Greening... argh... do I KILL them all?

[MassSpectrum]

I have 17 different citrus cultivars. Been growing them in big pots for a few years each now. I'm pretty sure at least a couple got greening, but no signs on my Everbearing Keylime or Calamondin. I figure most the rest all complex/interspecies hybrids, some real nice stuff like Blood Orange, some different variegated lemons/limes. A shame to just start nuking them, but same time I'm done screwing around and need to KILL this damned disease from my realm. A lot of them were in my old 'jungle' grow out yard design I used to run in the yard, when it was all still just hobby, all mixed up stuff a lot of stuff got smothered including most the citrus. A lot of them, most of them had rooted into the ground it took weeks of chopping roots and trimming stuff way back as also needed to be cutting such roots etc. Trying to put all the big stuff off site, to grow out here mostly only the little plants I mail order. But he's got (unspected) citrus over there too (including wild stuff a couple generations old from the hybrid porrage soup, running off into the woods behind there. Yeah, complicated.

Any insights about how to approach this cluster-f would be wildly appreciated.

[ericalynne]

As far as I can tell, searching on "greening" no one has answered this question. I am wondering what others are doing in their backyard orchards.

I have a dancy tangerine that is obviously seriously infected with classic symptoms, including bitter fruit. Also a couple of lemon and a couple of orange trees that look like they probably have early stages. Then I have a finger lime, kept in a separate location that does not seem to be infected at all. It is still in a large pot.

Do I:

1) Tear out all the citrus (except the finger lime)
2) Remove the Dancy and keep everything else
3) Keep everything and do a lot of foliar spraying to keep them as healthy as possible.

There are commercial orange orchards about 2 miles away. If I cleared it all out, would I be likely to be reinfected?

Erica
Venus, zone 9b

[Millet]

If your sure the tree has greening then there is no cure , at least at this point in time.  For the sake of your other trees and your neighbors trees you should get rid of the infected trees. In the state of Florida every citrus growing county is infected with greening. = Millet

[ericalynne]

I understand the concept of removing infected trees. Florida did that for citrus canker and found it was not useful and a lot of good trees were destroyed with no effect.

The reason I mentioned the nearby citrus grove is because I am wondering if I would get re-infected with the greening if I replanted new citrus. For that matter, I don't know if there is a way to distinguish greening free trees for purchase or not.

The two miles between me and the citrus orchard are native woods and cow pastures. I am wondering how far those little psyllids can fly.

In Florida, the advice most commonly given to home orchards is to just use a lot of foliar spay and keep the trees as health as possible. I was wondering what others on the forum have done.

Erica

[Jsvand5]

I understand the concept of removing infected trees. Florida did that for citrus canker and found it was not useful and a lot of good trees were destroyed with no effect.

The reason I mentioned the nearby citrus grove is because I am wondering if I would get re-infected with the greening if I replanted new citrus. For that matter, I don't know if there is a way to distinguish greening free trees for purchase or not.

The two miles between me and the citrus orchard are native woods and cow pastures. I am wondering how far those little psyllids can fly.

In Florida, the advice most commonly given to home orchards is to just use a lot of foliar spay and keep the trees as health as possible. I was wondering what others on the forum have done.

Erica

Yes, if you replant the new trees will get greening at some point. When you buy the trees they should be clear because they are propagated in a screen house as far as I know. They will get infected though. Just a matter of time.

[Millet]

 When canker struck Florida, the thought was to remove all the trees diseased with canker to limit the possibility of the disease from spreading.  However, the hurricane (was it Andrew?) came along and the storm's winds and rain spread canker everywhere the storm went.   After the hurricane, the tree removal was stopped, as its original purpose was no longer viable.  - Millet

[KarenRei]

Old thread, but it's worth mentioning that there actually is one treatment for greening which seems to be effective:

http://www.ars.usda.gov/is/AR/archive/aug13/citrus0813.htm

Seems to put greening into remission, and possibly even in some cases cure it.  And it's not just about hiding the symptoms, it actually seems to kill bacteria or otherwise interfere with the infection, although the exact process is still unknown.

[Millet]

Ricke Kress is president of U.S. Sugar's Southern Gardens Citrus in Clewiston, FL. the largest grower in the state. Southern Gardens Citrus has spent millions of dollars on research, Kress said, and he is skeptical that fixes such as heat exposure offer a long-term solution.

"We have 1.8 million trees," he said. "When you have some time over the weekend, you can help us tent them, okay?" 

If it took 4 minutes per tree to treat a tree with the steam method, it would take about 15,000  eight hour work days to treat this one orchard a little over 4 years. - Millet

At

[Tropheus76]

Which is why I have been saying the bag treatment was for once a treatment better for the courtyard grower rather than an industry treatment. We don't get lucky like that very often. Usually all the fixes go to the big boys.

[KarenRei]

Ricke Kress is president of U.S. Sugar's Southern Gardens Citrus in Clewiston, FL. the largest grower in the state. Southern Gardens Citrus has spent millions of dollars on research, Kress said, and he is skeptical that fixes such as heat exposure offer a long-term solution.

"We have 1.8 million trees," he said. "When you have some time over the weekend, you can help us tent them, okay?" 

If it took 4 minutes per tree to treat a tree with the steam method, it would take about 15,000  eight hour work days to treat this one orchard a little over 4 years. - Millet

At

Then they're not very creative. Don't bag each tree, just drag a giant (multi-acre-sized) sheet of cable-reinforced plastic across your land, moving it 1/7th of its length every day, and covering the full acreage over the course of the year. Then you don't have a per-tree labor cost. All that matters is heating the trees, it doesn't matter how you do it.

(Yeah, a giant sheet of cable-reinforced plastic would be expensive. But you know what, so is citrus greening of 1.8 million trees. Your plastic will last several years and you can make money from recycling it when you're done)

[Tropheus76]

And as a side use, you can use it to cover the orchard when it gets freezing.

[KarenRei]

And as a side use, you can use it to cover the orchard when it gets freezing.

That too! 

[Millet]

The larger an area that is covered by a curtain, the more difficult it becomes to raise the heat level to the point of killing the bacteria of greening.   It would VERY soon become impossible. - Millet

[davidgarcia899]

Idk if anyone else is having this experience, I am not even sure if I have greening, but ive notice that my ungrafted citrus, i.e. seed grown citrus is doing very well. So I'm tearing out all my grafted citrus and replacing it with seed grown stuff, I know most wont come out true to type, but w.e.

[Millet]

 Davidgarcia, fortunately almost all citrus varieties do come true from seed. Meyer Lemon, Pummelos, the King Mandarin, Clementines and Temple  do not produce true from seed.  Know that seed grown citrus are just as susceptible to Greening as are grafted trees. - Millet

[davidgarcia899]

Davidgarcia, fortunately almost all citrus varieties do come true from seed. Meyer Lemon, Pummelos, the King Mandarin, Clementines and Temple  do not produce true from seed.  Know that seed grown citrus are just as susceptible to Greening as are grafted trees. - Millet

I am planting several of those you listed, also my seed is coming from trees planted at 8 ft spacing so I think there is chance they have cross pollinated.

I know that seed grown is supposed to be just as susceptible, but at least so far, my healthy trees are on there own roots. I dont know if i have greening, Ive always suspected that trifoliate orange is a bad root stock for my soil, and my trees that are most rapidly declining are on trifoliate

[KarenRei]

The larger an area that is covered by a curtain, the more difficult it becomes to raise the heat level to the point of killing the bacteria of greening.   It would VERY soon become impossible. - Millet

Where are you getting that? It's precisely the opposite. The larger the curtain the less heat will escape around the sides relative to the total heat flux (which scales linearly with area, as sunlight scales linearly with area). Perimeters scale linearly while areas scale quadratically.