Help Identifying My Japanese Maple's Issue

[MWGH]

Hi Guys.
First post to the forum, looking for some help regarding what I suspect is a fungal disease on two of my Japanese Maples. The symptoms are identical on each tree.
Because I lack the experience and knowledge most members of the community here have, I was hoping to get some advice into possible remedies before doing anything too drastic.
Leaves are distorting, browning and dying off, especially new growth. I have also noticed some white patches on leaves. The pictures below will tell a better story.

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Any advice you can give would be much appreciated!

[KIRKY]

It looks like leaf scorch to me. Can you advise where it is in the yard full sun,shade,windy? etc...
you can get leaf scorch from trees being exposed to high/hot winds, hot sun we just had out first hot day for the season. It can also be caused by underwatering. The more info you can give the easier it will be to determine what may have happened.
Cheers
Kirky

[MWGH]

The trees are in full sun until about 3pm when they fall under shade, so leaf scorch is possible. Relatively sheltered yard as far as wind is concerned.
It's been relatively cool in Melbourne thus far which leads me to believe it's another issue, as I first started noticing it two or three weeks ago.
I'll try moving them into a shadier spot and hope it helps.

[Akhi]

agree with Kirky. Also don't get any water on the leaves on a sunny day

[KIRKY]

The hot North wind we had recently. And the 35-38 the other week would have been enough to cause this. Especially if it was on the dry side. Maple are sensitive and it doesn't take long for them to show stress.
Cheers
Kirky

[MWGH]

I've definitely been guilty of watering the leaves on hot days, something I didn't realise was bad practice!
Thanks for the info guys.

[KIRKY]

I have watered the leaves of all my trees on hot day with no ill effects. I don't believe that ths s the problem.
Cheers
Kirky

[MWGH]

What kind of preventative measures do you take for your trees Kirky? My understanding is JM like to be in full sun? Would you recommend I move them somewhere they're more sheltered after midday when the sun is at it's most intense?
I keep my trees well watered so I don't think drying out in the roots would be an issue. I was actually worried it could be root rot, despite how well draining their soil is.

Sorry to keep pestering you with questions. I'd be upset if I lost these guys!

[kcpoole]

I have watered the leaves of all my trees on hot day with no ill effects. I don't believe that ths s the problem.
Cheers
Kirky

I also think there is no issue doing that. I suspect it is an old wives tale myself
Ken

[KIRKY]

I have Maples in large pots as well as bonsai's. Only ever lost 3 Maples trees in the ground/garden The large terracotta pots are in full sun all day. Only on days over 38-40 degrees do I get leaf burn on these larger trees. However, the hot Northerlies we get can knock the leaves about.
The bonsai's however are in full morning to mid afternoon say until 2pm. With no problems. They are however sheltered from the Northerly winds. As for treatment I do a 50/50 Seasol/Powerfeed. Seasol for celular stress roots/leaves etc...
They also get Seamungus pellets when I remember to refill the little baskets.
Cheers
Krky

[Firecat]

The hot North wind we had recently. And the 35-38 the other week would have been enough to cause this. Especially if it was on the dry side. Maple are sensitive and it doesn't take long for them to show stress.
Cheers
Kirky

Exactly.
I had 3 English Elms that have been going fantastic.
That one out of the box hotty where I was out and to my disgust had folded back my shade roof a week before to get the most out of the duller sunlight poached the ends.
No curl or withering initially, just sent the leaves karki..boiled and cooked.
Good idea now to do a defoliation and reap the spectacular re growth.
Not the 'hand of death ' for your Maple I'm sure.
Steve.

[MWGH]

Thanks for the replies!
Although I read as much information as I can get my hands on, there's still some things you can only learn with time and experience. Luckily I have this forum to turn to.