The Problem with Leatherjackets

Crane fly larvae, commonly referred to as grubs, dwell in the upper layers of soil, where they consume grassroots and plant material. Their presence is most prominent in moderate seasons, and their activity can lead to soft ground and poor turf condition. Managed landscapes may become unsafe without proper control.

Recognising Early Signs

Identifying larvae before serious damage occurs is wise. Watch for signs such as increased bird activity, patchy grass, and irregular surface wear. Cut test squares in the turf to detect larvae beneath. Conducting these checks during late winter supports better planning.

Seasonal Risks to Grass Condition

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

Tackling the Problem Without Chemicals

Groundskeepers often begin with physical practices. Regular aeration strengthens root growth and improves turf firmness. Raising mowing height during feeding periods can improve resilience, and rolling moist turf may lift larvae, leaving them open to natural predation. These approaches help improve turf quality, even if they do not eradicate the pests.

Natural Solutions

Nematodes, microscopic worms, offer a targeted 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 suppress larval numbers and allow the turf to recover.

When to Use Approved Chemicals

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

Avoiding Repeat Infestations

To avoid outbreaks in future seasons, aim to optimise drainage, encourage strong rooting, and maintain steady nutrient levels. Monitoring turf after crane fly emergence in late summer offers insight into larval activity levels for the months ahead.

Frequently Asked Questions

• When do leatherjackets feed the most?
  
  They tend to be present 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.

Main Takeaway

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 maintained throughout the year.

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