deer scaping on tree and damaging bark

Animal Repellents and Plant Protection

We all love animals but sometimes they go where we don’t want them to or damage our landscapes and gardens. They can chew, eat, scratch, and damage plants throughout the year. When animals get hungry, they may not spare much. Protecting your plant investment is about protecting them from extensive damage that will severely stress or kill your plant. If you end up with a few bites are scratches, luckily your plants will be fine and will heal. Very rarely do you see an unscathed plant in nature. They are tough and want to survive.

There are animal and human safe products available to repel mice, squirrels, voles, moles, raccoons, deer, rabbits…pretty much any animal you may encounter in MN.

First we will look at what animal damage looks like so you know what you’re dealing with if you see it.

What does animal damage look like?

rabbit clean-cut chew marks on a tree trunk
Rabbit chew marks on a tree.

The two most common animals that damage our plants are deer and small rodents like rabbits and voles. Deer will rub against the bark and leave gashes (see main post image). They will even chew off the top of shrub branches.

Rodent damage will have cleaner cuts. Rabbits can chew down into the cambium layer of shrubs and trees. The cambium layer is where water and nutrients are taken up. If the damage to the cambium layer goes around the entire branch or trunk, it will kill the plant. Voles can eat the roots of plants, bark, and dig tunnels that wreck lawn grass.

It’s important to reapply repellents as directed and after heavy snowfall. Make sure rabbits can’t get above the tree guards to nibble on the bark higher up the tree.

Scented Repellents

Various sprays and pelleted product contain scents and tastes that the animals are repelled by. The products contain all natural ingredients. They could contain clove oil, cayenne, peppermint oil, spearmint oil, putrefied egg, and possibly others. All of them are safe to use around your home and gardens.

Unfortunately, if animals are hungry enough, which can happen during harsh winters, they will eat despite any offending smells that typically keep them away.

Examples of a few animal repellents.

Animals can also get used to certain stinky smells. Alternate products that contain different ingredients to avoid them becoming used to the smell. Repellents will also need to be reapplied frequently and the frequency depends on the product instructions and weather.

Physical Barriers May Be the Best Bet in Extreme Cases

The use of physical barriers may be the best method in extreme and harsh winters or you have an abundant population of animals.

One common physical protection is a white plastic tree guard. They have two benefits. One is to prevent sun scald and frost cracks and the other is to protect tree bark from deer and rabbit damage. This is a great physical barrier to use every winter especially on young trees that have thin tender bark. There are also mesh plastic tree guards to put around tree trunks that can be used year-round as they provide adequate air flow around the trunk. Those will not prevent winter weather damage.

If it seems like deer and rabbits have already made your yard into a safe spot, you may have to start using repellents in combination with physical barriers on the perimeters of your yard to teach them it isn’t a good spot to feed and make a home.

White corrugated plastic tree guard.

What To Do After the Damage Is Done

As mentioned above, if rabbits or any animal chews around the cambium layer of a tree or shrub, the shrub branch or tree will die. All is not lost if you have still have part of the cambium layer.

In early spring you can prune off the branches of the shrubs that are dead. You can wait to see if leaves bud out before any pruning as well. If it doesn’t bud, it’ll be time to prune it off. If they didn’t damage all the branches, the shrub will survive. It may take a couple years to fill back in depending on the shrub and you may need to do selective pruning to reshape it.

In the case of a tree damage around the entire trunk, see if it leafs out in the spring and if it doesn’t, it is most likely dead or will die.

If you have an animal eat your herbaceous perennials in the early spring, they can recover if they didn’t eat them all the way to the ground. Even if they did, it still may survive if it’s in it’s active growing period and has a well-established root system. Another reason to make sure you properly water your new plants because the healthier they are, the more stress they can endure and survive.

Prune away branches that have bark damage around the entire branch.

Repel Mice and other Rodents from Nesting

You may have a barn, camper, boat, wood piles, sheds, decks etc. that you want to keep little critters like mice away during the winter and summer. There are repellents like Mouse Magic and Rat Magic that are safe to use around children and pets and won’t harm rodents or anything that eats them like some poisons do. They smell nice as well!

If you distribute the packs or granules around the areas that they may want to nest, along wall edges, and where they may enter, it should repel them away from those areas. If you have a lot of rodents, you may need to use more.

Rat Magic has a few more ingredients in it to help repel squirrels and chipmunks as well. Try sprinkling it around your garden if you have them digging up your bulbs or creating holes for their food stash.