Rust fungus I think.

is there any impact on the plant ... can we have a pic without your hand???

if its all in the soil ... ignore ... rough up the soil .. let it dry ...

usually fungi is working on mulch/wood/compost ..... i cant tell how much wood is in or on your soil ...

its fall .. it will be going dormant.. i wouldnt be too concerned...

if you feel you must take action.. dig it up.. and throw it on the driveway for winter.. it should be fine .. lol

ken

Thank you both. It is only on the soil under this hosta only. There is no mulch. The hosta is very full and looks great. I will look up Rust Fungus. I don't think it gets any light or air under there because it is so thick and down to the ground....maybe some fungus has taken to the soil. It might fix itself as you say if I cut the leaves down when the season ends and rough up the soil. I might even divide it next spring thin it out and open it up a bit.

that's what fungi like: dark and moist (think athlete's foot)

i have glacial sand.. think beach ...

you have a very black.. humus filled soil ... including wood pieces i can see ... thats is what the fungus is working on ... organic material ...

if you have a 3 prong hand rake.. just lightly rough it up now ... gently ... if you dont have one.. its a great tool to invest in ..

ken

https://www.google.com/#q=3+prong+hand+rake