Could you please send us a couple of photos of your tree both up close of the branches as well as from a distance to show the full tree.

Hi Marsha,

I would be glad to try to assist you with your question but I a little more information and some photos would be helpful. Could you please include a photo of the tree both up close of the effected branches and at a distance which would include nearby vegetation and the tree as a whole. Some other helpful information would be the variety of the tree, if you know it, and approximately how old it is.  When did you first begin noticing the rust coloring?  What direction does the tree face?  What was your watering schedule this fall?
I will reply as soon as possible after gathering more information to help you diagnose this problem.  

I am sorry to hear that your pine tree has some rusty needles and the top is dying. There can be several things that can cause this. Here is a link that might give you an indication of what's going on with photos of damaged trees that might look similar to yours. Without seeing the tree to diagnose the problem we would be guessing, so my recommendation is that you contact a certified arborist to diagnose the tree and recommend treatment. Here is a link that will help you locate an arborist that will come to your house to examine the tree: https://extension.umn.edu/planting-and-growing-guides/how-hire-tree-care-professional.
It is great that you are observant and want to get help for your tree. Since it has been with you for 25 years it is an investment that you want to retain.