Re: white fly

This is an incredibly valuable, knowledgeable, clear and helpful response and I learned a lot from it, and also gained two helpful resources from the attachment and link, and I just wanted to say a big thank you, Karrie, for taking the time and making the effort to write it. 

S.





>________________________________
> From: Karrie Reid <skreid@ucanr.edu>
>To: medit-plants <medit-plants@ucdavis.edu> 
>Sent: Wednesday, 12 June 2013, 3:30
>Subject: RE: white fly
> 
>
>
> 
>Hello Kay,
>Iâm going to respond to this from my âofficialâ email, in my official capacity. First of all, the key to any pest control is correct ID. There are several kinds of whitefly, and they donât all respond to the same kind of treatment. For instance, I had an incredible infestation of Giant whitefly on my cannas last year (one of its favorite hosts), and noticed that it was in my neighborhood festooning huge shiny Xylosma shrubs and a number of its other hosts. The most effective treatment for that one is to cut out the material too heavily infested to be sprayed away with water. Fortunately, it doesnât fly very far, and if you remove it, you can get pretty good subsequent control. I have yet to see it at all this year. The thing about whitefly is that it has several natural enemies, and with a mild infestation, if you can hold off using chemicals, the predators finally come a little late to the party and keep things under control,
 just like ladybugs and aphids. If you use broad spectrum insecticides too soon, you end up killing off all the beneficial insects as well, and you end up in the vicious cycle of having to use it again and again if you donât completely eradicate the pest too. Also, because of all the hairy, waxy protection of the whiteflies, you can end up doing a better job of killing the predators than the pest, which seems to be the place your sister has gotten. 
>Â
>Interesting side note about the second ingredient: it has been given a RED assignment by the US EPA since 2005, and is under review right now- and illegal for commercial use while they asses its effect on endangered species. They already know acute exposure can have detrimental effects to childrenâs nervous systems. Under the wire, Bayer decided to put it in this homeowner product, presumably, because it is an effective broad spectrum Pyrethroid insecticide/miticide, and because they could.(They also stuck that last ingredient in there, a broad spectrum fungicide- which will kill beneficial fungi that break down organic matter as well as disease fungi.) Problem is- thereâs no current review underway for the effects of homeowner use. The review system isnât as foolproof as it should be. I would encourage your sister to give this product to her local household hazardous waste collector.
>Â
>I am attaching the pest management guidelines from the UC Integrated Pest Management program, and below is the link to the website page for management of all whiteflies. Notice that for each species, you can click on the name for a photo to use for ID. Those of you not familiar with the UC IPM website, should check it out; it is a fantastic resource for all kinds of pests, including weeds.
>http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7401.html
>Â
>Good luck to your sister, Kay. And try to discourage her using the Imidacloprid. Although it is an effective insecticide when used responsibly (such as in enclosed baits for ant control), because of its high usage as a systemic in flowering plants, it is now showing up in pollen and subsequently honey bee hives, and may be contributing to the colony collapse disorder. It should be a last resort to save high value plants, such as for show or commercial sales, but not your average rose bush or other flowering shrubs.
>Â
>Â
>Karrie Reid
>Environmental Horticulture Advisor
>UC Cooperative Extension, San Joaquin County
>http://ucanr.org/sites/sjcoeh/
>Â
>2101 Earhart Ave., Ste 200
>Stockton, CA 95206
>(209) 953-6109
>fax: (209) 953-6108
>Â
>-----Original Message-----
>From: medit-plants-request@ucdavis.edu
>[m*@ucdavis.edu] On Behalf Of Kay Dreher
>Sent: Sunday, June 09, 2013 4:34 PM
>To: Medit-Plants
>Subject: white fly
>Â
>Hello all,
>My sister lives in Glendora (southern California) and is having a white fly infestation. She's tried spraying them off with water as well as Bayer advanced spray (contains Imidacloprid, Tau-FLuvalinate, and Tebeconazole), which only seems to have made the problem worse. 
>Â
>All you in hot, dry climates: what can she do to kill the white flies but not the kitty cat?
>Â
>thanks in advance,
>Kay Dreher
>Berkeley, CA
>Â
>
>
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