I have two native hawthornes that get the disease (some years worse than others) but they're really never any issue beyond having the spots.

This year I noticed my Serviceberry and Coralburst Crab have traces of rust, not too worried but my Crusader Hawthorne has many fruit with spiny spore all over them...but the leaves look fairly clean.

Would you pull and dispose the fruit or leave it?

Also do you folks ever treat for rust diseases?

I'm thinking I should only treat if I'm having defoliation issues.

None of my junipers or cedars have galls and my neighbors don't have any so obviously the host is beyond my control.