One of the most persistent questions homeowners and gardeners have about these subterranean neighbors is whether moles cover their holes. The short answer is generally no; moles do not typically bother to conceal the entrance to their tunnels. Understanding this behavior is crucial for effectively managing these industrious creatures and interpreting the complex landscape of mounds and ridges they create in your yard.
The Reality of Mole Hills and Surface Tunnels
When you spot a conical mound of soil in your lawn, you are looking to a mole's final exit. After the animal has finished foraging for grubs and worms, it pushes the excess soil to the surface to create a volcano-shaped mound. Unlike gopher mounds, which often have a distinct plug, a molehill is characterized by a central volcano with a visible hole at the peak. This is the primary reason people believe moles cover their holes, but the opposite is true; they are revealing their exit.
The Function of "Molehills"
The act of pushing soil to the surface serves a vital purpose for the mole. The tunnels just beneath the grass are shallow and unstable; the animal needs to vent the tunnel system and remove compacted soil to maintain airflow and ease of movement. If they tried to cover the hole immediately, they would simply pack down the very tunnel they are trying to navigate. Leaving the hole open is a practical necessity, functioning as a natural air vent and pressure release valve for their underground network.
Deciphering Mole Activity vs. Vole Activity
Confusion often arises between moles and voles, which can lead to misidentification of holes. Voles are herbivores that create shallow surface runways and feed on grass stems, leaving the turf looking chewed but not mounded. Moles, being carnivores, tunnel deeper in search of live food, creating the tell-tale volcano holes and raised ridges. Because voles utilize existing mole tunnels but do not create the same type of exit holes, property owners might mistake the absence of a plug for vole activity rather than understanding the distinct habits of the mole.
| Feature | Mole | Vole |
|---|---|---|
| Primary Diet | Insects, Grubs, Worms | Grasses, Seeds, Roots |
| Surface Evidence | Molehills (volcano-shaped) | Runways (grazed grass) |
| Hole Coverage | Left open as a vent | Often hidden in dense grass |
The Temporary Plug Myth
While it is rare, there are specific circumstances where a mole might temporarily cover a hole. If a mole detects a potential threat, such as the vibration of a footstep or the scent of a predator, it will quickly retreat to the safety of its deeper main tunnel. In doing so, it might kick a small amount of soil back over the entrance to the shallow feeding tunnel to hide its presence. However, this is a temporary security measure, not a permanent habit. Once the coast is clear, the soil settles, and the cycle of excavation continues, leaving the main entry points exposed.
Why They Don't Bother to Cover Up
From an evolutionary standpoint, covering every hole would be a massive waste of energy for a mole. Their entire lifestyle is built around constant excavation; they tunnel through the earth at a rate of up to 18 feet per hour. Spending time to pack down soil would slow down their efficient feeding cycle. Furthermore, these open holes act as additional exits for quick escapes. In the dark, soil-filled environment, maintaining multiple open vents is a survival strategy, allowing them to move rapidly between depths without getting trapped in a sealed tunnel.
Effective Management Strategies
Because moles do not cover their holes, the presence of these volcanoes is a clear indicator of active tunneling. Simply filling these holes with dirt is a futile exercise, as the mole will immediately reopen the vent or create a new one nearby. Effective control focuses on disrupting their food source or trapping the animal. Applying insecticides to reduce grubs can encourage the moles to move on, while the most reliable method for elimination is the strategic placement of traps in the main runways, which are found by flattening a section of tunnel and checking back in 48 hours to see if it has been reopened.
