CalEPPC
News
A quarterly
publication
of the California
Exotic Pest Plant Council

Volume 5 Number 2

Spring 1997

IN THIS ISSUE
Presidents Message
by Ann Howald ………. p. 3
Pampas Grass RFP ….. p. 4
Natural Areas Conference
in Portland …………….. p. 6
Rx for Applying
Herbicide to Tamarisk
by Bill Neill ……………. p. 7
Call for Nominations . p. 11
Calendar of Events … p. 11

Volunteers and National Park Service staff remove tamarisk from Burro Spring at the east
end of Lake Mead National Recreation Area.
Photo by Bill Neill.

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;

Officers

1997 CalEPPC Officers and
Board Members

President

Ann Howald

Vice-president

Mike Kelly

Secretary

John Randall

Treasurer

Mike Pitcairn

Past-president

Carla Bossard

Board Members whose terms expire December 31, 1997
Editor

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

Sally Davis

31872 Joshua Dr., No. 25D, Trabuco Canyon, CA
92679; 714.888.8541; email: sallydavis@aol.com
Nelroy Jackson
400 So. Ramona Ave., #212H, Corona, CA 91719;
909.279.7787;
email: nejack@ccmail.monsanto.com
Jo Kitz
6223 Lubao Ave., Woodland Hills, CA 91367;
818.346.9675; email: mtnsrt@aol.com
Jeff Lovich
USGS Biological Resources Div., 63500 Garnet
Ave., No. Palm Springs, CA 2258;619.251.4823;
email: jeffrey_lovich@nbs.gov
Brenda Ouwerkerk SLO County Dept. of Agriculture, 2156 Sierra Way,
Suite A, San Luis Obispo, CA 93401; 805.781.5910

Board Members whose terms expire December 31, 1998
Greg Archbald

j review incipient and potential pest
plant management problems and
activities and provide relevant
information to interested parties.

Joe Balciunas
Carl Bell
Joe DiTomaso
Steve Harris

Working Group Chairpersons

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 a qualified donee for tax deducible
charitable contributions.

Page 2 Spring 1997

210 Chestnut Ave., Sonoma, CA 95476;
707.939.0775; email:
102062.170@compuserve.com
11875 River Rim Rd., San Diego, CA 92126;
619.566.6489; email: mkellysd@aol.com
TNC Wildland Weeds Mgmt., UC Section of Plant
Biology, Davis, CA 95616; 916.754.8890; email:
jarandall@ucdavis.edu
CDFA, 3288 Meadowview Road,
Sacramento, CA 95832; 916.262.2049;
email:mpitcairn@smpt1.dfa.ca.gov
St. Marys College, Dept. of Biology, P.O. Box 4507,
Moraga, CA 94575; 916.758.1602; email:
egbossard@aol.com

Database
Membership
Nursery growers/landscape
architects liaison
Slide Collection
Species Mgmnt & Control:
Arundo
Brooms
German ivy/hoary cress
Lepidium
Pampas grass
Yellow starthistle
Tamarisk

GGNPA, Fort Mason, Bldg. 201, San Francisco, CA
94123; 415.673.4067, Ext. 25;
email: greg_archbald@ggnpa.org
USDA Biocontrol, 800 Buchanan St., Albany, CA
94710; 510.559.5975; email: joebalci@pw.usda.gov
UC Coop Ext., 1050 E. Holton Rd., Holtville, CA
92250; 619.352.9474; email: cebell@ucdavis.edu
UC Weed Science Prog., 210 Robbins Hall, Davis,
CA 95616; 916.754.8715; email:
ditomaso@vegmail.ucdavis.edu
P.O. Box 341, Arcata, CA 95518-0341;
707.443.6943; email: sharris@igc.org
Steve Harris
Sally Davis

707.826.2709
714.888.8541

Dan Songster
Tony Bomkamp

714.895.8161
714.837.0404

Nelroy Jackson
Carla Bossard
Dave Chipping
and Greg Archbald
Joel Trumbo
Quentin Griffiths
Mike Pitcairn
Bill Neill
and Jeff Lovich

909.279.7787
916.758.1602
805.528.0362
415.673.4067, Ext.25
916.355.0128
510.235.6501
916.262.2049
281.287.5246
619.251.4823

CalEPPCs web site: http://www.igc.apc.org/ceppc/index.html

CalEPPC News

Presidents Message
Ann Howald, President

S

pring is the season for broom
to bloom. Its abundant yellow
flowers make us aware of just
how far the shrub we love to hate
has spread. Recently I saw it bordering the oak and pine woodlands of
rural Lake County — places it wasnt
found a mere ten years ago. Driving
beyond what I thought was the last
outpost of broom on a winding road
that passes through serpentine
outcrops, I spotted an outlier several
miles beyond the nearest infestation.
Since it was public land, I did my
duty, restoring the landscape to its
pre-broom condition and, hopefully,
retarding the spread of one of
Californias Most Unwanted
Weeds. Oh, that it could be that
simple elsewhere.
From the number of new initiatives
to fight exotic pest plants in California, it appears theres been a sea of
change in our fight to rid our wildlands of exotic pest plants. So far,
the tide hasnt turned against most
of these invaders, but at least we are
on the crest of a wave, for the
moment. One of these new initiatives focuses on Pampas grass, that
silvery-plumed invader from South
America. As you will note, this issue
of CalEPPC news includes a Request
for Proposals for Pampas grass
projects which target eradication,
research and education. A benefactor who wishes to remain anonymous will provide project funding for
the next three years.
The Bureau of Land Management is
providing another important new
funding opportunity. Their War on

Weeds grant initiative will provide
funding for cooperative, innovative
projects with high visibility. Especially favored will be projects that
provide opportunity for public
education and involvement. (Deadline for the BLM War on Weeds
proposals was May 1st.)

..theres been
a sea of change
in our fight
to rid our wildlands
of exotic pest
plants.
Speaking of cooperation, a new
group has formed to fight Arundo in
northern California. Calling themselves Team Arundo del Norte, a
group of federal, state and local
agencies has teamed with researchers and non-profit groups like the
Sonoma Ecology Center and
CalEPPC to investigate the Arundo
problem up north. Well hear about
their work at CalEPPC Symposium
97 in Concord, October 10-12. On
the public education front, Bob
Devine, author of the 1994 Sierra
magazine article Botanical Barbarians which featured some of
Californias worst weeds and best
weed warriors, is writing a book on
exotic pest invasions that will showcase several of Californias most
infamous invaders.

As of April, CalEPPCs Board of
Directors has a new member. I am
very pleased to report that Brenda
Ouwerkerk, Deputy Agricultural
Commissioner for San Luis Obispo
County, has agreed to join our
Board of Directors. A vacancy was
created when Stella Humphries
resigned from the board due to her
relocation to the East Coast. We
thank Stella for all her help and wish
her the best in her new endeavors.
And we extend a warm welcome to
Brenda!
Lastly, I am very saddened to relay
news of the death of our friend and
colleague, Dr. Charles Turner.
Charlie was a scientist at the USDA
Albany biological control facility and
a member of CalEPPCs Board from
1995 to 1996. He was diagnosed
with cancer in late December, 1996,
and died in Indianapolis, Indiana, on
April 15, 1997. He will be greatly
missed by all who knew him.

Spring 1997 Page 3

CalEPPC News

Pampas Grass/Jubata Grass
Biology and Control

Request for Proposals from the California Exotic Pest Plant Council
Proposals Due September 5, 1997

T

he California Exotic Pest
Plant Council (CalEPPC) is
requesting proposals from
qualified public and private individuals or groups to provide educational
information, investigate the biology
and ecology, and develop innovative
management practices or pilot
studies for the control of weedy
Pampas grass (Cortaderia selloana)
and jubata grass (C. jubata), herein
collectively referred to as Pampas
grass. Funds supporting this request
have been provided by an anonymous outside donor with focused
interest in weedy Cortaderia species.

district staff, land managers, UC
Farm Advisors or IPM specialists,
and pest control advisors.

The priority areas of this program
are to: 1) provide broad education to
the nursery industry and the public
on the invasive qualities and detrimental effects of Pampas grass in
natural ecosystems, 2) provide a
better understanding of the invasive
characteristics, both biological and
ecological, of Pampas grass in
coastal environments, 3) develop
innovative sustainable control and
prevention strategies for Pampas
grass, and 4) demonstrate, through
a pilot project, a successful, economical, and environmentally safe
strategy for managing Pampas grass
along the California coastline.
Collaborative efforts are encouraged, but are not essential for
obtaining funding.

Process for Proposal Selection
Proposals will be reviewed by a
selected panel of CalEPPC members. Members of the panel will not
be eligible to receive funding. The
panel will use the following criteria
to evaluate proposals:

Who May Apply
Principal investigators may come
from public or private institutions
and may include state, federal, and
university researchers and educators,
as well as resource conservation
Page 4 Spring 1997

Funds
Funds may be used for personnel,
equipment, travel, supplies, and
expenses. Awards will range from
approximately $5,000 to $30,000
per year. Funding is for up to three
years. For multi-year proposals (up
to three years will be considered),
continued funding will be subject to
review from preceding years
progress report. Funding of grants is
contingent upon qualified proposals.

1. Does the project address one of
the priority areas for funding? For
continuing projects, how well did the
project meet the stated objectives
for the first or second year?
2. For educational grants, will the
proposed project reach the appropriate target audience? What will be
the potential impact of the educational program?
3. Does the project take a systems
approach to weed management
practice(s)? Does it also include
restoration processes?
4. Does the project address issues
of reduced-risk pest management?
5. Are the proposed objectives
realistic, economical, and effective

and is the work plan appropriate
and technically sound? Are the
investigators capable of carrying out
the project?
6. What is the likelihood that the
information developed will be
implemented or be useful in the
development of Pampas grass
management strategies?
Proposal Contents
1. Title page (no page number),
including:
a. Title of project
b. Name, address, organizational,
institutional or corporate affiliations
of the applicant(s). Include telephone
and facsimile numbers and, if applicable, E-mail addresses.
c. Budget total for each year of
the proposed work
d. Expected duration
2. A summary of the proposed
project not to exceed 250 words.
Include as a separate page with no
page number.
3. This section (begin with page 1)
is not to exceed six double-spaced
pages and includes:
a. Objectives of the proposal in
outline form.
b. Justification and Rationale.
Describe the importance of the
proposed work to Pampas grass
management or education. Discuss
previous work or experience in this
area. If applicable, provide any data
already collected on this proposed
project.
c. Work plans and methods.
Refer to each objective and explain
how the desired goals will be
achieved. For educational projects,

CalEPPC News

Pampas Grass RFP
(contd)

Ten Ways of Looking at Star Thistle

indicate details for each step of the
process. For research projects,
specify experimental design, sampling techniques, data to be collected, and data analysis. For pilot
control projects, describe in detail
the procedures to be employed.
d. Communication/Outreach or
Technology Transfer. Explain how
the results of this project will be
disseminated and how other groups
might adopt some of the practices
developed.
e. Describe the role of each
investigator and major collaborator
involved in the project. Include
names, affiliations, and expected
contributions of each individual.
f. Timetable. Present a timetable
for each stated objective.

I. The noon heat is oppressive. Across the road the cool river. Between us,
like a vast impenetrable desert, lies a stand of Star Thistle.

4. Budget (page 7). List expenditures per year for up to three years
of potential funding for the project.
Include the following categories:
Personnel (include title, job description, percent time, salary, and
benefits), supplies and expenses,
equipment, travel, information/
outreach costs, overhead or indirect
costs, and other relevant expenses.
Indirect costs cannot exceed 10% of
total funds requested.

VI. In the distance, the once golden hills of California are now covered
with Star Thistlea sea of the strangest hue, a pale grayish, greenish,
yellowish…what is that color?

5. Bibliography and cited tables,
figures, illustrations, or photos.
Proposal Submission
Seven copies (double-sided) of the
proposal must be delivered no later
than 5 p.m. on September 5, 1997.
Awardees will be notified by midOctober. Funds will be made available by November 1, 1997.
Proposals should be sent to:

Anonymous

II. Yellow Star Thistle originally came from Europe, hardened on the Old
World abuses; in the heat of increasing aridity, it now survives on our own
misuses. It first emerged on the dry foothills of the Adriatic; now it thrives on
the dry slopes of the Pacific.
III. This thorny barnyard bully, this street-wise opportunist; this arrogant,
offensive pestnothing but a rose with an attitude.
IV. The Greek gods, it is rumored, used the honey in their ambrosiaso
sweet and clear is its nectar, and more nutritious than clover, the nymphs
believed.
V. Botanically, Yellow Star Thistle is named Centaurea solstitialis, after the
centaurs, those Greek monsters, part man and part horse, famous in their
use of herbs. About 500 Old World species belong to this same genus,
including knapweed and other thistles.

VII. My master has left me to this barren field. No feed but this prickly weed.
The vultures circle, sensing my desperation.
VIII.The grasses have all departed; Star Thistle is on the move.
IX. In the final analysis, Star Thistle is natures ultimate weapon. A protector
of the land, carpenter for earthen ghettos, barnacle of the soil, it clings
tenaciously to its poverty, growing thick and impenetrable with age, offending all pedestrians, till ultimately a carpet of gray humus covers the land
preparing a bed for the great return of the grasses.
X. I was going to bale that hay today. But it is loaded with Star Thistle. I
guess Ill watch the game instead.
Ridgewalker

Dr. John Randall
TNC Weed Program
Department of Vegetable Crops
210 Robbins Hall
Davis, CA 95616
Spring 1997 Page 5

CalEPPC News

24th Annual Natural Areas Conference
and Exotic Pest Plant Council Conference
(Pacific NW, California, Florida, Tennessee Councils)

Doubletree Hotel and Conference Center
Portland, Oregon August 27-30, 1997

(formerly Red Lion)

Bridging Natural and Social Landscapes
Come to the first Natural Areas/EPPC conference ever held in the Pacific Northwest!

T

his conference is designed around the theme of Bridging Natural and Social
Landscapes. Linkages between natural and cultural/economic values of landscapes
will be explored through scientific presentations and informative discussions. We plan to
reassess the role of all kinds of natural areas in todays society and examine the role they
may play in the future. The conference will include symposia, contributed papers, poster
sessions, field trips, social events, and business meetings.

Audience

Anyone interested in natural area management including land managers, research
scientists, resource and stewardship specialists, cultural specialists, and students is
welcome.

Topics and Speakers

You will have an outstanding opportunity to hear international, national and
regional leaders in natural area management, avail yourself of the latest research
and technical information in the field, and exchange ideas with your colleagues.

Original Artwork by Margaret Herring

A

half-day symposium entitled Exotics in the Landscape will be offered in additional to the general session on
exotic plant species in natural areas. Conference organizers expect that additional papers addressing exotic species will be
presented in other symposia and general sessions. A good turnout is expected from EPPC members on the west coast, in
addition to attendance by members of the Florida EPPC and Tennessee EPPC. This conference will be a great opportunity for
NAA and EPPC members to formally and informally discuss shared issues and challenges while broadening their professional
network. Join us!

Symposia

New and Increasing Uses for Native Species
Urban and Rural Use and Perceptions of Natural Areas
Native American Perspectives on Natural Area Management
Role of Natural Areas in Ecosystem Management
Natural Hydrologic Regimes
Exotics in the Landscape
What is Natural: An Interdisciplinary Roundtable
Ecosystem Conservation
International Natural Area Conservation

Field Trips

Sandy River Gorge
Willamette Valley Natural Areas
Mt. St. Helens
Canopy Crane at Wind River
Puget Prairies and Puget Lowlands
Cascade Head Scenic Research Areas
Columbia River Gorge
Old Growth Pacific Northwest Forest
West Eugene Wetlands Project Area
Mt Hood National Forest
Berry Botanic Garden (half day)
Metropolitan Greenspaces (half day)

Page 6 Spring 1997

General Sessions

Exotic Species
Fire: Ecology, Public Perspectives and Use
Interpreting Our Natural World – Telling Stories through
Environmental Interpretation
Education and Other Uses of Natural Areas
Social and Ecological Implications of Grazing – Domestic and Wild
Invertebrates and Natural Area Management
Non-Vascular Plants and Natural Area Management
Forest Ecosystems
Fresh Water Ecosystems
Rare Species Management

Registration

Registration packets with complete conference information and
pricing are available in May. Full registration is $130, student
registration is $100, and daily registration is $55. NAA and
EPPC members automatically receive all conference mailings.
For questions, contact:
Natural Areas Association
PO Box 23712
Tigard, OR 97281-3712

Kathleen Bergquist
Conference Coordinator
Phone: (503) 579-2920
Fax:(503) 579-0468
Email: kbconnor@ix.netcom.com

CalEPPC News

Prescriptions for Applying
Herbicide to Tamarisk
Bill Neill, Desert Protective Council

D

eciduous tamarisk or
saltcedar is difficult or
impossible to kill by fire,
drought, freezing, hyper-salinity,
prolonged submersion, and repeated
cropping at ground level. In sensitive
natural areas, effective control of
tamarisk requires the careful application of systemic herbicide, lightly
sprayed either on freshly cut stumps
or girdled trunks, or the basal
portion of uncut saplings.

(Garlon 4 in solvent), and now either
Garlon 4 in vegetable oil or Pathfinder II.

The following prescriptions are
derived from my 14 years of experience as the Desert Protective
Councils volunteer coordinator for
tamarisk control, with long-term
projects at 40+ work sites in southern California and several more in
Nevada and Utah. Along the way,
control methods adopted by the
volunteer program have been
advanced by discussions with professional staff at DowElanco, the
Barstow BLM office, the Nature
Conservancys Coachella Valley
Preserve, Anza-Borrego Desert
State Park, Ash Meadows National
Wildlife Refuge, and Lake Mead
National Recreation Area.

Large trees
with isolated
trunks can be
more efficiently
treated by
girdling…

Herbicide Selection
Procedures for removing tamarisk by
non-aerial herbicide applications are
now a mature technology, and in my
opinion there is no need for further
experimentation.
Since 1983, the herbicide of
choice for cut-surface treatments
has progressed from Tordon RTU
(ready-to-use) to Tordon 101
mixed in water, straight Garlon 3A,
Garlon 4 mixed in water, Garlon 4
diluted in diesel oil, Pathfinder

At each stage, assessments have
been made of appropriate mixing
ratios, seasonal efficacy, cost and
user friendliness. All products are or
were manufactured by DowElanco
or its predecessor, Dow Chemical
Company.

For volunteer projects, the currently
preferred formulation is 25% Garlon
4 (which is 62% triclopyr), diluted in
generic food-grade vegetable oil at a
1:3 ratio. Addition of oil-soluble dye
is optional but usually not needed for
distinguishing treated stumps because the oil mixture darkens
stumps for hours after application.
Pathfinder II is the ready-to-use
version of Garlon 4 premixed at a
25% concentration in vegetable oil
or something similar. The solvent is
designed to enhance bark penetration and its derivation is a trade
secret. The retail cost of Pathfinder
II at about $30 per gallon is similar
to the cost of Garlon 4 and vegetable oil mixed at the same concentration.

When applied to tamarisk stumps
using spray bottles or pressurized
containers, the Garlon 4/vegetable
oil and Pathfinder II mixtures have
the advantages of being relatively
more efficacious, less toxic and less
aromatic to the applicator, and less
corrosive to spray-container valves
and seals, compared to previous
herbicide/diluent mixtures.
Cut-surface Method
In most cases a target tree or
sapling should be cut within 6 inches
of the ground surface using a
chainsaw, brush cutter or sturdy
anvil-blade lopping shears. Stump
heights should be as close to the
ground as feasible, without allowing
saw teeth or lopper blades to be
dulled or damaged by rocks or sandy
soil.
The stump surface should be lightly
sprayed with herbicide within several
minutes of cutting. Care should be
taken to wet the entire circumference of the barks cambium layer.
On large-diameter stumps, the
interior woody portion can be left
untreated to conserve herbicide.
In rocky stream courses, stumps
may require cutting higher that 6
inches to avoid chainsaw blade
damage. In such cases, to increase
herbicide efficacy, not only the cut
surface but also the bark on the
stump should be sprayed down to
ground level, but not to the point of
runoff. This additional treatment is
effectively the basal-bark method
described below.
continued next page
Spring 1997 Page 7

CalEPPC News

Tamarisk
(Contd)

Large trees with isolated trunks can
be more efficiently treated by
girdling, i.e. by making shallow,
overlapping cuts into the bark
around the trunk base using a
hatchet or chainsaw, and then
lightly spraying the entire cut surface
with herbicide. Substantial amounts
of labor can be saved by not felling
and removing large trees. However,
many large tamarisk trees have
multiple trunks radiating from the
root crown, and most limbs must be
removed to obtain access for the
herbicide treatment.
For applying herbicide to stumps, a
small finger-trigger spray bottle is
usually adequate. High-quality
bottles can be purchased at janitor
supply stores. Larger 1 to 2 gallon
hand-pump pressurized garden
sprayers with a hose and wand-type
nozzle may be useful for faster work,
as when a single applicator is
following several chainsaw operators
in a tamarisk thicket. It is important
to use hand-held rather than larger
backpack-type sprayers: leakage
from backpack sprayers is more
likely to contact the applicators, and
connecting hoses on the back side
are likely to be snagged on tree
branches and pulled off, causing
rapid uncontrolled drainage of the
herbicide tank.
The efficacy of Garlon 4 in cut-bark
applications shows no clear seasonal
dependency. Beyond the labels
caution that treatments may be less
effective during times of drought,
tamarisk removal may be scheduled
when outdoor working conditions
are most comfortable usually in
the autumn and spring seasons, but
also during winter when the tree is
dormant. However, where tamarisk
is intermixed with native trees, its
identification is more difficult during
Page 8 Spring 1997

winter months when the tree is
leafless; conversely, during autumn
and spring months, tamarisk recognition is aided by the plants yellow
foliage or pink flowers.
Basal Bark Method
Over the past several years, the lowvolume basal bark treatment method
described on the Garlon 4 label has
been successfully applied to tamarisk. It is an alternative to the laborintensive cut-stump method on trees
with trunk diameters less than 6
inches. Normally the lowest 12
inches of trunks are sprayed
without cutting with 20% to 30%
Garlon 4 in oil or with Pathfinder II.
The basal bark technique has been
employed extensively in remote
mountains canyons of Lake Mead
National Recreation Area, using a
mixture of 25% Garlon 4 in
Penevator basal oil; and at Coyote
Canyon in Anza-Borrego Desert
State Park, with the same herbicide
concentration carried in kerosene.
In the volunteer program, the basal
bark method has proved valuable at
Camp Cady Wildlife Area on the
Mojave River east of Barstow, in

treating tamarisk resprouts growing
from large debris piles left by a
major flood. Basal bark applications
of 20% Garlon 4 in diesel oil canceled the need for laboriously
dismantling the debris piles.
Advantages of the basal bark
method are that less labor is required, compared to cutting and
stump-spraying; and there is no
generation of cuttings that must be
piled on dry bare ground or dead
vegetation where they cannot root.
The disadvantage of basal bark
spraying is that more herbicide
mixture must be applied to each
stem perhaps 5 times more than
the cut-surface method because
more surface area is treated and
there is unavoidably more wastage.
Also, treatment success is less
definitive, and if a first treatment is
unsuccessful, a second treatment of
a surviving sapling will require more
time and herbicide than treatment of
a short resprouting stump.
The appropriate choice between
cut-surface and basal bark applications will depend on the balance of
labor resources and financial resources. In the volunteer program,

CalEPPC News

Tamarisk
(Contd)

the use of power saws followed by
workers to pile cuttings will remain a
fast and efficient method to remove
tamarisk trees on level ground. But
a smaller work force on rocky
terrain should find the basal bark
method to be clearly advantageous.
Although the Garlon 4 label directions do not refer to foliar applications, the treatment of resprouting
stumps may be considered a variation of the basal bark method.
Probably resprouts are most effectively treated when they have grown
to lengths of 4 to 8 inches when
the surface area of stems and leaves
is sufficient to absorb enough herbicide to kill the root crown, but not
so large that the consumption of
herbicide and applicator time is
excessive. Mixtures of 10% Garlon
4 in water or diesel oil are adequate
on previously treated stumps; but for
the more vigorous stems that
resprout after fires, a 20% concentration in oil is preferable for effective control.
Aquatic Applications
Although triclopyr decomposes in a
day or less in sun-lit water, Garlon 4
is not registered for aquatic use. For
cut-surface applications near surface
water, the recommended herbicide is
Monsantos Rodeo (glyphosate) at
full-strength concentration. Disadvantages of applying Rodeo, compared to diluted Garlon 4, are that it
is more expensive and less effective
at controlling tamarisk. Repeated
applications may be needed to
obtain control. The definition of
aquatic use refers to the potential
for trace amounts of herbicide to
enter surface water; stumps located
near but not rooted in water can be
legally treated with Garlon 4 provided that none enters water
although land owners and agencies

may require greater separation
distances to ensure compliance.
Tamarisk Control Strategies
In planning a tamarisk control
program, the first rule is to attack
outlying plants first rather than the
dense thickets. Reasons for this
strategy are outlined in my abstract
for the October 1992 CalEPPC
Symposium. The strategy of attacking outliers first may seem obvious to
some, but it counters the normal
human tendency to react more to
obvious problems than to potential
problems. The two best reasons for
this strategy in long-term projects are
(1) efficiency and (2) psychological
reward.
Efficiency means gaining control of
the problem with a minimum of
effort. The first objective of exotic
species control is to stop population
growth and prevent dispersal into
new areas. The outlying plants are
the main agents of seed dispersal.
Even if some seeds travel widely,
most land close to the parent plant
rather than far from it.
By removing outliers first, we avoid a
larger problem several years later.
Conversely, in established concentrations, waiting another few years has
not much effect: the exotic plants will
be larger, but they will compete

against each other, rather than
native plants, and the rate of
population increase will be slower
than in outlying areas.
Psychological rewards comes from
doing the easy work first, and
making rapid progress initially. At
an early stage, we establish large
areas that are now mostly free of
weeds, that we can monitor for
regrowth while we work on the
heavily infested areas. That early
sense of accomplishment is important when the work becomes
tedious and the total obligation
looks overwhelming. Currently this
control strategy is being systematically implemented by the Inyo
County Water Department in
removing tamarisk from northern
Owens Valley.
Desert areas most amenable to
tamarisk control are (1) canyons
and river channels subject to intense
flooding and (2) isolated springs that
are never flooded.
The susceptibility of a stream
channel to erosive flooding should
be evident from the age and size
structure of the trees on its banks.
A typical history of variable episodic
continued next page
Spring 1997 Page 9

CalEPPC News

Tamarisk
(Contd)

flooding will result in seedlings or
relatively young saplings growing on
the channel floor, and progressively
older and larger trees encountered
higher on the banks.

follow-up inspections should be
scheduled after 3-4 months have
passed, so that there is no uncertainty over which stumps are dead
and which are alive.

Along flood-prone streams, tamarisk
removal should start with larger trees
located high on stream terraces that
are likely to survive future floods and
reseed the stream floor; younger
trees and saplings growing lower in
the channel can be ignored as they
eventually will be washed away. To
be most effective, removal work
plans should be opportunistic with
respect to flood events: for example,
after trees located above the fiveyear flood level are eliminated,
subsequent work can be delayed until
a erosive flood does occur, after
which a concentrated effort is made
to remove the surviving trees.

Tamarisk trees on floodplains can be
more difficult to kill, requiring
several treatments. The root systems
are more extensively developed near
the ground surface, due to repeated
scouring and removal of limbs by
floods, and can send up shoots
where none existed at the time of
initial treatment.

Around isolated desert springs that
are never flooded, tamarisk removal
must be total to be effective. But
because seeds are generally not
viable for longer than one year, once
accomplished, the rehabilitation
should be permanent, with only
occasional surveillance needed to
remove seedlings derived from
distant seed sources.
One potential problem of spring
rehabilitation is that increased water
flow resulting from partial tamarisk
clearance may flood new areas and
cause new seedling growth outside
the area of original infestation, thus
increasing the ultimate amount of
work needed for control. This
sequence of events occurred both at
Eagle Borax Spring in Death Valley
and at Red Rock Canyon State Park
in California. The lesson to be
learned is that tamarisk clearance
near springs should be completed in
a single winter season, if possible.
Page 10 Spring 1997

Otherwise, cutting should proceed
inward from the perimeter, with
trees closest to the spring saved for
last; and if water flow returns or
increases during summer months
before clearance is completed,
flowering branches should be cut off
without ground-level herbicide
treatment to curtail seed production.
Tamarisk control will be most
difficult, and perhaps impossible,
around reservoirs with fluctuating
water levels and on river courses
which flood enough to cause
widespread seed propagation, but
not erosively enough to uproot
established trees.
Post-application Monitoring
Under favorable conditions the
mortality rate of tamarisk after cutsurface herbicide treatment should
exceed 95%. Less successful
applications are usually attributable
to not cutting the bark circumference completely or low enough to
ground level, or not spraying soon
enough after cutting.
Some amount of regrowth is
inevitable. A follow-up visit to treat
resprouting stumps is always
necessary several months to a year
after an initial treatment. In some
cases during the spring months, a
treated stump will produce short
stems before dying. Therefore

Although proper application technique is important, it is necessary to
find a balance between working with
thoroughness and working with
speed. When confronting shallow
lateral roots or partly exposed root
systems, for example, it is more
efficient to work quickly on the first
pass; then, after seeing what survives, spend more time on follow-up
visits treating the more inaccessible
roots.
Following fires or clearance by
bulldozer, tamarisk resprouts should
be sprayed as early and as frequently
as feasible. There is no advantage to
letting resprouts from untreated root
systems grow to some desired height
before initial spraying.

For more information, please
leave a message at:
714.779.2099 in California
or 281.287.5246 in Texas.

CalEPPC News

Call for Nominations

Submission Deadlines
for CalEPPC News

bout this time of year CalEPPC begins its annual election
process with a call for nominations to our Board of Directors.
The CalEPPC Board consists of a President, Vice-president,
Secretary, Treasurer, 10 at-large members, and the past years
president. All board members are volunteers; none are paid. The four
officers are elected for one-year terms. The at-large board members
serve for two years, half elected in even years, half in odd years. All
terms commence January 1, 1998. Hence this year, the four officer
positions are open and five at-large positions are open.

If you would like to submit a news item,
an article, a meeting announcement or
job opening for publication in 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:

A

We encourage members to consider serving as an officer or an
at-large member of the Board of Directors. If you would like to place
your own name, or the name of another member in nomination,
just drop a note to John Randall at TNC Wildland Weeds Mgmt.,
UC Section of Plant Biology, Davis, CA 95616.

CalEPPC News
Sally Davis, Editor
31872 Joshua Dr., No. 25D,
Trabuco Canyon, CA 92679
phone: 714.888.8541
email: sallydavis@aol.com
Issue

Summer, 1997
Fall, 1997
Winter, 1998
Spring, 1998

Deadline

July 15, 1997
October 15, 1997
January 15, 1998
April 15, 1998

If you are nominating yourself, please include a short 100-word
biography. If you are nominating someone else, please include their
telephone number so we can call and ask if the nomination is
accepted.
Your currently elected Board of Directors is listed in this
newsletter on Page 2.
Arundo donax
Sally Davis

Calendar of Events
May 17

The Natural History of Pinnacles National Monument, Pinnacles National Monument, CA.
Sponored by UC Santa Cruz Extension. Cost $79.00. Contact: 800.660.8639.
May 22-23
Working Together for Common Ground: Breaking Down the Barriers for Cooperative Resource
Management, Santa Cruz, CA. Sponsored by California Coordinated Resource Management and
Planning. Cost $45/one day, $6/two days. Contact: 916.447.7237; email:
May 30
GIS Tools and Solutions: Can They Work for My Organization? San Francisco, CA. Sponsored by
UC Berkeley Extension. Cost $235. Contact: 510.643.7143.
June 11
Endangered Species: Protection and Regulations, Davis, CA. Sponsored by UC Davis Extension.
Cost $235. Contact: 800.752.0881.
June 20
SER Riparian Guild Meeting, San Jose, CA. Sponsored by the Riparian Guild. Cost $5.
Contact: Bernie Goldner, 408.438.1874; email:
July 23-26
Interactions: managing Ecosystems on a Watershed Basis, Toronto, Ontario, Canada, sponsored
by the Soil and Water Conservation Society. Contact: 515.289.2331 or 800-843.7645;
fax 515.289.1227; email:
August 27-30 Bridging Natural and Social Landscapes, the 24th Natural Areas Association Conference,
Portland, OR. co-sponsored by CalEPPC and PNWEPPC. Contact: Reid Schuller,
541.388.8123; fax 541.388.5414.
October 10-12 Reaching Out and Keeping Out, CalEPPC Symposium 97, Concord, CA. Contact: Sally Davis,
714.888.8541; email:
Spring 1997 Page 11

1997 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!
q Status

Individual

Institutional

Name

q Retired/Student*

$15.00

N/A

Affiliation

q Regular

$25.00

$100.00

Address

q Contributing

$50.00

$250.00

q Sustaining

$250.00

$1000.00

q Lifetime

$1000.00

N/A

Please make your check payable to CalEPPC and
mail with this application form to:
CalEPPC Membership
c/o
Sally Davis

31872 Joshua Drive, #25D
Trabuco Canyon, CA 92679-3112

City/State/Zip
Office Phone
Home Phone
Fax
email

* Students, please include current registration and/or class schedule

CalEPPC Sponsors & New Members
1997 Corporate Sponsors: Individuals or Organizations who have
contributed $100 or more to CalEPPC
AFFINIS
Barrie Coate & Associates
California Native Plant Society
Caltrans Environmental/Sacto
Dunsmuir Botanic Gardens
Hedgerow Farms

Huntington Library
Jepson Herbarium
Jones & Stokes Associates
Monsanto Company
Pestmaster Services
Redwood National Park

SePro
Strybing Arboretum
Tree of Life Nursery
USGS Biological Services
Wilbur-Ellis Company

CalEPPC would like to welcome the following people who have joined in
the months from February through April 1997:
Janice Alexander
Jennifer Drewitz
Kim Henney
Jodie Holt

CALIFORNIA
EXOTIC
PEST PLANT
COUNCIL
31872 Joshua Drive, #25D
Trabuco Canyon, CA 92679-3112

Deborah MacAller
Mara Noelle
Charles Nohejl
Elyssa Robertson
NON-PROFIT ORG.
U.S. POSTAGE

PAID

TRABUCO CANYON, CA
PERMIT NO. 7