Leatherjackets are a part of natural ecosystems, but large populations of these soil-dwelling pests can undermine your lawn’s health and appearance. With early identification and targeted lawn care strategies from Lawn Doctor, you can protect and reinforce your lawn against pests and keep it healthy and lush.

What Are Leatherjackets?

Leatherjackets are the larval stage of crane flies, also known as daddy long legs. While adult crane flies don’t feed, larvae feed on grass roots and can become a concern when their populations become disproportionate. They’re common from fall through spring, particularly in regions with mild and wet climates.

The leatherjacket life cycle begins in late summer, when adult crane flies lay eggs in the soil. The larvae hatch within 2 weeks and typically feed continuously until they pupate in the late spring or early summer. After pupating, adult crane flies only live a few days, long enough to lay up to 300 hundred eggs each and restart the cycle.

How to Identify Leatherjackets

Leatherjackets are grayish-brown and worm-like in appearance, and their name comes from their distinctively thick and slightly leathery skin. They may grow up to an inch long, but they don’t have a distinct head and legs.

Leatherjackets tend to hide beneath thatch layers or just under the soil’s surface during the day. They are more active at night or after rainfall or watering, during which they move closer to the surface to feed. You may be able to peel back small sections of turf to inspect for leatherjackets during or at the end of their active periods.

Signs of a Leatherjacket Infestation

Leatherjackets are part of normal ecosystems and aren’t innately harmful when present in balanced numbers. Large populations, however, can cause damage and may come with other signs.

Thinning or Yellow Lawn Patches

As larvae feed on roots, grass is less able to absorb nutrients and water. This mimics the effect of drought stress and nutrient deficiency and causes discolored or patchy areas of grass that may expand as leatherjacket feeding continues.

Turf Lifts Easily

Since leatherjackets consume and weaken the roots anchoring the turf into the soil, infested areas may sometimes peel back in large sheets with minimal resistance.

Increased Animal Populations

Many animals feed on leatherjackets, and you can expect birds, raccoons and other small creatures to visit your lawn occasionally. A sudden increase in animal activity, sometimes evident by small holes or unearthed soil from pecking birds or digging animals, may indicate a larger presence of leatherjackets.

Grubs Appear On Hard Surfaces

Leatherjackets sometimes emerge during damp conditions. If you find larvae on paving stones, sidewalks or patios after rain or irrigation, the nearby soil may have a leatherjacket infestation.

What Attracts Leatherjackets?

Several environmental factors may contribute to conditions that encourage crane fly and leatherjacket populations.

Excessive Water or Poor Drainage

Moisture is a primary attractant. Crane flies prefer damp soil for egg-laying, and lawns with poor drainage or excessive watering become ideal nurseries for larvae.

Newly Laid Turf

Newly laid turf, especially if frequently watered, is an ideal habitat for crane flies because it offers rich nutrients and soft soil.

Thick Thatch Layers

Thick thatch layers provide shelter to leatherjackets while maintaining soil moisture. This insulation and warmth protects larvae from cold temperatures and supports their survival.

Lack of Natural Predators

Healthy predator populations regulate leatherjacket numbers, but activities that impact habitats may keep these animals away. Without adequate biodiversity, pest populations may increase without checks from natural predators.

How to Get Rid of Leatherjackets

Normal populations of crane flies and leatherjackets are acceptable, but large populations and active infestations require targeted removal to protect your lawn.

Nematodes

Beneficial nematodes are microscopic organisms that prey on leatherjackets. They seek out larvae and infect them with natural bacteria, which eliminates them without harming plants, animals or people. This method is best applied in early fall or spring when larvae are most active, preferably by professionals who can navigate environmental conditions to maximize results.

Chemical Treatments

Insecticides with imidacloprid, chlorantraniliprole and other active ingredients target and reduce leatherjacket populations. These treatments absorb into plants and their roots without harming them, which larvae then feed on. Professional application is best for managing treatment timing.

How to Prevent Leatherjackets

A healthy and resilient lawn is the best defense against leatherjacket infestations. Follow these lawn care practices:

• Mow regularly to keep grass and roots healthy.
• Water deeply and aerate soil to promote root growth and drainage.
• Dethatch your lawn periodically to prevent buildup.
• Monitor for crane fly activity — high adult populations in late summer may indicate current or future infestations.
• Apply beneficial nematodes with professional assistance as a preventative measure.
• Repair damaged lawn areas with overseeding or resodding as needed.
• Encourage natural predator populations with bird feeders and predator-attractant plants.

With the right combination of upkeep and professional support, your lawn can stay healthy, green and free of leatherjacket damage. Lawn Doctor offers expert lawn pest control and personalized strategies to strengthen your lawn. Learn more about our professional pest control services.