November 4, 2013

Take steps to avoid unwanted visitors

By JOLENE WALLACE, Cornell Cooperative Extension

---- — This time of year, we all start thinking about how to best protect our landscape plants and trees from harsh winter temperatures. 

During the spring and summer, we use mulch to keep weeds down and to keep the soil from drying too quickly. In winter, it’s a whole different story. Winter mulch is used to help maintain the temperature of the soil.

Note that I said maintain the temperature, not keep it from freezing.

The danger to perennials and landscape plants is from the alternate freezing and thawing of soil, which can result in heaving. Heaving is when the plant is pushed up and possibly even out of the soil because of temperature fluctuations. Small feeder roots can be broken during heaving, leaving the plant unable to absorb all the moisture it needs. Mulching around landscape plants after the plants have gone dormant and the soil is freezing helps to hold the soil temperature constant.

A common mistake is piling too much mulch around your plants, especially trees, creating a mulch “volcano.”

Woody shrubs and trees should not have mulch touching their trunks. During most seasons, this mulch keeps the trunk constantly moist, which can make it susceptible to disease. During the winter, this thick layer of mulch creates the perfect place for mice and voles to nibble on the outer layer of bark without being seen by predators. Since the nutrient and water needs of trees are met via the area of the tree just under the bark, this kind of girdling damage can easily kill a tree.

This is also the time when we need to take precautions against unwanted guests coming into our homes. I don’t mean that “favorite” family member that you have an obligation to entertain; I mean the mice that will be looking for a warm, cozy place to spend the winter.

Mice are able to get inside through a remarkably small opening. Any place that a pipe or vent enters your home can be a welcome mat for a mouse. Take the time to inspect your home, looking for openings that can be sealed up. Garage doors should be weather-stripped as well as doors going into your home. There’s a saying that if you see a mouse inside, there are others that you haven’t yet seen. Watch for the signs. Food on countertops with nibbles taken and “gifts” left nearby are a good indication that you have a visitor. 

Even if you never leave food out, bags of pet food and bird seed make easy targets, so put them in sealed, gnaw-proof containers.

If you do see signs that there’s a mouse in the house, don’t delay! Get mouse traps, bait them with peanut butter (cheese dries out quickly), and check them often. Traps are a better solution than poisons. If a poisoned mouse dies in an inaccessible place, you will have an odor problem.

Take measures now to keep the wildlife away from your trees and out of your homes so that when you are reading: “Not a creature was stirring, not even a mouse,” it will be the truth.

Jolene Wallace is the horticulture program educator for Cornell Cooperative Extension in Clinton County. Contact her at 561-7450 or