Your pictures look a bit different but what do you think of this: https://blog.davey.com/why-are-there-brown-or-black-spots-on-my-maple-leaves/

first off.. its august.. in the midwest.. tree leaves get ugly.. but they fall off in a few months.. so 99.999% of the time.. nothing need be done about it..

never amend a planting hole.. well.. nest time anyway.. always use the native soil.. and dont amend the soil unless a soil test indicates what needs to be changed...

pull back the soil.. until you see the root flare.. and then show us...

https://duckduckgo.com/?t=ftsa&q=root+flare&iax=images&ia=images

imo.. just keep it properly watered.. and dont fix that witch isnt broken...

deep infrequent watering is the way to go.. and in mid to late november.. give it a good deep drink.. if the soil is very dry...

leaf damage in the heat of summer.. during the forst year or 3 after transplant is entirely normal... you dont compare you kids to the neighbors.. so dont compare you trees with long established trees in the area...

ken

ps: i just noticed the other day.. my variegated norway maple.. looks half burnt out.. so what.. every year fo re the last 20.. thats what is looks like in august... because of the variegation.. yours should settle in.. when it has a mature root mass.. to make it thru summer with little or no issues... there is nothing to do but wait.. for that mature root mass... tree time is counted in decades.. not months since planting....

Alot of wetness can promote fungal/bacterial infections on leaves. I doubt it's a serious problem as leaves are going to be falling in a couple months anyway.

Thank you so much.
Your advice is really valuable.

1. I agree, sprinkler watering is just not enough. Even for midwest, even after all that rain. Young trees need 2-3 gallons every week.

2. Am I supposed to mulch?

3. No comparing. This is a good advice. (I really appreciate).

4. As Ben pointed, I hope it’s just benign fungus.

Here is the root flare pic.

There's little I can add to the excellent advice others have gave unless it's to say for the future planting in Fall gives tree a head start over Spring planting.

I agree.

If the root flare is not level or slightly above the ground, the tree will not grow properly and show signs of ailments and decline as time goes on.

No gridding. Prior to planting I washed out and carefully removed root bound. I made sure most of the original soil is retained.

Do I need to mulch it? Some say yes n some people deny mulching. What is true?

I believe most trees whether newly planted or established benefit from mulch , with possible exception where soil is borderline overly wet. Mulch helps stabilize moisture variations between rain or watering. The pictures look like bed has ample compost/mulch. If your weather is hot and dry I suggest deep watering then don't water again until first sign of stress then water deep again. I believe the first sign in Maple is leaf edges starting to tilt vertical to sun.

Is your soil heavy clay?

Sometimes when people are planting in clay soil, they dig a hole then, as you did, fill, plant and finishing filling with compost/light soil mix - and unknowingly have created a tub where excess water sits around the roots, and also tends to discourage the roots from leaving that tub to grow into the surrounding soil. Which isn't good for the tree long-term.

raee I hear that alot on GW and I have heavy clay so it's time I try to understand how this works. I know from years of experience that few plants do well unless my heavy clay soil is heavily amended with compost. You told us what NOT to do,can you tell us what we SHOULD do?

Yes. I had heavy clay and concrete rock. I dug 3 feet in n wide. Sprayed Gypsum, filled water, checked drainage (took 30min).
I used Timberline top soil, mixed with a handful of pebbles, NO Compost or mulch. After a month, used 3 Miracle Grow fertilizer spikes 1 feet away from flare.

I am no expert, only know what I was taught and has worked for me.

It really depends on what you are planting - what that plant likes in its native habitat (like lots of moisture or not, lots of drainage or not, acid vs. alkaline). In general, a wide but not that deep of a hole - only as deep as the root ball - or less - with the clay broken up along the sides and bottom. Many trees will do better if the root ball is only 2/3-or 3/4 into the hole, but I wouldn't expect a maple to need that. Refill with mostly the native soil - some amendment is good, but you don't want to make a very different soil texture.

Klem1, I also greatly amended my planting beds except the area where I planned natives, because my yard had very poor drainage - standing water for hours after a moderate rain. I dug trenches about 2' deep, broke up the soil at the bottom with a fork, and refilled with a mix of the clay and any organic matter I had to hand - shredded paper, leaves, tree trimmings, straw, the grass clumps. Seems to have worked well, but I did learn that the sweet cherry tree was one of those that preferred to be planted higher.

Arjun, it seems that you did all that I was taught - I just wonder from your picture if the tree is planted a little too deeply.

The root flare is like 0.5 inch from the ground. I think it’s the heavy rains.
For the past few days it was very hot and now it seems like the wilted leaves are standing up. I’m keeping a close eye on new growth. Will report after a week.

I’ll water it tomorrow early morning.

Don't water on the basis of length of time between watering.

Check the soil and water only if the tree needs water and the soil is beginning to dry.

Rocks are not a good material to use for mulch. They heat up in the hot sun and hold heat for hours into the evening. Wood mulch is far superior and keeps the soil cool and also adds nutrients into the soil as it decomposes over time.

Best wishes on your tree. ;-)

bill