Discovering a lawn torn up by wildlife overnight is frustrating. Animals follow instinctual motivations like foraging for food or seeking shelter, which results in unsightly holes and overturned turf. Understanding the specific cause of the damage is the first step toward effective deterrence. This guide offers practical strategies to restore and protect your lawn.
Identifying the Animal and Motivation
The appearance of the damage provides clues for identifying the culprit and its motivation.
Shallow, cone-shaped holes or small, tilled-looking patches of grass often indicate a search for subterranean food sources, typically grubs or earthworms. Raccoons and skunks are the most common nocturnal offenders. Raccoons often peel back sections of sod, while skunks create numerous small, precise excavations.
Raised ridges or volcano-shaped mounds of soil, without a visible entrance hole, signal moles tunneling beneath the surface. Moles are primarily searching for earthworms, not grubs, as their diet is largely carnivorous. Small, shallow holes scattered randomly across the yard usually point to squirrels burying or retrieving nuts and seeds. Since these animals are motivated by food, removing the attractant is the most effective solution.
Burrows near foundations, under bushes, or along rock walls are frequently dug by animals seeking shelter, such as groundhogs or voles. Groundhogs create large entrance holes, sometimes up to a foot in diameter, often accompanied by a large mound of excavated dirt. Voles, which are mouse-like rodents, create numerous small, coin-sized holes connected by visible “runways” or trails in the grass. Identifying the motivation as either food foraging or shelter-seeking determines whether the next step should focus on food elimination or physical exclusion.
Eliminating Subsurface Food Sources
Removing the primary food source discourages digging by grub-foraging animals like skunks and raccoons. White grubs, the larvae of various beetles, are a major attractant. Removing them eliminates the incentive for animals to damage the turf. A healthy lawn can tolerate a population of up to five grubs per square foot without showing signs of damage, but a higher density will attract predators.
Effective grub control relies heavily on proper timing, targeting the insects when they are most vulnerable. Preventative chemical treatments, often containing active ingredients like imidacloprid or chlorantraniliprole, should be applied between April and mid-July before the beetle eggs hatch. These products work by remaining in the soil to kill the newly hatched, young grubs later in the season.
Curative treatments, used when an infestation is already visible, are best applied from mid-summer through September when the grubs are actively feeding and close to the surface. Biological controls, such as beneficial nematodes, offer an alternative non-chemical approach to grub management. Specifically, Heterorhabditis bacteriophora nematodes should be applied in late summer or early fall when soil temperatures are warm and grub feeding is at its peak.
Implementing Physical Exclusion Methods
Physical barriers prevent damage in specific areas and against animals motivated by shelter or superficial foraging. For animals that roll back sod, such as raccoons, or for newly seeded areas, temporarily laying down chicken wire or hardware cloth can block access. The wire must be secured tightly to the ground using sod staples or landscape pins so the animal cannot lift the edges.
For burrowing animals like groundhogs and voles, permanent underground barriers are necessary to deny shelter access. An L-shaped wire mesh fence is constructed by digging a trench at least two feet deep around the protected area. The mesh is inserted into the trench, and the bottom six inches are bent outward at a 90-degree angle, facing away from the protected space.
This outward-facing flange prevents animals from digging straight down next to the fence to gain entry. The mesh should extend at least 12 inches above the ground, and the trench is then refilled with soil, creating an impenetrable barrier. This method is particularly useful for protecting garden beds, decks, and the perimeter of sheds or foundations from persistent burrowers.
Using Sensory Repellents and Deterrents
Sensory deterrents rely on taste, smell, or startling the animal to make the area undesirable. Repellents based on strong scents, such as capsaicin from chili peppers, predator urine, or castor oil, can be sprayed or sprinkled on affected areas. Castor oil is particularly effective against moles, as it contaminates their food source and irritates their digestive system, making the soil environment unappealing.
These scent and taste-based repellents require frequent reapplication, especially after rain or irrigation, to maintain their efficacy. Motion-activated devices provide deterrence by startling the animal. Motion-activated sprinklers deliver a sudden burst of water, while ultrasonic devices emit high-frequency sounds or lights that discourage nocturnal visitors.
A strategy for long-term success is to rotate the types of repellents used, preventing the animals from becoming accustomed to a single deterrent. An animal that quickly habituates to a static visual deterrent may be frightened by a sudden noise or spray of water. Combining a taste repellent with a motion-activated device creates a multi-sensory environment that effectively trains the animal to avoid the treated area.