Moles are subterranean mammals that can quickly turn a manicured lawn into a series of raised ridges and volcano-shaped soil mounds. These insectivores create extensive tunnel systems just beneath the surface as they hunt for earthworms, grubs, and other soil-dwelling invertebrates. While they rarely consume plant roots, their tunneling activity disrupts the root systems of grass and garden plants, leading to cosmetic damage and plant death. When the damage becomes intolerable, lethal elimination methods are often the most effective solution.
Lethal Trapping Methods
Trapping is widely considered one of the most reliable ways to remove moles, provided the traps are correctly placed. Success relies on identifying the main travel runs—the longer, straighter tunnels used repeatedly—rather than temporary foraging tunnels. To find active pathways, flatten a section of a tunnel and check 12 to 24 hours later to see if the mole has pushed the soil up again.
Several mechanical devices are available. Scissor traps feature two metal loops that snap shut when a mole disturbs a trigger plate placed in the run, often providing a visual indicator above ground when sprung. Harpoon traps, sometimes called spear traps, use sharp tines driven down into the tunnel when the mole moves beneath the trigger plate.
A third category is the choker loop or tunnel trap, which is set directly inside the mole’s runway. These traps use a crushing wire loop or spring-loaded jaws that close as the mole passes through. Proper setting technique is necessary to ensure the device is securely anchored and the trigger mechanism is aligned with the mole’s path. Trapping is a targeted method that offers proof of removal without introducing chemical agents.
Poison Baits and Chemical Killers
Chemical elimination methods use toxic baits designed to resemble the mole’s natural food source, such as earthworms or grubs. The most common active ingredients are bromethalin and zinc phosphide. Bromethalin is a potent nerve toxicant that causes swelling in the central nervous system, leading to paralysis and death within one to two days of ingestion. Since there is no antidote, bromethalin poses a significant hazard to pets, especially cats and dogs, if they consume the bait.
Zinc phosphide reacts with stomach acids to release phosphine gas, resulting in a quick kill, often within a few hours. However, the stomach contents of a mole killed with zinc phosphide can remain toxic, creating a risk of secondary poisoning if the carcass is consumed by a scavenging animal. Other methods involve using smoke or gas products placed directly into the tunnel system to asphyxiate the mole or fill the tunnel with a lethal gas.
Safety and Legal Considerations
The use of any lethal mole control method requires careful attention to safety and adherence to local regulations. Product labels must be followed precisely regarding application rates, placement, and required safety gear. For chemical baits, this includes wearing protective gloves during handling and ensuring the bait is placed deep within the tunnel system to prevent access by children or non-target animals.
Toxic baits must often be used with tamper-resistant bait stations when placed in areas accessible to pets or wildlife. Moles are often classified as wildlife, meaning control methods are subject to state and local protection laws. Certain highly toxic chemicals may be designated as Restricted Use Pesticides (RUPs), meaning their purchase and application are limited to certified applicators. Regulations regarding permissible traps or chemicals vary widely by jurisdiction.
Choosing the Right Method
The best choice for mole elimination depends on the risk to non-target species, the required effort, and the speed of results. Lethal trapping is generally the most targeted and effective method, especially in high-traffic areas with pets or children, due to the minimal risk of secondary poisoning. Although trapping requires more initial effort to identify and set the devices correctly, the equipment is a one-time purchase, making it cost-effective over time.
Chemical baits offer a lower labor solution, requiring only the placement of the product into active tunnels. However, using toxic agents like bromethalin or zinc phosphide introduces a risk of accidental poisoning to pets and scavenging wildlife. For a single, localized issue, a well-placed trap is often the fastest and safest solution. Chemical baits may be considered for widespread infestations requiring less manual oversight, provided the user is aware of the inherent risks.