Moles

Species names: 

Shrew-mole, Neurotrichus gibbsii 

Broad-footed mole, Scapanus latimanus 

Coast mole, Scapanus orarius 

Townsend’s mole, Scapanus townsendii 

Size: 

Moles are around 4-7 inches and weigh about 2-5 ounces 

Signs of their presence: 

Tunnels, or “runs,” in the soil or lawn. (Runs of star-nosed moles are usually deeper and less noticeable than those of hairy-tailed moles, except, at times, in well-watered golf courses.) These tunnels are seen most often in the spring and fall, when the soil is moist, soft, and easy to dig. Moles make two kinds: feeder and travel tunnels. Feeder runs look like a long, squiggly, rounded ridge that’s about two inches wide. Feeder tunnels tend to be short and very crooked, because if a mole finds an area that’s full of food, it tends to dig all around, feeding. They’ll abandon these runs when there’s not much food left in them. Dead grass over the run is usually a sign of an old, abandoned run. (Moles don’t eat grass, but they may loosen the roots from the soil, which can kill it). Their travel tunnels are usually long and straight and often follow an edge, such as a driveway, fence, or foundation. Look for travel tunnels that continue into wooded areas because these will be the best spots in which to set traps. 

Molehills (also called boils or mounds): small, cone-shaped piles of soil that are usually just a few inches high and anywhere from a few inches to a foot wide. They vary in size. Often seen in the late fall, as the moles prepare for winter by digging deeper tunnels that are under the frost line. At that depth, the moles can’t toss up the soil as they go, which is what they do when they’re near the surface. So they’ll usually dig forward for a while, then stop, and carry the soil up to the surface where they dump it, creating the molehill. Moles also dig deep tunnels in the summer when the soil is dry. Then, they’re following the earthworms, one of their favorite foods. 

It’s unlikely you’ll see or hear moles, or find scat or tracks because they spend their time underground. Although they feed and travel in the shallow, surface tunnels described above, they find shelter and raise their young in deeper tunnels that could be 6-24″ below ground. 

Moles are often accused of crop damage that was actually caused by voles. Although moles rarely eat roots, their tunnels may damage them. So how do you tell a mole from a vole? 
 

MOLES have: Voles have: 
very small eyes small eyes 
no external ears small, but definitely noticeable ears 
a naked, pointy snout furry noses 
large front feet that are turned sideways, and big claws. (Excellent shovels). small, mouse-like feet 

Diet: 

Mostly insects. Grubs, beetle larvae, earthworms, and some carrion. Occasionally, frogs and mice. Star-nosed moles may catch minnows. They must eat 70–100 percent of their body weight each day to have enough energy to burrow. Occasionally, they’ll eat seeds, roots, or bulbs. 

Typical activity patterns: 

Social style: Eastern moles are mainly solitary creatures, with the exception of breeding season. 

Daily activity: Moles are most likely active throughout the day and night. They need to eat a lot to keep up their energy levels. 

Hibernator? No. They simply move deeper into the soil, tunneling below the frost line. 

Migrates? No. 

Where found: 

In Oregon moles can be found throughout the state, excluding the more arid regions of the state. 

Habitat: Lawns, meadows, orchards, and woods with moist, loose soil. Hairy-tailed moles prefer loamy, sandy soils well covered with plants and avoid wet, dry, or heavy clay soils. Star-nosed moles prefer swamps, bogs, and low, wet meadows (they’ve even been seen swimming under ice in the winter) but can manage in somewhat drier locales.  

Territory and home range: Territorial. Two moles usually fight when they meet, except during the mating season. The home ranges of male and female moles overlap, but the home ranges of the females do not seem to overlap with those of other females. Some tunnels overlap territories and are used like highways by two or more moles. The males range over about 2 acres, females over a half-acre. 

Breeding habits: 

Pair bonding style: Polygamous. Female raises the young alone in an underground nest chamber lined with leaves and grasses. The nest chamber is usually found in a deeper tunnel, perhaps as far as two feet underground. 

Breeding dates: Late February to March. Gestation takes about 42 days. 

Birthing period: April to May. 

Litter size: 3–7. 

Weaning dates: Between 4–5 weeks of age. 

Common nuisance situations: 

Time of year: Spring (April–May) and fall (September–November), when surface soil is moist and easy to dig, and grubs and worms are nearest the surface. You may receive a few calls as soon as the snow melts, which reveals old damage, but should wait to see if there are still moles present. 

What are they doing? 

While helping rid lawns, gardens, and golf courses of grubs, moles create unsightly runs. Their tunnels disfigure lawns and can wreak havoc in a garden. 

Disease risks: almost none. 

Legal status in Oregon: 

Unprotected. 

Best practices 

 Moles can have a positive effect by eating a huge number of grubs that damage lawns and gardens. As well as, eating insects that can be bothersome while you try and relax on a summer night. Their tunnels also help aerate the soil. However, they can cause some damage with their tunnels. Trapping is currently considered most effective, but repellents, exclusion, and habitat modification techniques may also contribute to an effective strategy and be preferred by some of your customers. 

Fence off gardens and flowerbeds: 

Areas can be fenced off with chicken wire, hardware cloth or sheet metal. The fence should be two feet high and buried a foot deep. Bend the bottom of the fence 90° degrees out from the area being protected, the section that is bent should be a foot long. This helps prevent the moles from burrowing under the fence. 

Trap the Moles. Trapping has proven to be one of the most effective ways to stop moles from causing damage.  

Find the tunnels that are active  

This can be done by stepping on a portion of a tunnel, if the dirt is pushed back up in 24 to 48 hours then it is an active tunnel. 

There are a variety of traps that can be used, some are easier to set up than others. 

Some of these traps are out of sight, however some stick out of the ground and can be dangerous to children and pets. 

Consult the landowner first on whether there may be an issue with one sticking out of the ground. 

Trapping strategies: 

Lethal traps: 

There are several effective lethal traps for moles, including harpoon-shaped, plugger, or scissor-jawed traps. A newer model, the NoMOL® trap, doesn’t contain a spear or heavy springs so you may find it easier to use. 

Trap in the spring or fall, when the soil is moist and the moles are closer to the surface. 

Finding an active tunnel 

Find a ridge in your lawn and step on it, thus closing the tunnel 

If the ridge reappears in 24 to 48 hours then it is an active tunnel 

If not, then try a new area 

Choose an area where the tunnel runs in a straight line 

Dig into the ridged area and find the mole tunnel 

Pat soil down firmly where the trap will be set 

Set trap with trigger pressed against the compressed dirt that way when the mole goes to reopen the tunnel, the trap will be triggered 

For the best results set multiple traps within the area of interest 

Watering a dry lawn will entice worms and moles closer to the surface, where the moles will be easier to catch. 

Set locations 

Best: an active travel tunnel that extends into a wooded area.  

Good: any active travel tunnel, or a molehill.  

Questionable: feeding tunnels. The moles may not return to them. 

Place two traps in each tunnel, one in each direction. 

Homeowners can help you by checking lawns daily for new damage. 

Check traps frequently. If the mole is still alive, remove the stake carefully and grasp the wire to pull out the trap. Use a spare NoMol® trap to kill the mole. Slide the trap’s arms so that the jaws are just behind the mole’s front feet, then release the tongs. 

Preferred killing methods: 

A lethal trap. 

Acceptable killing methods: 

Pesticides (gel bait and grain-based baits), for those with a commercial pesticide applicator licenses. 

Control strategies: 

Disturbing their tunnels can cause them discomfort and drive them out 

Stomp on tunnels to collapse them every time them appear  

Castor Oil Repellents deliver a foul smell to the moles 

There are liquid based sprays and granules that can be used 

Granules can be spread over the yard and are activated by water 

Liquid based sprays work with your hose water to cover the area sprayed 

Homemade repellent can be made by combining 6 ounces of castor oil with 2 gallons of water and 2 tablespoons of detergent. Apply one sixth of the mixture to every 1000 square feet of soil.  

Applying it before it rains or watering the applied area helps with absorption.  

Ultrasonic Repellents affect the moles hearing 

Since moles are almost blind, they rely on their hearing and touch 

Ultrasonic repellents send vibrations and ultrasounds into the ground which irritate the moles 

Grub treatments (insecticides) may get rid of the grubs in your lawn but may leave worms that the moles can eat. Insecticides may not work well in heavy, clay soils as the insecticides can get trapped in the soil layers 

One may try to get rid of the grubs with insecticides but that will still leave worms present for the moles to eat. Since worms are so beneficial to a lawn one should never try to get rid of all of them. 

Attempting to control the moles food source is difficult since they have a varied diet. 

Grain-based baits (containing zinc phosphide) don’t work that well because moles don’t normally eat grain. If they aren’t attracted to the bait, they’re not likely to ingest the poison. 

Borders of marigolds are thought to repel moles but haven’t been tested. 

Make the area less attractive for moles: 

Moles prefer wet, low areas that are rich in worms and grubs. Moles follow their food sources, if there are fewer grubs and worms, the moles may move on. However, grubs and worms are not the only food source for moles.  

Control Strategies that don’t work particularly well, or aren’t legal in Oregon:  

Flooding their holes with water may stop them from using them for a little while, but they will be back once the holes are suitable. 

Flooding their tunnels may also flush them out of the tunnels if they have not yet really established themselves. This can lead to a real-life game of Whack-a-Mole, so bring a shovel 

Some use ferrets to control the population, however buying a ferret to just control mole populations may not be a smart investment.  

Getting rid of their food source may only provide short term relief and if the moles are persistent, it can become an expensive control measure.  

For information on legal pesticides click the following link, https://www.oregon.gov/ODA/programs/Pesticides/RegulatoryIssues/Pages/RegulatoryIssuesCompliance.aspx 

Interesting Facts and Myths: 

Moles are often mistaken for voles, mice, and shrews. If in doubt, check your field guides. 

Many people believe that there’s a mole in every tunnel they see. The good news is that even though you may see dozens of tunnels, there are probably only a few moles in the yard. Possibly only one or two.  

 Moles dig fast: about 18 ft./hour. They may be able to tunnel 100 feet a day or more, depending on soil conditions. You may think your lawn is full of moles, when it’s just the home of a few, very busy little guys.