Good Morning Rick, 

Thank you for contacting the U of M Extension Service. 

Here is a link from the U of M Extension Yard and Garden website about winter animal damage to the landscape: https://extension.umn.edu/yard-and-garden-news/winterizing-plants-animal-damage

This information discusses repellants to apply to trees and shrubs. 

Here is another link about managing voles and damage: https://extension.umn.edu/planting-and-growing-guides/vole-damage 

If you scroll down, there is information about using traps or pesticides to control them. 

Good Luck!