Crane flys & leather jackets
Leather jackets can potentially cause extensive damage to lawns. The Leatherjacket is the larvae of the Crane fly (Daddy longlegs).
Crane flies lay their eggs onto grass areas, including lawns from around September time.
When the eggs hatch into small larvae they will start to feed on the roots of the grass. At this stage the damage will be minimal, however by February/March when the larvae have grown they can cause severe damage.
To begin with you may notice bare patches appearing in the lawn. If you lift an area and it comes up easily you will know potentially it is caused by leather jackets or other similar grubs, such as chafer’s as they are eating away at the root system.
Further damage can be caused as birds and other animals root down looking for the grubs. The effects of this activity can be quite devastating causing severe damage to your lawn.
Treating Leather Jackets.
There are no chemical treatments on the market to control leather jacket infestations
If you see crane flies (Daddy Long legs) flying around the garden in September this is when they start to lay their eggs over a 2 to 3 week period. Consider increasing your mowing regime at this time. If you remove the grass clippings you will also remove any eggs before they hatch.
If you suspect an infestation you can encourage the grubs to the surface. Wet an area on the lawn and then cover with heavy plastic sheeting secure it down so it it airtight and cover for a couple of days. This process will bring any grubs to the surface, these can then be removed or left for nature to dispose of them naturally.
Nematodes are available on the market, these are natural parasites which attack the grubs. They are expensive to buy, difficult to store and complicated to apply.