Tar spot and mystery plant
I have attached a photo of a sugar maple leaf. I'm wondering whether the spots on it are normal or if they are the tar spot or some other disease? I had tar spot on my red maple and was going to take these sugar maple leaves from a friend's yard to put on my garden, but I want to be sure my friend's leaves are not also infected. They are not as black as the spots on my leaves, but it's a different type of maple. Also, I have attached photos of two perennials in my garden. Originally I only had the one with the variegated leaves and it had yellow flowers and looked almost like a shrub. Then a few years ago another plant (or a different stage of the same plant) began appearing amongst this plant, also with yellow flowers but not variegated leaves. I'm wondering if the second one is a weed, a relative of the plant, or another stage of the same plant? The variegated leaf one wasn't as healthy this year as it used to be so I'm concerned that the other plant is harming it, but they look so similar I'm not sure what is going on. These photos were taken late fall so they didn't look this bad earlier in the summer.
St. Louis County Minnesota
I am sorry, I can't tell if the leaf in the photo has a fungal disease. Dead leaves just don't provide enough information. Usually with tar spot the center of the spot falls out because the tissue is dead.If you think the leaves are infected it really isn't worth the risk to put them on your garden.
In regards to the variegated leafed plant, variegated forms generally are less vigorous than the more common green forms. It is not unusual for a plant to revert and the more common type to take over. It is best to prune out the plainer green stalks if they appear.