The Tropical Fruit Forum

Tropical Fruit => Tropical Fruit Discussion => Topic started by: C24mccain on January 16, 2019, 05:50:14 PM

Title: White patches on avocado branches?
Post by: C24mccain on January 16, 2019, 05:50:14 PM
Can anyone tell me what this white stuff is in these pics on my mexicola avocado tree? I'm getting a few small branches dying as well and this stuff seems to be on those dead twigs fairly often but not always.


(https://i.postimg.cc/QBfL2K12/IMG-20190116-171136862.jpg) (https://postimg.cc/QBfL2K12)

(https://i.postimg.cc/gwzFtHXy/IMG-20190116-171155449.jpg) (https://postimg.cc/gwzFtHXy)

(https://i.postimg.cc/vgDRb8vc/IMG-20190116-171210895.jpg) (https://postimg.cc/vgDRb8vc)

(https://i.postimg.cc/gxqbKTJk/IMG-20190116-171251526.jpg) (https://postimg.cc/gxqbKTJk)

(https://i.postimg.cc/hh6n4m6g/IMG-20190116-171340779.jpg) (https://postimg.cc/hh6n4m6g)
Title: Re: White patches on avocado branches?
Post by: MangoCountry on January 16, 2019, 06:22:50 PM
Possibly lichen. Harmless if so
Title: Re: White patches on avocado branches?
Post by: Dangermouse01 on January 16, 2019, 07:18:48 PM
Lightly spray with water and see if there are any soft body insect things under it. Kind of looks like mealy bugs or some type of scale.
Title: Re: White patches on avocado branches?
Post by: Jack, Nipomo on January 16, 2019, 10:17:39 PM
Looks like dried avocado sap indicating an injury (mechanical or insect).
Title: Re: White patches on avocado branches?
Post by: Mark in Texas on January 17, 2019, 10:05:44 AM
Some kind of disease.  Doesn't quite look like mealybugs.

http://ipm.ucanr.edu/PMG/r8100611.html (http://ipm.ucanr.edu/PMG/r8100611.html)
Title: Re: White patches on avocado branches?
Post by: C24mccain on January 17, 2019, 07:20:06 PM
Some kind of disease.  Doesn't quite look like mealybugs.

http://ipm.ucanr.edu/PMG/r8100611.html (http://ipm.ucanr.edu/PMG/r8100611.html)

Thanks Mark I'm pretty positive this is my issue. It's minor at the moment so I'll monitor it.
Title: Re: White patches on avocado branches?
Post by: achetadomestica on January 17, 2019, 09:29:40 PM
Copper fungicide?
Try one infected area as an experiment. I have seen something similar on citrus and
even peach trees. I experimented last year and the copper worked?
Title: Re: White patches on avocado branches?
Post by: PahoaJo on January 20, 2019, 01:37:09 AM
Do you see any borer holes, like the size of a pin hole, that the white stuff is surrounding?
Title: Re: White patches on avocado branches?
Post by: C24mccain on January 20, 2019, 07:09:08 AM
Do you see any borer holes, like the size of a pin hole, that the white stuff is surrounding?

I have not seen any but I do know there is a tiny black mite that hits the leaves, often in the center of the leaf leaving a brown spot on the leaf.
Title: Re: White patches on avocado branches?
Post by: Coach62 on January 20, 2019, 11:35:02 AM
Some kind of disease.  Doesn't quite look like mealybugs.

http://ipm.ucanr.edu/PMG/r8100611.html (http://ipm.ucanr.edu/PMG/r8100611.html)

Thanks Mark I'm pretty positive this is my issue. It's minor at the moment so I'll monitor it.

My Mexicola has had the same issue for 2years, must be susceptible to it. Probably will pull it and replace after this next crop. The fruit is just so-so anyway.
Title: Re: White patches on avocado branches?
Post by: Guanabanus on January 20, 2019, 09:41:11 PM
Not a clear enough image, but it is probably meally bug.  Blast it off with a garden-hose pistol, and repeat 3 or 4 times at about 5-day intervals, then finish up with an oil spray, following label directions about dosing and mixing--- and maintain agitation,
Title: Re: White patches on avocado branches?
Post by: spaugh on January 20, 2019, 09:51:55 PM
Its the sap of the tree like Jack said.