Crane Fly Larvae and Turf Damage

Crane fly larvae, commonly referred to as grubs, live in the upper layers of soil, where they feed on grassroots and plant material. Their presence is most prominent in spring and autumn, and their activity can lead to fragile ground and poor turf condition. Public lawns may become difficult to maintain without proper control.

Detecting Larval Activity Quickly

Identifying larvae before serious damage occurs is beneficial. Watch for signs such as bird pecking, patchy grass, and irregular surface wear. Cut small patches in the turf to check for larvae beneath. Conducting these checks during early spring supports better planning.

Seasonal Risks to Grass Condition

Leatherjackets can continue feeding underground during milder winter spells. If they are not kept in check, the turf’s ability to recover in spring is hindered. Maintenance scheduling based on known behaviour helps reduce pressure on affected areas.

Physical and Mechanical Solutions

Maintenance teams often begin with physical practices. Regular aeration encourages root growth and improves turf firmness. Raising mowing height during feeding periods can reduce stress, and rolling moist turf may disrupt larvae, leaving them open to natural predation. These approaches help maintain turf quality, even if they do not fully eliminate the pests.

Natural Solutions

Nematodes, microscopic bioagents, offer a chemical-free way to address larvae. They are most effective when applied during early autumn, under appropriate moisture and temperature conditions. When timed and applied correctly, they reduce larval numbers and allow the turf to stabilise.

Supplementing with Registered Products

In some cases—especially on high-demand surfaces—chemical treatment may be necessary. Registered turf protection products may be applied, but only according to regulatory guidance. Blending chemical input with cultural and biological steps preserves soil health.

Reducing Future Risk

To minimise outbreaks in future seasons, aim to improve drainage, support strong rooting, and maintain balanced nutrient levels. Monitoring turf after crane fly emergence in late summer helps predict larval activity levels for the months ahead.

Frequently Asked Questions

• When do leatherjackets feed the most?
  
  They tend to be active in greater numbers during cool and moist periods in autumn and spring.



• How can I be sure I have a problem?
  
  Cut out a section of turf and count the number of larvae beneath. This provides a practical population check.



• Can nematodes survive in cold soil?
  
  No. They require specific temperatures and soil moisture to be effective.



• Does mowing height matter?
  
  Yes. Leaving grass slightly longer during larval feeding helps support plant health.



• Why are birds damaging my lawn?
  
  Birds often scratch where larvae are present. Their behaviour can be an unintended clue of infestation.

Summary

Managing crane fly larvae benefits from a blend of early detection, well-timed treatment, and varied management strategies. By coordinating physical methods, biological control, and limited chemical use, turf conditions can be protected throughout the year.

Need professional help? Visit website ALS Contract Services for more information.