting future board members. Your personal involvement and financial support are the key to success.
Additional contributions by present members are welcomed!
Status
Individual
Institutional
Name
q Retired/Student*
$20.00
N/A
Affiliation
q Regular
$30.00
$100.00
Address
q Contributing
$50.00
$250.00
q Sustaining/Patron $250.00
$1000.00
q Lifetime
N/A
$1000.00
Please make your check payable to CalEPPC and
mail with this application form to:
City/State/Zip
Office Phone
Home Phone
Fax
email
CalEPPC Membership
c/o
Sally Davis
32912 Calle del Tesoro
San Juan Capistrano, CA 92675-4227
* Students, please include current registration and/or class schedule
Calendar of Events
January 11 – 13
51st Annual California Weed Science Society Meetings, Anaheim. Contact: Wanda
Graves, 510.790.1252
January 11 – 15
Natural Resources Communication Workshop, Chico, sponsored by the Western Section
of the Wildlife Society. Contact: Dr. Jon K. Hooper, 530.898.5811 or 6408,
jhooper@facultypo.csuchico.edu
January 20 – 23
The Wildlife Society Western Section Annual Conference, Monterey, sponsored by the
Wildlife Society Western Section. Contact; William Hull, 510.465.4962, whull@cgbd.org
February 8 – 10
Weed Science Society of America Annual Meeting, San Diego. Contact: J. Breithaupt,
913.843.1235, jbeith@allenpress.com
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EXOTIC
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San Juan Capistrano, CA 92675-4427
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