Posts Tagged: voles
The Invasion of the Voles
You really do not want voles (also called meadow mice) moving into your garden. They are larger than a house mouse or deer mouse but do not quite reach the size of an adult gopher or rat. Although it is said that they can mature to 5–8 inches long including the tail, they are most commonly on the smaller side of the range. With their charming pudgy shape, beady black eyes, small ears, soft gray/brown fur, and rather short and oddly furry tail, their appearance could be thought of as somewhat cute or endearing. That is, until you experience how quickly they can lay waste to your beloved garden.
When they are not ravaging your garden plants, these rodents spend much of their time hiding in their burrows. They are most likely to be seen during the cooler parts of the day such as dawn and dusk, when they dash from one burrow to another, or scurry from dining on your favorite plant into the safety of their burrows. The burrows have openings that are 1 ½ to 2 inches wide. There are often obvious runways from the burrows where soil is trampled down by their repeated scampering back and forth. Voles will happily burrow into both mulch and soil, and where there are dense weeds or long grasses (a favored habitat), voles will create distinctive tunnels through the vegetation.
Vole populations regularly go through cycles of low to high numbers. Their numbers generally peak each 3 to 6 years or so, but don't count on being able to guess when the next vole invasion will occur. These cycles are not predictable. Their numbers can increase to staggering amounts during a population explosion, soaring to as many as several thousand per acre.
If you have voles in your garden, you already know they eat a very wide variety of plants. Unlike rats and mice that are out and about wreaking havoc at night, voles are active both day and night, and year-round. Also, unlike rats and mice who have favorite foods and tend to go after sweet, ripe fruits and the most succulent vegetables, voles are not terribly picky. They will eat a wide variety of plants including zucchini, cucumber, green bean, tomato, and artichoke. Basil, dill and parsley are some herb plants that may be there one day and gone the next. Flowers such as marigolds, cosmos, yarrow, and sunflower are also part of their menu plan.
Voles do take an occasional break from their feeding frenzy to breed and can have 5 to 10 litters of offspring each year. They can have 3–6 young at a time. One redeeming quality is their short lifespan of just a few months to a year, and the fact that after a season of super high numbers, the population tends to go back to normal.
There are several effective control methods such as habitat modification (make the area less hospitable to them), trapping (setting many, many mouse traps), and exclusion (creating impassable barriers around your garden, your garden beds, or even individual plants).
Vole management
Habitat modification is an effective way to reduce vole damage in the landscape. Remove weeds, heavy mulch, and dense vegetative cover to reduce their food sources and expose them to predators. Voles prefer not to feed in the open so 4-foot buffer strips of open ground can help protect trees or other plants.
Because of the large numbers of voles that can be present during a population explosion, exclusion is often the most important option. Wire hardware cloth with ¼ inch or smaller mesh makes a good barrier if it is at least 12 inches tall. Make sure it surrounds the plants completely and bury it into ground 6 to 10 inches deep. Metal roof flashing, sold in hardware stores, makes a very effective barrier. It comes in rolls with varying widths. Unlike gophers, who dig deep burrows, voles usually dig down only a few inches. They are not very athletic and don't climb or jump very well like rats can, so barriers don't have to be terribly tall to be effective.
Trapping can be effective if vole numbers are low or they are in a small area, but difficult when the population is high. The key is to use many mouse traps at the same time. For detailed directions on how to place traps, see the link below.
Voles are an important part of the natural food chain. They are prey for a variety of predators including hawks, crows, owls, snakes, raccoons, bobcats, foxes, coyotes, opossums, and domestic cats. They may not keep vole populations adequately controlled near homes because of their reluctance to hunt close to homes.
There are toxic baits available, but care must be taken to ensure the safety of children, pets, and nontarget animals such as the predators listed above. See the link below for more information.
This UC IPM (integrated pest management) link is an excellent source for information on identifying and managing voles:
https://ipm.ucanr.edu/home-and-landscape/voles/pest-notes/#gsc.tab=0
This link will help you determine whether damage to your yard is due to voles, gophers or moles:
https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=49119
Help Desk of the UC Master Gardeners of Contra Costa County (SMH)
Vole damage to root crown and lower bark of a tree. Credit: Jack Kelly Clark, UC IPM
Vole damage to turf showing burrows and runways. Credit: Terrell P. Salmon, UC IPM
Hardware cloth barrier. Credit: S. Hoyer
Because they cannot climb the metal sides, your plants can be safe from voles in beds like these. Credit: S. Hoyer
Another very effective option is to add an (at least 12-inch tall) metal flashing barrier to wooden raised beds. Credit: S. Hoyer
FAQ: Moles, Voles & Gophers
In this blog article we answer some frequently asked questions about moles, voles, and gophers...
Go For Control
by UC ANR Staff Writer
Publication helps growers identify the rodent species on their properties, their life cycles and tools available to control them
Burrowing rodents can cause extensive and expensive damage to orchards and crop fields. To manage the pests without chemicals used on conventional farms, organic growers can consult a new publication from UC Agriculture and Natural Resources scientists.
“Burrowing Rodents: Developing a Management Plan for Organic Agriculture in California” outlines management within organically acceptable methods using an integrated pest management approach.
California ground squirrels, pocket gophers and meadow voles are the three most common species that cause damage. Squirrels chew on seedlings, fruit and nuts, killing young trees and reducing crop yields. In addition to plants, ground squirrels, pocket gophers and voles can chew on irrigation lines, and their burrow systems can channel water away from plants and erode the soil. The holes and mounds created by burrowing rodents pose hazards to farmworkers and farm machinery.
This publication helps growers identify the rodent species on their properties, their life cycles and tools available to control them.
“Growers can read about how to effectively select and set a range of traps for burrowing rodents,” said co-author Margaret Lloyd, UC Cooperative Extension small farms advisor for the Capitol Corridor. “Traps are an important tool for organic management, but maximizing control comes from integrating knowledge. Here we present information about rodent biology, trap efficacy, biocontrol, habitat management, plant protection and other approaches to collectively manage the pest problem.”
In the publication, Lloyd and Roger Baldwin, UC Cooperative Extension wildlife specialist in the UC Davis Department of Wildlife, Fish and Conservation Biology, review the effectiveness of commercially available traps – where to place the traps, whether to use attractants, and methods of euthanizing the animals.
They also offer cultural techniques for deterring rodents such as flooding fields and deep ripping soil to destroy burrow systems. Crops for orchard floors or cover cropping can be selected and managed to minimize habitat that protects and encourages gophers and voles.
For biological control, they suggest barn owls, raptors and snakes might be able to assist, but warn growers that predators alone will not be able to eat enough of the rodents to reduce the high populations to tolerable levels for many growers.
“Effective management will rely on a suite of tools,” said Baldwin.
The 15-page publication is available for free download at https://anrcatalog.ucanr.edu/Details.aspx?itemNo=8688.
gopher
Voles in Your Yard?
Voles are small, mouselike rodents that can be pests in gardens and landscapes. They damage many...
Serious Garden Pests: Voles, Moles, and Gophers
It's an exasperating experience. You go to the nursery, pick out a flowering plant, shrub, or tree...
Comparison of mole and gopher mounds, UC, Davis