hello. i'm a new member from iowa. i have a problem with my favorite tree and i need to get some advice so i figured this is the place to ask. thanks in advance for any help.
problem is my large american elm is splitting down the side because of how the tree has grown over the years. person who owned the place before me wasn't much for prunning his trees (this could have been avoided when the tree was young). anyway a cross branch has grown between two upright branches and is forceing the uprights apart creating a crack down the side of the tree. question is:

a. will cutting the cross branch out help my situation?.

b. can i cut the cross branch out without killing the tree. it's a big branch on a mature tree.

c. if i do cut the branch out should i stablize the upright branches with a chain or something in the hopes the crack will seal up?

i really hate to loose this tree. i realize it will be gone someday because of dutch elm desease but i want to hang on to it as long as i can. in the summer it is a really beutifull tree.

i've included some pics hope they show up. i'll be gone for a couple days but will check back.

i am at a loss as to what to do. i am concerned if i cut a branch that big i will kill the tree.

thanks for any help.