Raised ridges and scattered mounds of soil across a pristine lawn are a common frustration for Michigan homeowners and gardeners. These subsurface disturbances are the work of moles, insectivorous mammals often mistaken for rodents. Moles are tireless diggers, constantly creating new tunnels in their search for food. While their presence indicates a healthy soil ecosystem, their tunneling can severely damage turf roots and landscaping. This article provides practical, Michigan-specific guidance for managing these persistent pests.
Identifying the Mole Species and Damage Patterns
Michigan is home to two primary mole species: the Eastern Mole and the Star-nosed Mole. The Eastern Mole is the primary culprit for the most noticeable damage, creating the shallow, raised ridges that snake across lawns as surface feeding tunnels. These moles prefer drier, well-drained soil, which makes maintained lawns and gardens appealing targets.
The Star-nosed Mole, recognizable by its unique ring of 22 fleshy nasal appendages, typically prefers moist or swampy habitats. This species is responsible for the volcano-shaped piles of excavated soil, known as molehills, as it digs deeper, more permanent tunnels. It is important to distinguish mole damage from that of voles, which are rodents that create small, above-ground runways and chew on plant roots, as moles do not eat vegetation.
Legal and Safety Considerations for Removal
Michigan law classifies moles as unprotected species, meaning property owners can control them year-round without needing a specific permit from the Michigan Department of Natural Resources (DNR). This allowance grants residents flexibility in addressing mole problems on their private property. However, it is essential to follow strict safety guidelines when implementing any control method, particularly when using lethal techniques or restricted chemicals.
Using poisonous baits, such as those containing zinc phosphide, requires extreme caution near children and pets to prevent accidental ingestion. Furthermore, certain methods like flooding or the use of gas cartridges are often restricted or illegal in urban areas due to the risk of impacting groundwater or neighboring properties. Always prioritize the safety of people and non-target animals, and consult local ordinances before deploying any chemical control method.
Lethal Control Methods: Effective Trapping Techniques
Trapping is widely considered the most reliable and efficient way to eliminate an existing mole infestation and is the preferred method for long-term control. Success hinges on correctly identifying and setting traps in active tunnels, which are runs the mole uses regularly for travel. To check for activity, simply flatten a section of the surface tunnel with your foot; if the ridge is pushed back up within 12 to 24 hours, the tunnel is active and suitable for trapping.
Three main types of lethal traps are commonly used: the scissor trap, the harpoon trap, and the choker loop trap. The harpoon trap is often the easiest to set and works best in shallow, surface runs, driving tines downward into the tunnel when triggered. Scissor traps and choker loop traps are generally placed in deeper, more established tunnels. These traps are set by cutting a plug of soil out of the run, allowing the mole to trigger the mechanism while attempting to reopen the blocked passageway. Place the trap securely over the run, ensuring the trigger pan is positioned precisely within the collapsed section, and check the trap frequently.
Non-Lethal and Repellent Strategies
For homeowners seeking alternatives to lethal removal, non-lethal and repellent strategies offer a way to deter moles from the area. The most common chemical repellents utilize castor oil, which is thought to irritate the moles’ digestive system or make their underground food source unpalatable. These products are typically applied as a granular or liquid spray and require reapplication, especially after heavy rain, to maintain their effectiveness.
Physical barriers can also be implemented, such as burying hardware cloth or a wire mesh vertically around garden beds or high-value areas to block mole access. However, many other popular deterrents, including ultrasonic devices, vibrating stakes, and various home remedies, have been shown to be inconsistent or largely ineffective. Moles are primarily guided by their sense of smell and touch, and they often ignore these sonic or vibration-based devices.
Long-Term Prevention Through Habitat Modification
The most sustainable strategy for preventing future mole infestations involves reducing the availability of their primary food sources. Moles are insectivores whose diet consists mainly of earthworms, but they also feed on insects, beetle larvae, and grubs. Reducing the population of these invertebrates makes the yard a less desirable habitat, encouraging moles to move elsewhere.
One method is to manage soil moisture, as moles are attracted to moist, loamy soil where their prey thrives. Reducing excessive lawn watering can make the ground less appealing for foraging. While controlling grubs is often suggested, earthworms make up the largest portion of a mole’s diet. Modern grub-control insecticides do not significantly impact earthworm populations, so controlling a severe grub problem should not be relied upon as the sole method for mole prevention.