To help grounds staff and volunteers prevent and combat leatherjacket infestations, the GMA’s regional pitch advisor, Simon Johnson shares his top tips to support the turf-care community with the issue.
Through its ongoing work, the Grounds Management Association has received reports of increasing numbers of leatherjacket infestations in the natural turf-care community, largely due to restrictions on chemical applications that can be used in turf-care. This, as well as a lack of correct grounds maintenance tasks, has led to an increase in ideal egg-laying sites for the crane fly.
But first, what are leatherjackets and why are they a problem for turf?
Leatherjackets are the larvae of the crane fly, more commonly known as the ‘daddy long legs’. They live in the topsoil layer of natural turf and feed on a grass plant’s roots and crowns. This feeding is an issue in itself for your turf as it stunts the growth of the grass plant, but there are other dangers that leatherjackets pose. Leatherjackets are a source of food for badgers, rooks and other wildlife species. The damage caused by these animals, when searching for leatherjackets in your turf’s soil profile, can be significant and costly to fix. This is why it is essential to minimise any chances of a leatherjacket infestation and to address it properly when one does occur. The following tips will help you to do just that.
Tip 1: Prevent infestation in the first place by avoiding thatch
As is the case with many things in life, prevention is often better than a cure, so carrying out regular grounds maintenance practices on your turf, such as regular aeration, a decompaction programme, and scarifying the turf surface to minimise levels of thatch, will all be effective ways of significantly minimising any chance of infestation in the first place.
This is because mossy, thatchy surfaces are ideal for female crane flies to lay their eggs in – by carrying out the above tasks regularly, you prevent the crane flies from being able to make a home in your turf and beginning the early stages of a leatherjacket infestation.
Tip 2: Know what to look out for
Knowing what to look out for with a leatherjacket infestation can help you spot the problem early and deal with it quickly, minimising any potential damage to your turf. A leatherjacket infestation can be spotted early by the yellowing of turf where the grubs have eaten the roots of the plant. Another key sign to look out for is when there is damage or interest in the turf shown by wildlife when searching for grubs.
Tip 3: If in doubt, get the tarpaulin out
The most important thing to do when the first signs of a leatherjacket infestation have been spotted is to confirm the size and scale of the potential infestation. Doing so will help you to understand the level of response that will be required. The best way to see how large an infestation will be is to cover your turf overnight with a black tarpaulin. Then, in the morning, you should uncover the turf and if there is any infestation, the grubs will have come to the surface. The grubs that have surfaced can then be collected by using a mower or by letting the birds remove them.
Tip 4: In a fight against leatherjackets, nematodes are your closest allies
Due to restrictions on the types of chemicals that can be used on natural turf, there are no chemical products available yet to the general public that can be used to deal with leatherjacket infestations. Because of this, when fighting a leatherjacket infestation, your closest allies are nematodes, a type of roundworm that will eat any leatherjacket grubs in the affected area.
This was the course of action that was decided when a leatherjacket infestation was discovered at Constantine CC. The nematode application worked brilliantly and within months, the cricket field looked fantastic again. Currently, only nematodes or the black tarpaulin methods for dealing with leatherjackets are available. The decision of which one to use depends on the area that needs to be treated. If you need advice deciding, you can get free help from our Turfcare Advisory service. Find out more about how to get in touch below.
Tip 5: Maintaining a healthy turf sward will help combat a leatherjacket reinfestation
So, you’ve successfully spotted and dealt with a leatherjacket infestation – good work. Now you can begin work to ensure your turf is healthy and to avoid any chance of a re-infestation. This is done by maintaining a healthy turf sward with regular fertilisation applications and a good decompaction and aeration programme. Doing so will help to limit the thatch levels of your turf, therefore making it more difficult for the crane fly to lay its eggs. This is the best, most effective way of protecting your turf from any leatherjacket reinfestation.
These tips have been produced by the GMA on behalf of the not-for profit organisation’s work with grassroots sports clubs. As part of the GMA’s support, you can read how Regional Pitch Advisor, Simon Johnson, helped a local cricket club, Constantine CC deal with a leatherjacket infestation to produce a better looking ground than ever before by clicking here.
If you, or anyone you know, is struggling with a leatherjacket infestation, or is having any other issues relating to grounds maintenance, then get in touch with our Turfcare Advisory, an easy-to-use service offering a wide range of advice, from basic playing surface problems to the design and construction of playing surfaces. For more information on the service, get in touch with our Learning team at firstname.lastname@example.org.
Our upcoming webinar, GMA Live - Integrated Pest Management looks seeks to provide attendees with the information needed to create and implement an Integrated Pest Management regime for natural turf playing surfaces at both a professional and amateur level. To register for the webinar, click here.
ICL is carrying out an important survey on Leatherjacket and Chafer Grubs in order to ascertain the size and severity of the issue facing grounds managers across the UK. The survey takes 2 minutes to undertake and any responses and identities will be kept anonymous. You can take the survey by clicking here.