Can anyone identify this growth on my Sweetgum (Liquidambar Styraciflua)?

[SilverShoe99]

This is the second season for these two sweetgums. I collected these seeds in the fall of 2018, cold-stratified them over that winter, and planted them in spring 2019.



I rotated their pot yesterday as I was watering and noticed a weird growth on the backside of the trunk that was further away from the sun.



Does anyone have any idea what this might be? I wonder if it's some kind of fungus, and my very limited knowledge of fungi tells me that when a tree has a fungal infection to the extent that it's producing fruiting bodies.....it's a real problem.

So...fungus? Maybe some kind of insect or other pest? If it is a fungus, do I need to be worried that it might spread to my other trees?

 

[Forsoothe!]

Looks like bark over a wound?

 

[Zach Smith]

Sweetgums produce wings on young branches like winged and cedar elms do. It's just a wing, and won't persist as the branch ages.

 

[SilverShoe99]

Thanks @Zach Smith. Did some googling for "sweetgum wings" and found a zillion images that look just like my tree.

I done learnt something new today

 

[Zach Smith]

They don't all do it every time, so when it happens you're a bit surprised. Not really a feature for a mature specimen, but an interesting thing that sometimes happens as the tree is growing out.