The appearance of raised ridges and scattered mounds across a lawn often causes homeowners to overestimate the scale of the mole problem. While this visible disturbance is a clear sign of activity, the number of animals responsible for the widespread tunneling is typically small. Understanding the actual population density and the nature of the tunneling is the first step toward effective management.
Distinguishing Mole Damage from Other Pests
Correctly identifying the source of the damage is necessary because different pests require distinct management techniques. Moles (Talpidae) are insectivores, primarily feeding on earthworms, grubs, and other soil-dwelling invertebrates, not plant roots. Their tunneling creates two primary signs: volcano-shaped mounds and raised surface ridges.
Mole mounds are conical, created when the animal pushes excess soil vertically to the surface. These mounds rarely have an open hole visible at the center. This differs from gopher (Geomyidae) mounds, which are fan or crescent-shaped and typically feature a plugged hole off to the side. Moles also create prominent, raised ridges or runways across the lawn, which are shallow tunnels. Voles (Cricetidae), which are rodents that consume plants, leave small, open holes and visible surface trails through the grass instead of ridges.
Understanding Mole Tunnel Systems and Population Density
Moles are solitary creatures that maintain large, complex tunnel systems, meaning extensive yard damage does not indicate a high population. A single mole can be responsible for an enormous network of tunnels extending hundreds of feet. These efficient diggers can create up to 150 feet of new tunnels daily while foraging for food.
The tunnel system has two main types: temporary surface feeding runs and deeper, permanent main runways. Surface runs are the visible, raised ridges used for hunting. Deeper runways are used for travel, nesting, and food storage. Because moles constantly patrol these tunnels for prey, their widespread work makes a small population appear massive. Population density is low, typically ranging from one to three moles per acre, though this number may reach up to ten per acre in areas with abundant food and moist soil.
Initial Steps for Effective Mole Management
The first step in management is identifying which tunnels are actively being used. Moles prioritize main runways over exploratory feeding tunnels. An active runway is one used multiple times daily for travel or hunting. To confirm activity, gently flatten a small section of a raised tunnel. If the tunnel is pushed back up within 12 to 48 hours, it is an active route suitable for control efforts.
Trapping is the most reliable and effective method for removal, especially when traps are placed in these main, active runways. Reducing the food source is another strategy, though it requires caution. While moles consume white grubs, their diet primarily consists of earthworms. Eliminating grubs may not force the mole to leave and could cause it to dig more aggressively in search of its preferred prey.