[Red/FL-swamp Maple] My Maple's new growth looks terrible after a recent, minor defoliation & I cannot figure out why :(

[SU2]

I'd say "wet feet" if I didn't know this thing grew-up in standing-water (it's a swamp-Red Maple), that's how the leaves looked early this week they got better* but it still shows here today/now:
pic where I circled two spots, sorry but this thing's photo-editor menu didn't pop-up so it's just black line

[made the black-lined rectangles/squares around the two spots 'bold enough' I hope, one's dead center the other's to it's 1 o'clock]

Here's me holding a branch, this is how it was throughout the tree earlier this week with almost all of the new growth taking-on that "wet feet" blackened mottling of the leaves (you can see some on the tip of this branch, as well as at a secondary branch's tip that originates off this branch:


It gets full sun til 2:30p -ish, then indirect....used to get more & loved it though... I do 3-->4x/day irrigation but my other maple (also collected 2yr ago) is thriving and not even getting as much light....

Part of me worries it could be a combination of two things I'd been "working towards",
#1 Anytime branches got too-long I'd either remove the final-leader of the branch(leaving a new growing-tip, kinda "clip&grow as-needed" for space reasons), and I also would defoliate those big giant leaves that Maples tend to keep on the nodes where they've shot a secondary branch, defoliating those would always give awesome backbudding/ramification growth and I'd done a rather aggressive session of this in the past weeks..

#2 Roots/base...I've only barely put thought into this guy's canopy, just 'formal-ish upright', have been in-love-with & working his base:

^I pulled-back those marble(non-porous) rocks for this pic, BUT this top-dressing of non-porous marble along the nebari, and a mix of tan sphagnum & myco-mulch as "top-dressing" for the rest of the surface, is new I mean like I put it in-place earlier this week in-hopes it would help out...cannot tell if its recovery has been aided by that or not, *but* earlier this week I'd seen a lil branchlet sprouting out from so low on the trunk it was nearly soil-level, I rarely see that behavior on happy/healthy trees, part of me wonders if I'd pushed it too-hard by denying it any top-dressing(and actually keeping substrate very low-height) and then doing the partial defoliation(only of the larger/mature leaves), perhaps it was too big a shock? Have done more to Maples but maybe he just wasn't up for it this time?

Thanks for any thoughts/advice on this guy, his trunk is one of my favorites

PS- I think I can comfortably rule-out some things:
- nutes: I've had him on low fert for while (gets too leggy otherwise), so cannot fathom over-fert nor could deficiencies be a problem with such an organic mixture as he is in (or so I'd think....also he's been in this pot since early this year)
- pH: I use rainwater and, when using hose water, I'll blast the trees with the hose and then water by-hand with a pH corrected solution (phosphoric acid/"pH Down")
- water: he's from standing-water....so too-much is hard to think of, and too-little definitely didn't happen!!

Again thanks a ton for any advice, I've gone and removed some wiring just to increase tissue/cambial efficacy but would really like to diagnose this!!

 

[Forrestford]

The direct sun may to too intense for the new growth. I suggest putting it in a shadier spot and see if that affects your new growth. If you have to water it 3-4 times a day its probably getting scorched by the sun.

 

[SU2]

The direct sun may to too intense for the new growth. I suggest putting it in a shadier spot and see if that affects your new growth. If you have to water it 3-4 times a day its probably getting scorched by the sun.

That's how sun-damage looks? I wouldn't have guessed that, kinda thought the Maples were bullet-proof to that!!

It's FL so that's just the default though.. and FWIW I don't need to irrigate that much, in FL there's a midday "wilting/lull" in most species, for instance a bougie's leaves will look a lil wilted even when the soil's moist, if the sun is very intense (which is the norm through our summers), over the years I've found that the midday waterings seem to negate this "midday dormancy/napping" and have seen much more growth (actually it was nearly 2yr ago that I'd finally began dropping fertilizer a bit because of too-much growth, couldn't keep up with it & the insects were too-fond of the supple new tissue so scaled it back!)

Will move it to a shadier spot, going to temporarily put my other, healthy maple in its place to see if it goes downhill at all (because I suspect moving the other, healthy maple to that spot will help it, but we'll see! IF it does, it's likely that the defoliation & low substrate level caused this thread's Maple to be intolerant of the high heat!

 

[Leo in N E Illinois]

Take a sheet of plain white, gray or brown paper with you and use it as background. Can not make sense of any of your photos. Can not see what you are worried about, it is all a jumble of green.