In many parts of the United States, winter is a time when perennials enter dormancy to generate themselves for the next spring's new growth. Deciduous trees and shrubs simply lose their leaves, and other foliage and flowering plants may die down. While heavy layers of mulch or snow may provide some measure of underground protection, these plants still face the threat of damage, if not total destruction from various forms of wildlife. Different types of wildlife pose a threat to homeowners in different parts of the country.
A growing population of deer and rabbits are posing greater threats to people in urban communities. Unable to find food in the wild, these creatures are forced to seek it wherever they can, and that often means your perennials, trees, and shrubs become an attractive source of food for them. The presence of fallen bird seed is another thing that appeals to starving critters.
This guide is designed to provide some help to those who face the problem of garden destruction from three types of animals that do a considerable amount of damage to gardens during winter: voles, deer and rabbits.

Voles

Voles are active around the clock and all year. They are small rodents with tiny eyes and small ears. These members of the Microtus genus are characterized by short and stocky bodies, short legs, predominately short tails, and bodies that are mostly brown or gray, or a mixture of colors.
Because they are underground creatures, most of their activity consists of underground burrowing. They build underground tunnels and they travel through the tunnels to forage for food. Homeowners don't become aware of their presence until their surface runways are visible, and that takes a long time. By then, they've wreaked havoc on underground plant roots, bulbs and tubers by eating away at them.
Voles are also known as field or meadow mice. Although there are 23 species in the United States, seven species are widespread and are known for causing the most extensive damage. They differ from moles in that voles eat only vegetation, whereas moles also eat bugs.
  1. Prairie Vole - (Microtus ochrogaster) found in Great Plains, grasslands, including grassy prairies and marshland. It typically measures about 5 to 7 inches from the tip of its nose to the tip of its tail. It is gray to dark brown.
  2. Meadow Vole (M. pennsylvanicus) commonly found in the northern United States and Canada, its preferred habitats are grassland areas and wet meadows. It measures between 5 1/2 and 7 1/2 inches in length. Meadow voles found in the U.S. are typically yellowish-brown to gray, with black-tipped guard hairs. Northern species that are found in extreme northern part of the United States and in Canadian provinces are more likely to have red-colored fur.
  3. Long-Tailed Vole (M. longicaudus) Most likely to be found in Canada and throughout the western part of the United States, the long-tailed vole lives along the banks of streams, in forests, meadows, on mountains and in sage bush grasslands. It is very easy to distinguish from other vole species because its tail makes up 30% - if not more, of its total body length. It is a larger species, measuring between 6 and 8 1/2 inches. It is dark-brown to gray in color and its fur is mottled with black-tipped guard hairs.
  4. Pine or Woodland Vole (M. pinetorium) the pine vole is widespread throughout the eastern United States. It prefers to live in deciduous area, including pine forests, orchards, and open, neglected, and abandoned fields. It is very small compared to other vole species, measuring only 4 to 6 inches. It has dense brown fur.
  5. Montane or Mountain Vole (M. montanus) the mountain vole is found in the mountainous areas of the western United States. Its preferred habitat is sage brush grasslands, dry grassland areas, and mountain meadows. It measures between 5 1/2 and 8 1/2 inches, and has brown fur; mixed with gray and yellow, and black-tipped guard hairs.
  6. Oregon Vole (M. oregani) The Oregon vole lives in forests and burned grassy or brushy areas of the Pacific Northwest, including Northern California, Oregon and Washington. It prefers areas that are clearer - like those that may be covered with leftover debris from wildfires. This gray or brown species measures 5 1/2 to 6 1/2 inches in length.
  7. California Vole (M. californicus) The California vole prefers shrub land and chaparral woodlands in California. It is equally happy living in well-drained or wet areas. This larger vole species measures 6 to 8 1/2 inches in length. It is a reddish, cinnamon brown - to a tawny-olive green. As with other vole species, it also has blackish brown-tipped guard hairs.

Prevention

1. Disrupting the Habitat
  • Any buildup of weeds or excess vegetation, including ground covers will create the perfect hiding place for voles.
  • Rid the area of weeds
  • Keep the ground exposed - to the extent possible
  • Don't plant ground covers around the base of plants, trees or shrubs
  • Be sure you keep grass mowed to a reasonably low height
  • Rake all leaves and remove grass after mowing.
2. Create Barriers to Protect Trees, Shrubs and Plants
Cylinders of hardware cloth or mesh are very effective at creating a barrier that voles won't be able to cross - around individual shrubs, trees or plants, but it may not be cost effective for entire plant beds. Be sure the mesh you buy is very tight - with less than 1/4 inch of space between the wires. You will need to bury the cloth securely in the ground at least six inches deep. Securing it deeply is the key to keeping voles from getting to the plant.
3. Look for Non-Chemical Repellents
If you go to plant and garden centers and look for non-toxic or organic sprays to repel rabbits or deer, you may see capsaicin listed as an ingredient. It is the substance that gives hot peppers their heat. You can create your own repellent by buying habanero sauce at a grocery store, or looking for dried hot peppers in a produce department. The hotter the pepper the better. You can grind them up yourself, but be sure you wear gloves when you touch them.

Rabbits

The most common type of rabbit you're likely to find on your property is a cottontail. Cottontail rabbits are easily recognizable because they have a tail that looks like a cotton puff. Other features include long ears, brown fur, and white fur covering their stomach.
Female cottontails have three or four litters of bunnies every year. They start giving birth in late winter, and the process continues into early fall. A female cottontail will build a softball sized nest and sit on it, keeping her bunnies warm and nursing them for two or three weeks.
Habitat
Cottontails thrive in a mixture of open areas and covered areas - especially rows of fences made up of brushy shrubs. They also like wooded areas and the banks of streams, especially if they have a protective woody border. During winter in much of the country, rabbits don't have the delectable foliage they nibble on during fall, spring and summer. They take to gnawing on bark from bushes or other woody-stemmed perennials.
When large numbers of rabbits turn up in residential areas - especially urban residential areas, they are there to enjoy the delicacies of your landscaping, but also because they are safe from the threat of predators - something they deal with in the wild or in sparsely occupied wooded areas.
Preventing the Damage
In some places, rabbits are considered protected game. That means that there are state or local wildlife regulations for relocating or releasing rabbits you trap to prevent them from causing further landscape damage.
*Check with state wildlife officials before trapping rabbits.
Physical Barriers
The best way to prevent rabbits from damaging or destroying your perennials is by surrounding shrubs or plant beds with fencing made of galvanized wire mesh (hardware cloth.) The space in the mesh should be no thicker than one inch. Rabbits can climb up to close to two feet above the snow's surface, so you need to have fencing that's at least two feet high.
You'll want to create the fencing by attaching hardware cloth to either metal or wooden posts. You'll need to pound both the wire mesh and the posts into the ground several inches and make sure that you secure it in the ground. This will keep rabbits from crawling under it.
If rabbits are gnawing the bark on your tree trunks, you can wrap the trunk with a cylinder of hardware cloth.

Deer

As suburban expansion encroaches on land that used to be rural, residential property has moved into the area where deer used to live in the wild. The damage they do to landscape and residential property varies according to the time of year, the number of deer competing for food from the same sources, and the amount of food that's readily available. Naturally, their preferred foods aren't available during winter, especially in places where snow covers vegetation and perennials are dormant.
According to the Department of Natural Resources at Cornell University, the most common type of deer found throughout North America is the White-Tail Deer. There are currently over 15 million deer dispersed throughout the United States. Herd sizes have increased dramatically in every state east of the Rocky Mountains. There are more than 500 types of plants that deer are known to eat, so if you've got deer in your area, it's safe to assume that your perennials are at risk for serious damage.
Because deer adjust to their surroundings so easily, they aren't afraid of people, and they brazenly trample on residential landscaping and eat whatever appeals to them.
What and How Much Deer Eat
The amount of food deer eat is dictated by the season, the sex of the animal, and how much they weigh. A buck weighing between 125 and 250 pounds needs to eat 4,000 to 6,000 calories a day. To get that many calories, that male deer would have to eat four to ten pounds of plants, twigs and other things. A lactating doe needs to eat at least 4500 calories. Deer need to forage for and eat the daily equivalent of three percent of their body weight - just to survive.
Repelling and Deterring Deer
Repellents are designed to either make the plant taste bad, or make it, or the surrounding area, smell unappealing. Commercially available products are typically sprays that must be applied on a regular monthly basis.
Some repellents are soap-based, but there is another type that is a hot sauce-like product that contains capsaicin, the heat-producing ingredient in hot peppers.
The most effective and arguably, the only full proof way to prevent deer from wreaking havoc on your expensive perennials is by constructing a fence around the entire perimeter of the area. To prevent deer from entering the area altogether, you need a woven-wire fence that is at least 8 feet tall. Shorter fences don't prevent deer from entering, and at best, they may be a deterrent.
For small areas, or for vegetable gardens, a welded wire enclosure - with fencing around the sides and an attached wire lid, will keep deer out altogether.