help white stuff on oak leaves

[winona1]

help I keep getting this white stuff on my oak leaves do you know what it is picture attached

[hkspowers]

looks like a type of lichen. Not sure though. How do u prepare your leaves before you put them in your tanks?

[kleinhanz]

1) those are funny looking oak leaves, did you collect them or did you purchase them?

2) Did the leaves have the white spots when you first obtained them? If not, it is not lichen. I would peg it for mold and in most cases it is nothing to worry about.

[DartFrog]

It looks like the vein structures of the leaf are spared and the rest may have been eaten by something. I dont think either way it is anything to be too concerned about.

Mike

[13013]

try and wipe it off with a finger, if it comes clean, worry... although trichoderma looks pretty similar, and is beneficial.

[boyer420z]

This fungus is transferrable to other plants. Excess water on the plant's surface can kill spores and inhibit growth of mycelia, and both spores and mycelia are sensitive to extreme heat and direct sunlight. Control of powdery mildew can be difficult, but there are fungicides that can be used. Neem oil, triadimefon (Bayleton, Fung-away), triforine (Funginex), and chlorothalonil (Daconil) are some of the fungicides labeled for powdery mildew control. This would be ideal for treating an orchard, but I would suggest removing the leaves.

[13013]

bacillus subtilis would kill it without affecting anything else, it's rather specific.
serenade is one product i would reccomend... OMRI certified, and again, rather specific, neem is a great preventative, but i've never seen it cure powdery mildew, and i don't understand the action/actives of the other fungicides mentioned, so couldn't say how they'd react around anything but plants... beauty of B. subtilis, from what i understand, is that it only attacks pathogenic fungi, so it won't kill any beneficials you may have loving it there...