This would be a great opportunity to kill a highly invasive weed before it becomes a widespread problem as well as visit Borrego Springs for some desert recreation. Volutaria has been found in three disjunct populations in Chula Vista, Newport Beach and Borrego Springs. The Borrego Springs infestation occurs on 20 sites scattered well over a 5 mile span and is in desperate need of volunteers to pull/hoe weeds as well as map the spread.
Although it is aggressively spreading in Southern California this weed could be eradicated from California. If it is not stopped at this early stage, it is likely to spread into many plant communities across California and become a permanent and unwanted addition to our flora.
Dates are likely mid-late Feb as well as early March. Please specify or if there is a large demand we will make a doodle poll with options.
The UC Irvine Steele/Burnand Anza-Borrego Desert Research Center has offered to let volunteers stay at the facility overnight (cost approx. $40 or less per person) if they will pull Volutaria, depending on the availability of the center. The center is normally only open to research groups and classes and is filling up fast. Alternatively, one could make a day trip to Borrego or stay at a local hotel.
Chris McDonald PhD
Natural Resources Advisor
County Co-Director, San Bernardino
UC Cooperative Extension
Emergent Invasive Report: December 29
Emergent Invasive Report: November 7
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.
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.
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.
The Newport Bay Conservancy is a good source of volunteers and an important liaison.
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.
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:
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).