Leatherjacket & Crane Fly Treatment

A Leatherjacket (larvae) is the child of the Crane Fly or Daddy Longlegs. The larvae are what causes the damage to your lawn my munching on the white roots of the grass. They are also a tasty treat to the local birds. Don’t panic if you see a Crane Fly or Leatherjacket, most lawns have them living there but without causing any apparent damage. In this topic we are going to talk about how to identify a leather jacket problem and how to repair the damages after having them.

How Do I Identify Them ?

The larvae are brown grubs around 2 to 4cm long and can be located just below the soil surface if you have them. Just make sure they are Leatherjackets and not Chafer Grubs, these will be a creamy colour and have an orange/brown head and have legs.

Even though having a few of these creatures in your lawn is no alarm for concern, it can come to a point where it becomes a problem. A way of knowing is when lots of adult Crane Flies can be seen from around late July to September, this is a good indication that it will be an issue in your lawn the following year. Another indication is lawn damage by the wildlife, birds will start sweeping down in search for them pecking at the lawn ripping grass and thatch out.

If you feel that you suspect a problem or maybe the issue your grass is dying back, all you have to do is peel back small patches of turf in different areas and if you notice any grubs (4 or more per square foot) then it is highly likely the lawn will be/get damaged.

How Do I Treat Them ?

The only form of treatment available today is a product which we are sure you have heard of and that is Nematodes. There used to be chemical pesticides for Leatherjackets but they are now discontinued and unavailable in the UK. The most common Nematodes product is “Nemasys J” which is a non-chemical product that will naturally control leatherjackets in grass and turf.

Damaging leatherjacket larvae are laid as eggs in lawns during August by the Crane Fly. The withdrawal of synthetic chemical insecticides means Nemasys J is now the best method to naturally control leatherjackets by using the beneficial parasitic nematodes in Nemaysy J.

The Nemasys J Nematodes enter the larvae and stops them feeding within three days of infection. The larvae then die within 10-14 days. The Nematodes complete their life cycle within the larvae, then enter the soil seeking more hosts, and so the pest control continues naturally.

These beneficial parasitic nematodes are extremely effective when used correctly and may be best used from the hands of a professional, if you do decide to attempt this yourself please consider the following:

• Need to be applied at the correct time during the grub development.

• There needs to be a certain level of soil moisture.

• Be the correct temperature.

• Need to be stored correctly.

• The Nematodes need to find the grubs to parasitize with otherwise they will die.

There is quite a lot of factors when applying Nematodes for them to be effective.

How Do I Repair My lawn After Treatment ?

When you get to the point that the Leatherjacket issue has been solved it can be a big sigh of relief. But unfortunately, the work is not over just yet due to the damage left behind.

As the larvae has been chomping away at the roots of your grass, this causes the blades to turn yellow or even die back completely. If you caught the Leatherjackets early you may just end up with a small patch of yellow/brownish grass, this should be easily repairable by using our Ultimate Spring/Summer Lawn Fertiliser which will boost root growth bringing the grass back to life. However in most cases you would be very lucky to get away with just a feed, Nematodes take time to work and when they do finally get the job done it can be too late causing serious die back to your lawn or even completely.

A good way of checking to see if grass will make it is by pulling the roots up, if this is an easy task then you are going to have to re-seed the area. Please see below the steps to take.

• Make sure to mow the area first, when you sow the new seed you will have to wait a while before you can cut again.

• You will need to remove the yellow and/or dead grass from the damaged area, you can do this with a good scarify which will also help loosen the surface of the soil for you.

• Apply top dressing to any areas if unlevel, rake the soil to be level with the rest of the lawn and sow the grass seed at the recommended rate (on the product page) and work the seed into the soil to achieve great seed to soil contact, this will really improve germination and optimal results. You can even apply a light layer of top dressing to just cover the seed slightly, this will also help with bird take.

• For even better results apply our A1Lawn Pre-Seeder Fertiliser (6-9-6) at 35g per m2 around 2 – 4 weeks after germination. What this will do is boost the root system and help the old and new grass incorporate better giving you a stronger lawn.

• If no consistent rainfall is present, make sure to water the area for around 4-6 weeks keeping the seeds moist.

If you are looking to sow new seed, feed your lawn or want any additional advice, please get in touch, we are more than happy to provide as much information as you need to achieve your lawn goals. You can contact us by phone on 08004118141 or by email at sales@a1lawn.co.uk.