In late summer and fall, skunks and raccoons can cause damage to lawns as they search for earthworms, soil-dwelling insects, and insect larvae, such as white grubs. They dig up the lawn leaving behind large patches of loose turf, eat the grubs, worms, or other insects and leave behind a torn-up mess. The damage can be extensive and often happens overnight as both skunks and raccoons are active and feed at night.
Skunks create holes by pushing their noses into the lawn and then using their front paws to dig out the area. There can be so many holes rutted out that they coalesce together into a large disturbed patch of grass.
Raccoons use their front paws more like hands and will lift and flip sod pieces over. Sometimes the sod appears as if someone has neatly rolled it back with the intent of transplanting it elsewhere.
Management of this damage can be very difficult as extensive digging can happen in a short period of time (often overnight) and both of these animals have few reliable control measures.
Any control of this damage must first begin with an assessment of the number of white grubs in the soil. White grubs tend to be localized in the lawn and it is typical to have grub populations occur in irregular and isolated spots. Healthy turf can tolerate relatively high grub populations (as many as 20 or more grubs per square foot) before showing signs of injury. While damage to turfgrass caused by the grubs feeding requires a relatively high population density, grub populations only typically have to be at five or more grubs per square foot to attract skunks and raccoons for feeding. Determine the size of the grub population by inspecting nearby undamaged areas or those areas that have shown grub damage in the past. If numbers are low, no treatment is necessary.
If grub population numbers are high you can apply an insecticide to kill grubs currently in the soil. These curative insecticide applications are most effective in August and early September. In some years damage symptoms may not appear until after it is too late for effective treatment (late September through late October). Insecticide treatments after early October are not effective and are not recommended. The most effective treatment for grubs is with preventative insecticides applied from late May to early August. If damage is common each year or areas of your lawn frequently show grub damage, preventative treatments may be beneficial.
More detailed information about white grubs and their management can be found in this article: White Grub Control in Turfgrass
Often the most effective management option for skunk and raccoon damage to lawns is through exclusion. Fences can help with skunks as they do not jump or climb. A sturdy chicken wire or woven wire fence pinned to the ground can help keep skunks out of areas prone to feeding. Raccoons, however, can easily get over fencing materials. Exclusion options for raccoons need to cover the ground. Lay hardware cloth, chicken wire, or bird netting across the lawn areas receiving damage (or that have high grub populations) and secure it to the ground with landscape staples or bricks. Though a determined raccoon can lift wire fencing or claw through bird netting, it can make digging just frustrating enough to deter feeding and send the raccoon somewhere else for its meal.
Repellents that rely on strong scents to discourage wildlife pests from coming into an area may be helpful to prevent further damage to lawns by skunks and raccoons. However, repellents are typically not very effective at preventing additional damage to lawns.
These repellents can be used in two different ways. Some products, such as those containing castor oil, can be applied to the affected lawn surface to mask the scent of grubs, worms, and other insects making them hard to find. Other products, such as coyote urine, can be applied to the perimeter of an area and used to deter the animals from entering the lawn.
Scent repellents must be reapplied often, especially after rain events. The label directions will help determine the frequency of applications that are necessary. Treat those areas that have been affected as well as areas nearby to prevent further damage. While repellents may not be very effective, they can be used in conjunction with other management options to further help prevent damage.
Fixing the Damage
While it can be difficult to prevent damage to lawns caused by skunks and raccoons feeding, it typically happens in the fall which is the perfect time to repair the turfgrass.
Start by replacing any flipped or pulled-up pieces of sod. If conditions are dry, irrigate to help the loose pieces become re-established. Depending on the level of damage you can then decide to overseed to fill in the gaps or pull up entire sections and start over by reseeding or sodding. More information about overseeding, seeding, or sodding a lawn can be found in the resources below:
More information about skunks and raccoons and their management can be found in the following articles: