What are these raised red bumps on the top of my weeping willow leaves, and how do i get rid of them and prevent them from spreading to my other willows on my property?

Tammy - without a photo, I would have to guess that you are referring to a leaf gall, which is perfectly harmless to the tree. Here is an article from Ohio State University about all the galls that can appear on maples, to give you an idea: http://ohioline.osu.edu/factsheet/ENT-60 Specifically, on willows, I did find this short article with a photo, but can't vouch for the expertise of the writer: http://www.extension.uidaho.edu/nursery/Landscape%20problems/Willow%20Leaf%20Galls11.pdf Contact your Ohio Extension if you still have concerns!