REQUIREMENTS
(ensure you have the requirements of the mods below as well)
Seasons of Skyrim For seasonal changes
Flora Additions - Willows For tree placements in the world
Willows - Improved Textures and LODs Tree appearance

Load my esp (flagged esl) after the above.

Willows sport vivid golden leaves in the fall and frost touched leaves in the winter.

I'm not really sure how to add snow to a tree so I just did some texture edits in photoshop. My wintery bark is photoshop noise. Not realistic but ... speckled white from blowing snow? We will go with that.

Also I didn't do anything in regard to LODs.

Works in my game. I hope it works for everyone else too :)