Mikawa Yatsubusa help!

[Basil911]

I’ve had my tree for about 5 months and the leaves are browning. I have 3 other Japanese Maples, different species on the property that are doing well.

 

[Pitoon]

Did you let it get bone dry? Looks stressed from not getting enough water.

 

[Mikecheck123]

How big is the pot? Looks about three sizes too big.

 

[Basil911]

Can the pot be too big? We were hoping it would grow a bit. The pot is 40” wide , the tree is about 3 1/2 ft tall.

 

[Basil911]

No it’s not bone dry. There is a drip line in the pot the soil is moist.

 

[Kanorin]

Did you let it get bone dry? Looks stressed from not getting enough water.

My first thought too. How much sun does it get each day? What climate are you in? (Update in your profile so you don't have to type this every post)
What kind of soil is it in?

 

[Mikecheck123]

Can the pot be too big?

It's the most common mistake. People think a big pot means faster growth, but that isn't true, particularly for JMs, which commonly suffer from pots that are too big.

A three foot tree should be in a one or three gallon container. 40" is much too wide.

I presume that it's also on a watering schedule that keeps the soil moist, which is also a problem.

If this were my tree, I'd carefully down pot into something just larger than the root ball. It's not a great time of year to be disturbing roots, but it's better than the alternative.

More info: https://www.evergreengardenworks.com/overpot.htm

 

[sorce]

Those walls will probably radiate a lot of heat too.

Looks congested and fungal to me.

Too wet.

Welcome to Crazy!

Sorce

 

[AlainK]

Looks congested (...) to me.

That's also what I think. A good proportion of lava rock (pozzolane) in the mix helps, more oxygen, healthier leaves. But I don't think there's any fungal problem.

You don't mention your location in your profile : knowing where you live could help for a better diagnosis. If you live in a place where there was a heat wave, + a compact soil, that could explain the symptoms.