Anyone know what this is?

[Ming dynasty]

These are green Japanese maples. I’ve been trying to find out what this is but haven’t been able to. Tried googling, nothing in my book. I see these black tar like spots on the trunk. I was able to scratch it off. Just making sure it’s not the wilt disease. Lmk if you experienced this or know what may cause it. Thank you.

 

[Paradox]

Didn't you say in another thread that you've been having high humidity?

It could be just mold if you were able to scratch it off. Take a wet rag and clean it off the trunks and see if it comes back

 

[Ming dynasty]

Didn't you say in another thread that you've been having high humidity?

It could be just mold if you were able to scratch it off. Take a wet rag and clean it off the trunks and see if it comes back

Thank you y’all, I live in Georgia and it’s typically pretty humid in summer. For mildew irs best to get air flow and sun exposure?

 

[penumbra]

Thank you y’all, I live in Georgia and it’s typically pretty humid in summer. For mildew irs best to get air flow and sun exposure?

Yes.

 

[Dav4]

I know that stuff... Georgia Gradoo! Way high humidity with frequent afternoon showers and mold will grow on anything. It's truthfully only bothering you and not the plants. Good air circulation will help as will more sun, and you can wipe it off with a towel. White vinegar sprayed directly on it will probably kill it, too... but it'll be back in August... and September...

 

[penumbra]

Wipe it off and spray with peroxide / water, 50/50.

 

[Ming dynasty]

I know that stuff... Georgia Gradoo! Way high humidity with frequent afternoon showers and mold will grow on anything. It's truthfully only bothering you and not the plants. Good air circulation will help as will more sun, and you can wipe it off with a towel. White vinegar sprayed directly on it will probably kill it, too... but it'll be back in August... and September...

I saw somewhere said vinegar can be deadly for plants

 

[Ming dynasty]

Wipe it off and spray with peroxide / water, 50/50.

May just leave it alone if not affecting plants. Already hitting them with pesticides and fungicide

 

[Dav4]

I saw somewhere said vinegar can be deadly for plants

Horticultural vinegar- 30% + acetic acid- is a landscape herbicide. White vinegar- 5% acetic acid- is used as a household cleaner. I wouldn't dump a cup of the stuff into your pot soil, but I've used it as a spray to kill weeds in the pot or get rid of moss or algae growing on the trunk. I used to dilute it by half with water but use it straight now... no issues.

 

[penumbra]

Peroxide is produced by mushrooms to kill spors of other invading mushrooms. I use it almost daily and have not had any negative effects.