Leatherjackets, the larvae of crane flies (Tipulidae family), are a significant pest for turfgrass growers in the UK. Their presence can cause substantial damage to lawns, golf courses, and sports fields, making it essential for those in the turfgrass industry to understand their lifecycle, impact, and control measures. This article provides an in-depth look at leatherjackets and offers practical advice for managing this pervasive pest.

What are Leatherjackets?

Leatherjackets are the larval stage of crane flies, commonly referred to as “daddy longlegs.” These larvae are grayish-brown, legless, and can grow up to 30 mm in length. They are named for their tough, leathery skin, which provides some protection against predators and environmental factors.

Lifecycle of Leatherjackets

Understanding the lifecycle of leatherjackets is crucial for effective management. The typical lifecycle includes the following stages:

  1. Egg Stage: Adult crane flies lay eggs in late summer to early autumn, usually in moist, well-vegetated soil. Each female can lay hundreds of eggs, which hatch within two weeks.
  2. Larval Stage: After hatching, the larvae (leatherjackets) feed on the roots and crowns of turfgrass. This stage lasts through the winter and early spring. They are most active at night and on cloudy days.
  3. Pupal Stage: In late spring to early summer, the larvae pupate in the soil. The pupal stage lasts for about two weeks.
  4. Adult Stage: Adults emerge from the pupae, mate, and the cycle begins anew.

Impact on Turfgrass

Leatherjackets primarily damage turfgrass by feeding on roots, which weakens the plants and makes them more susceptible to stress from drought, disease, and wear. Signs of leatherjacket infestation include:

  • Yellowing and Thinning Grass: Patches of grass may turn yellow and thin out, resembling symptoms of drought stress or nutrient deficiency.
  • Loose Turf: Heavily infested areas may feel spongy underfoot and can be easily lifted away from the soil.
  • Increased Bird Activity: Birds such as crows and starlings may be seen pecking at the turf to feed on the larvae, often causing further damage.

Why Are Leatherjackets Becoming More Common?

There are several reasons why leatherjackets appear to be a more common problem than in the past:

  1. Climate Change: Warmer temperatures and milder winters in the UK have created more favourable conditions for crane flies to thrive. These climatic changes can lead to higher survival rates of leatherjackets over winter, resulting in larger populations.
  2. Changes in Turfgrass Management Practices: Modern turfgrass management practices, such as reduced use of pesticides due to environmental regulations and increased focus on sustainable practices, have inadvertently provided a more hospitable environment for leatherjackets.
  3. Increased Urbanisation: Urban expansion and changes in land use can disrupt natural predator habitats, leading to an imbalance where leatherjackets can proliferate without natural checks.
  4. Resistance to Pesticides: Over time, leatherjackets may develop resistance to commonly used insecticides, making them harder to control with chemical means alone.

Integrated Pest Management (IPM) Strategies

Effective management of leatherjackets involves a combination of cultural, biological, and chemical methods, following an Integrated Pest Management (IPM) approach.

  1. Cultural Controls:
    • Regular Monitoring: Inspect turf regularly, especially in late summer and early autumn, for signs of crane fly activity and larvae.
    • Proper Irrigation: Maintain balanced moisture levels. Overly wet conditions can attract crane flies, while excessively dry conditions can stress turfgrass.
    • Aeration and Thatching: Regular aeration and thatch removal can reduce the habitat suitability for leatherjackets.
  2. Biological Controls:
    • Nematodes: Beneficial nematodes (e.g., Steinernema feltiae) can be applied to infested areas. These microscopic worms infect and kill leatherjackets without harming other beneficial organisms.
    • Predatory Insects: Encourage natural predators such as birds and beneficial beetles by providing habitats that support their populations.
  3. Chemical Controls:
    • Insecticides: In severe infestations, insecticides may be necessary. Products containing active ingredients like chlorantraniliprole can be effective. Always follow label instructions and consider environmental impact before application.

Best Practices for Turfgrass Growers

  • Regular Monitoring: Establish a routine monitoring program to detect early signs of leatherjacket activity. Sampling soil in suspected areas can help determine the extent of infestation.
  • Integrated Approach: Combine cultural, biological, and chemical controls for a more sustainable and effective management strategy.
  • Record Keeping: Keep detailed records of pest activity, control measures used, and their outcomes. This information can help refine management strategies over time.


Leatherjackets pose a significant challenge to turfgrass health, but with a thorough understanding of their lifecycle and an integrated approach to management, turfgrass growers can mitigate their impact. By staying vigilant and employing a combination of cultural, biological, and chemical controls, the turfgrass community can maintain healthy and resilient lawns, sports fields, and golf courses. The only chemical control currently available to turf growers is Acelepryn which contains chlorantraniliprole. This is only allowed to be used on 10% of the growing crop of turf. It is very high cost also makes it prohibitive for turf growers to use other than in exceptional circumstances. Homeowners can have this product applied to the whole of their lawn by a professional spray operator if needed

The Turfgrass Growers Association remains committed to supporting its members with the latest research and best practices for managing turfgrass pests.