Re: Red palm weevil alert from CDFA


Ben,
Keeping a Phoenix palm healthy and hydrated does not seem to inhibit infestation in the slightest.  It is possible to inject the palms with systemic insecticides and keep them safe for up to 6 months, with several insecticides that are readily available for home use being possible treatments.  I don't think it is realistic to think the average homeowner will be willing to take such continual efforts to protect their palms, and of course it isn't safe to use such systemic poisons on edibles such as Dates.

Obviously not all palms have been wiped out everywhere they are grown in Europe, but it may be that Phoenix canariensis will be very rare sightings outside of the Canary Islands themselves, and more northerly locations such as Normandy and southern England where there are successful plantings of Phoenix canariensis.  Isolated plantings of palms are less at risk of attack, as the weevil is a poor flyer, and not able to spread on its own across large bodies of water.  The localized infestations of this weevil already in the Caribbean are not thought to be much of a risk to Florida or unaffected other islands as long as infected palms aren't physically moved from island to island or to Florida.

While there are not really that many species of palms that are native to Mediterranean Climate Zones around the world, the ones that are native are certainly beautiful examples of the flora, and include Phoenix canariensis, Chamaerops humilis and C. humilis v. cerifera, Jubaea chilensis, Washingtonia filifera and a few more obscure Phoenix species, off the top of my head.  I think our urban landscapes would be less beautiful as well as less diverse if we couldn't grow these palms anymore.


From: Ben Wiswall <benwiswall@pacbell.net>
To: medit plants forum <medit-plants@ucdavis.edu>
Sent: Tue, November 16, 2010 1:13:55 PM
Subject: Re: Red palm weevil alert from CDFA

Hi David, Hi Karrie,
Thanks for the update on Red Palm Weevil: I think the lack of response may just be it's the latest news, and we're all still digesting it: I just read about it I think in the LA Times this weekend.

Is there any way to control the weevil, especially assuming complete eradication is not possible?
Is it like the lerps that attack eucalyptus?  I understand that a well-tended eucalyptus in a garden can be saved from lerps, while wild (feral?) eucs growing undisturbed in the countryside are wiped out.

What is the experience with the weevil in southern Europe?  Are there no more palms left?

-Ben Armentrout-Wiswall
Simi Valley, southern California



From: Andrew Beith <ajbeith@telefonica.net>
To: medit plants forum <medit-plants@ucdavis.edu>
Sent: Tue, November 16, 2010 12:42:59 PM
Subject: Fw: Red palm weevil alert from CDFA

 
----- Original Message -----
From: a*@telefonica.net
To: s*@ucdavis.edu
Sent: Tuesday, November 16, 2010 5:46 PM
Subject: Re: Red palm weevil alert from CDFA

Sorry to hear about this confirmation.
Don't underestimate this weevil: it is large (5cms/2 ins long), producing 3 or 4 generations a year, doesn't necessarily bother to search for new palms until it has finished with its current host, therefore lives in large colonies(up to 300 have been found in one palm), and when it does fly it can go up  to 3 miles.Pruning and shaving of palms is prohibited here (Mallorca, Spain) in infected areas.
Good luck.
Andrew Beith
----- Original Message -----
From: s*@ucdavis.edu
To: m*@ucdavis.edu
Sent: Tuesday, November 16, 2010 4:40 PM
Subject: Red palm weevil alert from CDFA

Here is the alert sent out by CDFA:

RED PALM WEEVIL, WORST KNOWN PEST OF PALM TREES,

DETECTED IN LAGUNA BEACH

Agricultural officials confirm first detection of palm tree pest in the United States

 

SACRAMENTO, October 18, 2010 - Agricultural officials have confirmed the detection of a red palm weevil in the Laguna Beach area of Orange County - the first-ever detection of the pest in the United States. The weevil is considered to be the worldâs worst pest of palm trees.  An infestation typically results in the death of the tree.

 

âThis invasive pest is a threat not only to our nursery growers and date palm farmers,â said California Department of Food and Agriculture (CDFA) Secretary A.G. Kawamura.  âIt also endangers all of the decorative palms that are so common in our landscape and so much a part of the classic California backdrop.  I would like to express my gratitude to the landscape contractor who originally reported this pest. He is a Good Samaritan who did the right thing when he took the time to notify local agricultural authorities, and he has given us a very valuable head-start in our efforts.â

 

In response to the original contact by the landscaper, state and local agricultural officials, working in partnership with the USDA, began an extensive, door-to-door survey in the neighborhood and are setting about 250 traps to determine if an infestation exists.  Protocols for this pest call for an initial survey covering a 1.5 square mile radius around the detection property, resulting in a trapping array covering nine square miles.

 

The red palm weevil, scientific name Rhynchophorus ferrugineus, is a major pest of palm trees, many of which are highly valued as landscaping plants, generating approximately $70 million in nursery plant sales in California annually. Palm trees are also used for producing crops and marketable agricultural commodities including coconuts, dates and oils.  In California, date palm growers harvest an annual crop worth approximately $30 million.  The vast majority of these farms are in the Coachella Valley region. 

 

The red palm weevil is native to Southeast Asia and has spread throughout the Arabian Gulf.  It is found in parts of Asia, Africa, the Middle East, Europe and Oceania.  Prior to the detection in Orange County, the closest confirmed infestation to the United States was in the Dutch Antilles in 2009, the first report of the pest in the western hemisphere.  It was also confirmed in Aruba in 2009.

 

Female red palm weevils bore into a palm tree to form a hole into which they lay eggs.  Each female may lay an average of 250 eggs, which take about three days to hatch.  Larvae emerge and tunnel toward the interior of the tree, inhibiting the treeâs ability to transport water and nutrients upward to the crown. After about two months of feeding, larvae pupate inside the tree for an average of three weeks before the reddish-brown adults emerge. Adults live for two to three months, during which time they feed on palms, mate multiple times and lay eggs.

 

Adult weevils are considered strong fliers, venturing more than a half-mile in search of host trees.  With repeated flights over three to five days, weevils are reportedly capable of traveling nearly four-and-a-half miles from their hatch site.  They are attracted to dying or damaged palms, but can also attack undamaged host trees.  Symptoms of the weevil and the larval entry holes are often difficult to detect because the entry sites can be covered with offshoots and tree fibers.  Careful inspection of infested palms may show holes in the crown or trunk, possibly along with oozing brown liquid and chewed fibers.  In heavily infested trees, fallen pupal cases and dead adult weevils may be found around the base of the tree.

 

Residents are encouraged to report suspect infestations by calling the CDFA Pest Hotline at 1-800-491-1899.

Steve Lyle

Director of Public Affairs

California Department of Food & Agriculture

(916) 654-0462

-- 
Karrie Reid
Environmental Horticulture Advisor
UC Cooperative Extension, San Joaquin County
2101 Earhart Ave., Ste 200
Stockton, CA 95206-3924

209-953-6109
FAX: 209-953-6128



Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index