AusBonsai

Hi,

Just wanted to know if there is any cause for concern with my Japanese Maple leaves turning white? Is this from a lack of nutrients, winds or too much sun? Thanks

I have not seen that particular pattern on leaves so can't be sure.
My first guess would be sunburn but that usually shows up as brown or black. If you see more damage on the sunny side of the tree suspect sunburn. How much sun does it get each day and morning or afternoon mostly?

Nutrient deficiency usually follows a pattern ie older leaves or younger leaves but this appears general all over the tree. Is there any reason to suspect nutrient deficiency? What's your fertilizer program like?

It gets sunlight mid morning to afternoon, mostly afternoon I'd say.

I've used fertilizer granules on the maple so I'm assuming this shouldn't be an issue with it being slow release.

The white colour is not prominent under the leaf, just the top.

A thought just occurred.....

How long have you had this tree? Is it possible this could be normal for this particular tree? Some JM have been selected because they have variegated leaves. Is the tree grafted?

It doesn't look like any sort of damage or nutrient deficiency, yellow patterns might but not white. I reckon you got a variegated plant or sport (spontaneous mutation) there. So you got yourself a wonderfully special unique JM. Note the white leaves lack chlorophyll, so won't be productive for the plant, which might mean a little more gentle treatment when trimming etc. Love it for what it is!

I've had this since March 21. It's a Katsura Japanese Maple, when I bought the tree, it didn't have the white colour in the leaves.

It's grafted as well.

It could still be a sport, new mutation, sometimes a plant will throw a branch of variegated stuff when it had no sign of it before. But it doesn't look unhealthy, and your fertilizer should be doing fine, so I wouldn't worry.

Seems like I've got something unique!

I'm also currently doing an airlayer on it, could that cause the discoloration?

Yeah, give it a name, but do watch fertilizer, maybe give it some supplement foliar feed just to be sure it is happy.

Thanks for your help

Layering does interrupt the sap paths and can occasionally affect the leaves. I'd guess that's most likely.
Mutation should not affect an entire tree so I doubt that's what this is.
Lets keep an eye on it and see what happens.

I've got a feeling it may be related to the layering too, we'll see with time.

You can get random mutations at any point in development. It it happens early, it can affect the whole organism symmetrically, but if it happens later, the mutation can be localised.
For example, some people have one green and one brown eye - one eye experienced a mutation during development that spared the other eye.
So if a mutation leading to variegation affected one branch, then that branch gets layered off and sold as a tree, the whole resultant tree that came about would have the same mutation throughout.
Just a thought! Not disagreeing with other opinions, just keeping alive the possibility that it’s a new variant…

Mutation sounds like a real possibility, I'll know for sure when we come to next year's growing season.

I have experienced loss in vigour in JM cultivars due to air layering, but not to this degree. More just less vigorous appearance and dull foliage, not complete bleaching.

Mutation is certainly a possibility