Plastic tree guards - Ask Extension
I have many1-3 year old plum, maple and oak trees-all protected with white plastic guards of 2 or 3 foot lengths, which I have been leaving on through...
Knowledgebase
Plastic tree guards #927680
Asked April 06, 2026, 4:41 PM EDT
I have many1-3 year old plum, maple and oak trees-all protected with white plastic guards of 2 or 3 foot lengths, which I have been leaving on throughout the year. Some publications suggest removing except for the winter months- rabbits seem to do the most damage although deer may also be eating the bark of these young trees. Am I causing more harm by leaving the guards on continuously?
Hennepin County Minnesota
Expert Response
Yes - it's best to remove the guards during the growing season, from about April through November. This prevents mold or fungus growing between the guard and the tree trunk and allows bark to naturally harden. It also eliminates a closed location where insects could congregate and you won't have to worry about the guard digging into the bark itself. If deer are the primary problem, reinstall the guards in early rather than late fall to protect the trees against browsing. For more information, see https://trees.umn.edu/sites/trees.umn.edu/files/files/media/stem_protection_fact_sheet_0.pdf
