Emergent Invasive Report: June 3, 2017
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Canary Island St John's Wort (Hypericum canariense):

Detected in Laguna Canyon on May 18th and reported through the Emergent Invasive Program. It was quickly field checked, roughly mapped and can be seen on Calflora (here). This is a significant infestation of a highly problematic plant. It is a large woody shrub and appears to readily invade intact native plant communities. Land managers, conservation organizations and others are currently in communication about next steps. More information about this infestation can be seen here.

Barbed goatgrass (Aegilops triuncialis):

In late May a recurrence of a 2015 detection of this invasive grass was found at Audubon’s Starr Ranch. This is the first location in OC for this non-native invasive annual grass that still has limited distribution in SoCal.  The California Invasive Plant Council classifies its potential impact on native ecosystems as high. The Ranch is working on a control strategy. More info here.

Boneseed (Chrysanthemoides monilifera):

We received a bit of good news regarding the infestation near the mouth of Aliso Canyon. An allied organization, active in the area, has agreed to assist OC CNPS with coordination of the land managers and agencies that will likely be involved in future management. More to come on this.

Long flowered veldtgrass (Ehrharta longifolia):

Fred Roberts detected a small colony of this invasive in late April in the Bonita Canyon area, a first record for OC. Management is pending.

Water hyacinth (Eicchornia crassipes):

An undetermined number of plants were detected in March or April in San Diego Creek Channel near the Audubon House and Duck Club. More to come.

Japanese dodder (Cuscuta japonica):

A report of invasive Japanese dodder (Cuscuta japonica) at Laguna Coast Wilderness Park in late April appears to be erroneous.

Coastal galenia (Galenia pubescens):

Detected by an OC CNPS member in the Laguna Coast Wilderness Park in April and reported through the Emergent Invasive Program. This is the first OC detection of this species. It has been successfully responded to by  Laura Cohen, the resource specialist at the park. She reported that more than 500 plants were removed. Initial Calflora record is here. A secondary report is here.

Volutaria (Volutaria tubuliflora):

Volutaria management continued at Upper Newport Bay from late winter through spring and has now concluded for the season.

Non Toxic Communities:

We are monitoring several of the “non-toxic” efforts in various OC communities. We are concerned about losing herbicides as a critical tool in the management of invasive plants in wildland areas. Thus far the cities of Irvine and San Juan Capistrano have passed ordinances forbidding the use of synthetic herbicides from all public areas.

Cal-IPC Symposium:

The Cal-IPC annual symposium will be Oct. 24-27 in Palm Springs. The OC CNPS Invasive Committee is preparing new posters and handouts to display on the sponsor table. This will outline steps for other groups to establish their own Early Detection – Rapid Response (EDRR) program.

At the Cal-IPC symposium, Ron Vanderhoff of OC CNPS will be presenting as part of a Volutaria session, discussing the Newport Bay detection, infestation and management.

Santa Ana River & Orange County Weed Management Area update:

A meeting on May 24 at Santiago Oaks Regional Park was well attended, especially by OC members. The meeting including a live training and demonstration on the use of the Calflora software. This online database, record keeping and weed management tool is used by many land managers and the public. Several customizations and advanced features for reporting and management tracking were reviewed.

The March WMA meeting was in Riverside and attended by OC CNPS committee co-chair Jutta Burger. Jutta gave updates of OC CNPS invasive activities and also relayed updates from the other regional members to our chapter committee.

Coastal NCCP Invasive Survey:

The OC Coastal NCCP (Natural Communities Coalition) is continuing its spring survey of approximately 150 miles of trails throughout the coastal area, including lands within OC Parks, CA State Parks, Irvine Ranch Natural Landmarks, Irvine Open Space areas and others. James Bailey is conducting the surveys and has been reporting on a specific list of priority invasive plants, as well as other non-native species new to the region.

The Cal-IPC Invasive Inventory:

OC CNPS has been active in Cal-IPC reviews of dozens of species for possible inclusion in their Invasive Species Inventory. The scientific reviews have been completed, the public comment period has concluded and the results will be made public within the next few weeks. This is a significant update to the inventory.

Other Committee Tasks and Follow-ups:

Checking on our two OC Parthenium infestations (Santa Ana and Irvine)
Following up on the management of a small yellow flag iris (Iris pseudacorus) infestation at Upper Newport Bay
Ongoing stinknet (Dittrichia graveolens) management in Arroyo Trabuco (year 4)
Ongoing yellow star thistle management (Centaurea solstitialis) management in Silverado Canyon and along Hwy. 74 (years 3 and 4).
Emergent Invasive Report: May 3, 2017

Coastal NCCP Invasive Survey:

The OC Coastal NCCP is continuing its spring survey of about 150 miles of trails throughout the coastal NCCP area, including lands within OC Parks, CA State Parks, Irvine Ranch Natural Landmarks, Irvine Open Space areas and others. James Bailey is conducting the surveys and has been reporting on a specific list of priority invasive plants, as well as other non-native species new to the region.


Volutaria management continued at UNB, both on the Big Canyon colony - and the Irvine Blvd. colony

New Invasive, Galenia pubescens - coastal galenia:

The first OC detection of Galenia pubescens in the Laguna Coast Wilderness is successfully being responded to. Laura Cohen, with Laguna Coast Wilderness Park is handling the rapid response management, following a report through the OC CNPS Emergent Invasive Program. Laura reported this afternoon that more than 500 plants were removed and she believes they are only half way done.

Possible Cuscuta japonica - Japanese dodder

possible detection of invasive Japanese dodder (Cuscuta japonica) was reported to Laguna Coast Wilderness in late April and then to OC CNPS. We are working on verifying this report before beginning additional communications or suggesting a Rapid Response.

New Invasive, Ehrharta longofolia - longflowered veldtgrass

In late April, Fred Roberts detected a colony of the invasive Ehrharta longifolia - longflowered veldtgrass, in the Bonita Canyon area, a first record for OC. Treatment is TBD.

Cal-IPC Symposium

There may be a Volutaria presentation at the 2017 Cal-IPC Symposium in Palm Springs on October 24-27. OC CNPS may assist with parts of the presentation.


Ron Vanderhoff has been asked by PlantRight, the principal organization working to remove invasive plants for the horticulture trade, to assist with reviewing a list of possible ornamental invasive species, using the PRE screening tool.

Weed Management Area Meeting

The next WMA meeting on May 24th will be at Santiago Oaks Park, 11am-2PM which will include Calflora training via screenshare and OC-CNPS emergent species documentation.

Herbicides for Invasive Plant Management

On May 1, Huntington Beach City Council approved a one-year test of Organic-only pesticides in a portion of HB Central Park. Updates will be provided to city council at six month and twelve month intervals. This is similar to the decisions that occurred in Irvine and San Juan Capistrano, leading to their new no-synthetic-pesticide ordinances.


A few other random reports of non-native detections came in on various species, but mostly re "former" emergent species. Nothing significant.

Emergent Invasive Report: Apr 6, 2017

Chrysanthemoides - boneseed:

It is a long and complex story, but we believe we discovered how the first Chrysanthmoides - boneseed plant arrived in Lauguna Beach. It was apparently planted by legendary Laguna Beach gardener Hortense Miller. The original plant, now quite old, was still growing in her garden. OC CNPS worked with the garden leadership and it was agreed that the plant would be removed.

Weed Management Area Meeting:

The March WMA meeting was in Riverside and attended by OC CNPS committee co-chair Jutta Burger. Jutta gave updates of OC CNPS activities and also relayed updates of other regional invasive plant activities back to our chapter committee.

Natural Communities Coalition:

The OC Coastal NCC has contracted with Robb Hamilton, who has in turn employed James Bailey, to survey about 150 miles of trails throughout the coastal NCC area, This includes lands within OC Parks, CA State Parks, the Irvine Ranch Natural Landmarks and others. He has already begun the surveys and will be searching for and reporting on a specific list of priority invasive plants. He will also be search for new and unknown possibly invasive plants that may be new to the region.


Volutaria management is continuing at UNB, both on the Big Canyon colony - with IRC, and on the Irvine Blvd. colony - with OC Parks. A possible volunteer pull for late March at the Irvine Blvd. colony was cancelled due to good management by OC Parks contractors and OC Parks/LCF (Laguna Canyon Foundation) volunteers. The feeling was that there was not enough Volutaria remaining for a seperate volunteer event.

Also regarding Volutaria, James Bailey, working under the coastal NCC, surveyed trails in both areas and communicated additional detections and a current status to the managing agencies.

New Species Detection:

On 3-31 Jonathan Frank, a CNPS member, detected a first OC occurrence of Galenia pubescens in the Laguna Coast Wilderness. His detection was reported to the OC CNPS Emergent Invasive Committee and others. The detection has been passed through to OC Parks and CA State Parks biologists and to the coastal NCC. OC CNPS is proceeding cautiously until we know the severity of the infestation and have adequately assessed the invasive threat of this species.


A few other random reports of non-native detections came in on various species, but mostly re "former" emergent species. Nothing significant.

Emergent Invasive Report: Mar 7, 2017

Cal-IPC is proposing additions their California Invasive Plant Inventory and soliciting input during a 60-day comment period. 

They are proposing to add:

  • Ten plant species that are currently deemed invasive in California, based on completed assessments of impact and spread
  • 87 species deemed to be a high-risk for becoming invasive in California. (We completed assessment for 200 species established outside cultivation in California, and these 87 are those that scored “high-risk.”)

You can view all information at http://cal-ipc.org/ip/inventory/update.php, including individual assessments, summary tables, the project team, and how to submit comments.

The 60-day public comment period runs from March 8 to May 8. The project team will post responses to input received, and for plant species whose categorization changes based on input received from this review period, the project team will post the revised assessments for a subsequent 30-day comment period

Emergent Invasive Report: Feb 24, 2017
Volutaria Assistance Needed:
Volunteers are needed (no experience required) to remove Volutaria from Borrego Springs this spring. Volutaria tubuliflora is a new and highly invasive weed in Southern California. This would be a great opportunity to remove a highly invasive weed before it becomes a widespread problem as well as visit Borrego Springs for some desert recreation. The Borrego Springs infestation occurs on 20 sites scattered over a 5 mile span and is in desperate need of volunteers to pull/hoe weeds as well as map the spread. If interested contact  Chris McDonald, . Mid-Feb and March. Depending on availability, The UCI Anza-Borrego Desert Research Center has offered overnight facilities (approx. $40 or less per person) to Volutaria pullers.
More Volutaria: 
Seperately, OC CNPS, OC Parks and The Newport Bay Conservancy are coordinating a Volutaria pull at Upper Newport Bay, the sight of the second of three US. Volutaria infestations. Details and dates are not ready at the time of this publication, but is likely to be in mid to late March. If you would like to be notified of this and other local invasive plant opportunities please send a brief note to .
Weed Management Area:
OC CNPS was well represented at a January Weed Management Area (WMA) meeting in Irvine. Several discussions ensued about Orange County invasive plant issues and activities. OC CNPS is now an active member of this important collaboration and Orange County will now be represented. It was decided that future quarterly meetings of this WMA will be alternated between Riverside and Orange County.
On Feb. 2:
Cenchrus echinatus was confirmed at San Onofre State Park.
On Jan. 19:

The OC CNPS general meeting in Irvinewas devoted to the chapter's Emergent Invasive Plant Management Program. 60 members and guests participated.

On Jan. 8:

A survey by OC CNPS revealed a new large colony of Volutaria tubuliflora at Upper Newport Bay on the mesas adjacent to Irvine Blvd. The population appears to number in the thousands. The colony was mapped and posted to Calflora. Several interested parties, including OC Parks, Cal-IPC and others were notified, with management beginning on January 16.

Emergent Invasive Report: December 29, 2016

On Dec. 29:
Ehrharta calycina - perennial veldt grass in Emerald Canyon, Laguna Coast Wilderness Park, was visited and mapped by OC CNPS.
Brassica tournefortii - Sahara mustard. A new colony was detected and mapped on Big Bend Trail, Laguna Coast Wilderness.
On Dec. 25:
Brassica tournefortii - Sahara mustard. A new colony was detected and mapped just off Laguna Canyon Road, near the intersection of Forest Drive, Laguna Beach.
On Dec. 17:
The OC CNPS Emergent Invasive Committee met. Among other business: a thorough species review,  additions and deletions to the Emergent Invasive plant list for 2017, discussion of an Orange County Weed Management Area and possible collaboration with the Orange County Natural Communities Coalition (NCC).
On Dec 1:
A second small colony of a Chrysanthemoides colony in lighly maintaned landscaping off Nyes Place in Laguna Beach was re-examined by OC CNPS and determined to be the non-invasive species Chrysanthemoides incana, not the highly invasive Chrysanthemoides monolifera.
On Nov. 13:
Two additional colonies of Delairea odorata - cape ivy were discovered and plotted by OC CNPS.
On Nov 10: 
The expanding colony of Senecio linearifolius - Australian linear-leaved fireweed along Pacific Island Drive in Laguna Niguel was accurately plotted and posted to Calflora by OC CNPS.

Emergent Invasive Report: November 7, 2016

On Nov. 3:
Parthenium hysterophorus - Santa Maria feverfew. CDFA just published a CA Pest Rating Proposal to list this species as an "A" rated pest. The public comment period opened and ends December 17. OC CNPS posted a statement of support on this proposal.
The two detections in Orange County (in which our committee has been the catalyst) precipitated the proposal. Currently, these are the only two extant occurrences in CA. The OC Ag Commissioner is managing the main population in Santa Ana and the two plants located in the San Diego Creek Channel (not far from the Duck Club) were both removed earlier this summer.
On Oct. 22:
Lepidium latifolium -  perennial pepperweed. A new three acre population was discovered and plotted in a basin near MacArthur Blvd. and Bison Street, Newport Beach.
On Oct. 16:
Iris pseudacorus - yellow flag Iris. A population along Laguna Creek (OC's largest) was visited during management efforts. The Laguna Canyon Foundation, in conjunction with The City of Laguna Beach, has contracted with The CA Conservation Corps to perform storm channel work and invasive plant removal in this corridor. The CCC team was present during the visit, along with three biologists. Management guidance for the iris was offered by OC CNPS, especially the importance of complete rhizome removal and disposal.
On Oct. 14:
Volutaria tubuliflora - Moroccan knapweed. During research on a related species OC CNPS discovered possible records dating to 2003, and maybe as early as 1987. A photograph and comments of "Centaurea muricata" by Robert DeRuff (deceased) is made in The Vascular Plants of Upper Newport Bay. A voucher specimen of the same record was deposited at the UC Riverside herbarium, also under the name Centaurea muricata. We now believe these records may refer to Volutaria tubuliflora. In the records Mr, DeRuff mentions both Big Canyon and the bluffs not far from the Muth Center, both locations of our 2015 and 2016 records. 
If the specimen at UCR is confirmed as Volutaria tubuliflora this would move the date of California introduction forward by at least several years and would also change the introduction point from Boreggo Springs to Newport Beach.
On Oct. 12:
Parthenium hysterophorus - Santa Maria feverfew. The OC Ag Commssioner's office reported back to OC CNPS that the colony in Santa Ana, discovered by us on Sept. 1 has been removed. They also reported that the property owner is cooperative and that the site will continue to be visited at regular intervals to ensure control. Thais is the second or third record for CA and a high priority for CDFA.

Emergent Invasive Report: September/October, 2016

On Oct. 8:
One of SoCal's best botanists, Rick Riefner, detected and reported a colony of the highly invasive boneseed bush - Chrysanthemoides monolifera in Newport Beach. The colony was site checked, mapped and posted to Calflora the following day. This is the third detection in Orange County and perhaps only the fourth in the U.S.

On Sept. 23:
On Friday we participated in a second conference call regarding a proposal for Volutaria tubuliflora (knapweed) eradication in Southern California (three sites). The group includes participants from Cal-IPC, S.D. County Ag, UCCE, UCR, CDFA, S.D. Co. Public Works, Anza-Borrego S.P., IRC and volunteers.
The working group is centered around a Cal-IPC grant request to The National Fish & Wildlife Foundation. A funding decision is expected in early January, with on-the-ground action beginning Immediately thereafter. By far, the Anza-Borrego infestation is the most serious, but the Newport Bay colony is also significant, esp. due to its urban location and potential for further dispersal. 

A local byproduct of this effort would be the development of an Orange County WMA, which currently does not exist. Here are highlights of the OC related parts of the call:
  1. We are requesting a systematic Volutaria tubuliflora survey of the greater Upper Newport Bay Area. A small second population (five plants) were found a mile away in Jan. '16 and there is concern that we may not know the full extent of the population and need to accurately delimit the infestation.
  2. IRC has a good handle on the Big Canyon infestation and we have high confidence in their management success - if indeed Big Canyon area is the extent of the infestation.
  3. The Newport Bay Conservancy is a good source of volunteers and an important liaison.
  4. The small new population (five plants near the Muth Center) is on Orange County Parks land. It was suggested that both OC Parks and City of Newport Beach be included in the larger stakeholder group.
Following the call, Riley Pratt (IRC), Doug Johnson and Ron Vanderhoff briefly discussed the possibility of OC Ag involvement. OC Ag has the authority to set emergency quarantines and protocols involving the movement of green waste off of infested sites. Volutaria seed is wind dispersed and we have concern about propagules being moved from the site. We also briefly discussed the need for protocols regarding the City's ongoing fire abatement in the Big Canyon area.
On Sept. 21:
Cal-IPC is submitting comment to the California Wildlife Conservation Board (WCB) on their draft "conservation vision," which will guide their work over the next five years. WCB has funded two regional early-eradication projects in the last two years, which is a good start. A lot more needs to be done, and stopping invasive plants should be made an explicit priority in their planning. Unfortunately, WCB's draft plan does not even mention invasive species. OCCNPS was asked to sign-on as an endorser of this request, which OC CNPS has done.

On Sept. 15:
Dave Pryor and Ron Vanderhoff met with Laguna Canyon Foundation restoration biologist Alan Kaufman to discuss invasive plant removal in portions of Laguna Canyon Creek. We specifically observed the Delairea odorata - cape Ivy and Iris pseudacorus - yellow flag Iris infestations and discussed management options. Via a Laguna Beach city grant, the foundation is restoring portions of the watershed, which includes removal of these and other invasive plants. The foundation is also directing work by the CA Conservation Corps in other portions of the creek, where yellow flag Iris colonies exist.
A follow-up visit on Oct. 6, during the removal work, provided additional guidance. Present were Alan Kaufman and Josie Bennett of LCF, invasive management specialist Henry DeRocco and a crew from the CA Conservation Corps.
Other News
  • Joan Miller, a CNPS member and volunteer with OC Parks and others, is in communications with OC Parks and the City of Laguna Niguel to begin management of the Senecio linearifolius Australian linear-leaved fireweed in portions of Salt Creek, from near PCH to north of Camino Del Avion. The infestation is significant.
  • Control is complete this year on the stinkwort colonies (Dittrichia viscida) in the Arroyo Trabuco and on Hwy. 74.
  • Control is complete this year on the Centaurea solstitialis - yellow star thistle colonies along Hwy 74.
  • Additional plants or colonies were discovered of Araujia sericifera - bladderflower (Irvine), Asphodelus fistulosus - onionweed (Laguna Niguel), Robinia pseudoacacia - black locust (Laguna Beach and San Juan Capistrano), Rubus armeniacus - Himalayan blackberry (San Juan Capistrano) and Senecio linearifolius - Australian linear-leaved fireweed (Laguna Niguel).
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