Author Topic: Avocado Laurel Wilt Question  (Read 953 times)

Julie

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Avocado Laurel Wilt Question
« on: January 13, 2022, 03:31:56 PM »
If I remove an avocado tree that does not have laurel wilt and do the stump grinding and then replant another avocado tree in the same place, could the remnants of the old tree increase the risk for laurel wilt?

Elopez2027@aol.com

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Re: Avocado Laurel Wilt Question
« Reply #1 on: January 13, 2022, 05:04:18 PM »
Yes, there is that probability. There will still be roots below after grinding. How much time between planting? Will you turn over the soil? It’s just a tough decision mixed with uncertainty.

GardenBoy

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Re: Avocado Laurel Wilt Question
« Reply #2 on: January 13, 2022, 06:57:37 PM »
To be safe, I would treat the suspected soil with an organic fungicide to ensure that any fungal spores in the soil are killed.  In fact, most biofungicides are actually beneficial to the soil by allowing the beneficial fungi, bacteria and other plant-symbiotic organisms to thrive while targeting and outcompeting the detrimental ones. You shouldn’t have any trouble finding organic fungicides online since there are quite a few of them to choose from. Also, applied at the first sign of leaf wilt, the trees root system may even be able to uptake enough of the fungicide to kill the fungal pathogens already present in the tree’s water system.

Galatians522

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Re: Avocado Laurel Wilt Question
« Reply #3 on: January 13, 2022, 10:58:40 PM »
Laurel Wilt occurs when a fungus carried by the Red Bay Beetle infects the cambium of the tree. Sick, wounded, flooded/overwatered, or dying trees emit a scent that is especially attractive to the beetle. They typically target branches of a specific size (arm to finger size as I recall). While the tree may emit an attractive scent for a short time after being ground, this will be end when the wood begins to rot. If you can't wait 6 months for the existing tree to start breaking down, buy one of the bags people have been growing citrus in and put it over the new tree. It should keep the Beetle out until the old tree is no longer producing an attractive scent.

Julie

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Re: Avocado Laurel Wilt Question
« Reply #4 on: January 14, 2022, 02:28:21 PM »
Laurel Wilt occurs when a fungus carried by the Red Bay Beetle infects the cambium of the tree. Sick, wounded, flooded/overwatered, or dying trees emit a scent that is especially attractive to the beetle. They typically target branches of a specific size (arm to finger size as I recall). While the tree may emit an attractive scent for a short time after being ground, this will be end when the wood begins to rot. If you can't wait 6 months for the existing tree to start breaking down, buy one of the bags people have been growing citrus in and put it over the new tree. It should keep the Beetle out until the old tree is no longer producing an attractive scent.

Thank you for your help.  It's definitely encouraging that the decaying tree won't attract the beetles after ~ 6 mo.

Galatians522

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Re: Avocado Laurel Wilt Question
« Reply #5 on: January 14, 2022, 10:11:51 PM »
The 6 month statement was just a guesstimate.  Apparently, the Laurel Wilt fungus can't survive longer than 2 days in wood chips that were initially infested with the disease. In contrast, a dead standing tree can continue to host the fungus for 15 months or longer. Logic would say that if the wood chips can't continue to host the fungus, they can't be an initial host, either. Here is a link to the research paper where I got the information.

https://www.google.com/url?sa=t&source=web&rct=j&url=https://academic.oup.com/jee/article/106/5/2093/878972&ved=2ahUKEwj93uuM2rL1AhV0QzABHefhC1oQFnoECAwQAQ&usg=AOvVaw1bPrVuBeWxV1z5LSj6oGZK

"Although not directly tested, this research indicates that R. lauricola would likely not move from wood chips to healthy trees if the wood chips were used in landscaping."

I think you are fine to grind the tree and re-plant. I would personally wait a few months, though, just to be safe.

CTMIAMI

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Re: Avocado Laurel Wilt Question
« Reply #6 on: January 15, 2022, 08:40:19 AM »
Julie, uninfected roots do not attract beetles.  Beetles like above ground trunk or branch material in trees that are struggling or weak for any reason.  These beetles are forest cleaners.   
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BQ McFry

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Re: Avocado Laurel Wilt Question
« Reply #7 on: January 15, 2022, 05:55:34 PM »
Having killed most of the Redbay trees, the beetles may be shifting to Sassafras as a host tree. There are reports of Laurel Wilt in Tennessee and Kentucky - so it takes more intense cold than temperate winters provide, to stop these beetles.

CTMIAMI

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Re: Avocado Laurel Wilt Question
« Reply #8 on: January 15, 2022, 06:07:03 PM »
These beetles, carriers are like miniature tanks. One day I had a tree being attacked by the Bettles and stomped the tree and painted the top with roof tar. Two days later dozens had drilled through the roof tar. 
Carlos
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