Looking on Harvey's map (Southern California LA area) there is a city every inch. Must be mostly concrete. - Millet

93 square miles.

It sure is heavily populated and not the kind of country I care to live in, but there are many homes with nice landscaping and I would imagine the area covered by the map contains tens of thousands of citrus trees.

So what will be done? Are they going to remove all citrus trees in this area?

From what I read in one of the articles somewhere (either posted in this thread or a CRFG Facebook post or a CRFG Yahoo group) was that the CDFA was going to seek approval from USDA (?) to spray individual trees yard to yard within close proximity of the discovery. I read that the origin of the diseased tree was being investigated to find if it may have been diseased when brought in or to start scouting for other diseased trees. I'm just guessing, but I think they'll probably tree every tree within 800 meters and then conduct a very heavy trapping program in the rest of the quarantine area as well as increase public awareness of the issue so that the public might cooperate and help keep an eye out for disease symptoms. Special funding from the USDA is being requested and a decision is expected in May or June (timely???), per http://westernfarmpress.com/blog/don-boxing-gloves-california-citrus-vs-hlb-fight?NL=WFP-01&Issue=WFP-01_20120404_WFP-01_110&YM_RID=harvey@chestnuts.us&YM_MID=1302835

The way so many people travel between LA and NorCal, visiting friends and family, it sure seems easy to see how this pest (and disease, possibly) could quickly jump several hundred miles.

I'm hoping that CDFA has learned from possible mistakes made in Florida and takes actions that might prevent the spread of this disease but I'm not naive enough to say that I am confident they will succeed. I'm probably slightly more optimistic than some of the most pessimistic of comments I've read in this thread.

What is the best control spray for the psyllid?

http://articles.latimes.com/2012/apr/08/local/la-me-citrus-disease-20120408

Millet it is a highly populated area, very dense. No open space hardly at all. For many, many, many miles. It is part of the larger Orange County/Los Angeles county metropolis. This is really going to be a serious problem. I think we'll see mass aerial sprayings as we did for the Mediterranean Fruit Fly. Since over 90% of citrus trees grown in the state of California are grown in a homeowner's back yard (UCR statistics shared during our Citrus in the Home Garden class through UCR Extension). This is what presents such a serious control/eradication issue. As the articles mention, commercial spraying is not a problem (and has been going on for some time). It is the management of home citrus that will cause HLB to spread in California. I can tell you that out of the 23 homes just in my little development, probably 22 of them have at least one citrus tree in their yard. Some many more like myself.

I have a nursery stock license (for activities other than my hobby citrus growing) and today I received a letter from CDFA. In short, they wrote that any citrus propagation must be done from mother trees maintained in screen houses effective 1/1/2013. Further, those trees must be tested for Citrus Tristeza Virus, Huanglonbing, Psorosis, and citrus viroids. The application and testing for this runs $200 plus $35 per mother tree ($30 for over 100 trees and $25 for over 300 trees). Testing is valid for 48 months.

Anyone who just maintains and sells citrus trees is exempt from the regulations so they are relying on testing of just the propagators.

If there is a breakout in HLB maybe this will make the nurseries a lot of money replacing trees that have died. How have nurseries done in Florida?

Harvey, I take it that propagators like Four Wind Growers, will have to build screen house structures if they wish to remain in the propagation business in California. BTW, I received an E-mail today from Joe Real through Linkedin, inviting me to "like" his site on Linkedin. - Millet (284 BO-)

I got one as well, but don't use Linkedin.

I'm not sure, but I think many California citrus nurseries have already built screen houses in anticipation of this coming. I remember reading about it a year or so ago in some ag publication I get. Duarte Nursery is greatly expanded citrus production and all of their production is in screen houses. If I recall correctly, that's something they made a point of mentioning when they had their annual open house almost two years ago.

In the past week I've picked up a Page mandarin and a Centennial kumquat at Costco grown at Willits & Newcomb. I just checked out their web site and a newsletter from last fall discussed their conversion to indoor growing: http://www.wncitrus.com/docs/Newsletter_Vol011_2011FALL.pdf

P.S. I don't use LinkedIn either. I still get invites but ignore them.

That's what I was told at UCR, too. All the large propagators/growers have screenhouses and their own budwood. I think the growers here in California have had the advantage of watching Florida struggle, and fortunately have taken serious steps in case the inevitable happened. And it has, now. So, it will be a matter of how to monitor all the backyard citrus here. I will be very interested to see what the plan will be.

"Maybe we'll be luckier this time."

http://www.latimes.com/news/local/la-me-citrus-disease-20120414,0,2096027.story