How to get rid of lichen? Bad case.

[Clicio]

I got this azalea Osakazuki from a japanese nursery whose owner passed away some time ago. It's an old tree, but I guess it was neglected for quite a few years, and the lichen got hold of most branches.
So, a toothbrush, water, vinegar and patience, or is the vinegar dangerous for the roots? Just in case the mix spills into the soil?

 

[bonsaichile]

A plastic brush maybe?

 

[Clicio]

A plastic brush maybe?

Yes.
Well, generally a toothbrush is plastic.
But the question is whether to use vinegar or not.

 

[Tieball]

Vinegar can work. I’ve removed Lichen before with just a hard bristle toothbrush when the Lichen is dry for a few days. Prior to removal with the brush I only watered the soil with no spraying of the foliage. Unfortunately some bark may be damaged slightly. Lichen imbeds itself into the bark. Example: Lichen on a shingled home roof is bad. The Lichen will dig a hole right through the asphalt shingle.

 

[River's Edge]

Get a hold of an old artists paint brush. I use one of my wife's approximately 1 cm wide at the base of the brush and a good point, Russian sable.
Vinegar and water 50:50.
This way there is less spillage and more direct contact than a toothbrush!
As you prune and cutback to redevelop the older tree the increased exposure of trunk and branches will assist in the cleanup as well. More sunlight.
Best of luck and have fun with the opportunity!

 

[fredman]

I usually spray vinegar...and brush it off few days later. Easy on the trunk, but fiddly between the branches...leaves don't like the vinegar.

 

[Dav4]

Vinegar for the win! I throw caution to the wind and just spray it straight onto whatever I want to kill… weeds, moss, lichen… safe and pretty effective.

 

[0soyoung]

I like lichen.
Lichens add to the look of age, IMHO.

 

[AJL]

The Vinegar treatment is potentially more dangerous to your Azalea than the lichen, which is not normally harmful and is an indication of clean air quality, so why do you want to kill it?

 

[Clicio]

I like lichen.
Lichens add to the look of age, IMHO.

I like it too, but in this plant it is effectively blocking new buds from developing.
Health comes first, so I think this is a good necessary solution, otherwise I risk losing the Satsuki.

 

[Dav4]

I like lichen.
Lichens add to the look of age, IMHO.

I love the look of Lichen on the craggy bark of an old tree… but when you see more lichen than bark, sometimes you gotta take action!

 

[Clicio]

The Vinegar treatment is potentially more dangerous to your Azalea than the lichen, which is not normally harmful and is an indication of clean air quality, so why do you want to kill it?

Please, could you make it clearer?
I know nothing about lichen, but I know new buds are getting to be really strong to sprout amidst the lichen, in this case.
So if they are not good for the tree, I prefer to get rid of them.

 

[Clicio]

I love the look of Lichen on the craggy bark of an old tree… but when you see more lichen than bark, sometimes you gotta take action!

This is my point of view too, @Dav4 .

 

[Clicio]

Someone, in another forum, mentioned that lime sulfur diluted by 5ml/l and sprayed directly on the bark, will kill the lichen and any insect eggs that are hiding under.
Is it effective?

 

[ShadyStump]

Vinegar should not hurt the tree significantly. It's often used as a stopgap soil acidifier while waiting for more long term measures to take effect.
I've used it successfully to help treat chlorosis in my gardenias when I discovered my soil mix was to alkaline. Unfortunately, I wasn't able to effect any long term solutions before they could be repotted, and lost a few, but it did help them take up their acid fertilizer more efficiently when I used it.
So it should be safe for azaleas.
If you're still worried, do the work before watering, then any vinegar in the soil can immediately be diluted with water.

I agree that as much as I like the lichen on trees, this is too much of a good thing, and needs taken care of.

 

[BonsaiDTLA]

you can try a diluted vinegar solution to see it’s effects. No harm in using less at first just to test it, only issue is that it isn’t strong enough to be effective

 

[Clicio]

Vinegar should not hurt...
...I've used it successfully to help treat chlorosis in my gardenias when I discovered my soil mix was to alkaline.

Applied directly on the soil, I guess.
I've heard some people saying that diluted vinegar is a good solution to lower the ph of the soil, but I believe a repot with the right mix for the tree is what really should solve this problem - of a too high ph.
Anyway I agree, if applied carefully with a brush, it shouldn't be an issue.

 

[Clicio]

Vinegar can work. I’ve removed Lichen before with just a hard bristle toothbrush when the Lichen is dry for a few days.

Thanks @Tieball , that's the plan.
Toothbrush, vinegar, and to be careful.

 

[Baku1875]

Thanks @Tieball , that's the plan.
Toothbrush, vinegar, and to be careful.

even with vinegar, be careful. small amounts of vinegar can do damage, especially to your roots.

After a quick search, maybe you should try diluted castilian soap and give it a good brushing and rinse a few days in a row

 

[0soyoung]

I'm always extolling the virtues of 300 ppm hydrogen peroxide as a broad spectrum fungicide (and antibacterial). It is maybe too late @Clicio, but lichen is an algae-fungi symbiont. Kill the fungus = kill the lichen (maybe add a few drops of detergent).