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Leatherjackets are the larvae of Crane Flies, otherwise known as the Daddy Long Legs. These larvae cause damage to lawns by feeding on grass roots. This can lead to yellowing of the grass and patchy areas of lawn. Lawns will also suffer secondary damage when Leatherjackets are present, as animals such as badgers, or birds will attempt to feed on the larvae; and will rip up areas of lawn in the process.
Naturally and safely control your Leatherjacket infestation with our Leatherjacket Killer Nematodes, which are deadly to the Leatherjacket larvae but safe to humans, pets and wildlife. Dragonfli Leatherjacket Killer contain Steinernema species nematodes that enter the Leatherjacket larvae via a natural opening, like the mouth, and feed on the pest from inside it. A natural bacterium is produced by the nematodes inside the larvae, which kills it. Infected larvae will be completely broken down by the nematodes. The nematodes also reproduce inside the larvae, releasing more nematodes into the surrounding area.
For optimum control over Leatherjackets, we advise using two applications of nematodes each year, once in the spring and once in the summer.
You should closely monitor soil temperatures and the presence of the adult Crane Flies (Daddy Long Legs) to time these applications.
Leatherjackets overwinter in the soil and can be present from February, or even earlier in certain weather conditions. We recommend applying nematodes in the spring when Leatherjackets have been observed in the soil, and soil temperatures are above 10℃. As a very general rule, with such varying weather in the UK, this will be normally be between February to April. Ideally utilise a soil thermometer to accurately gauge this, as soil temperatures are different to air temperatures.
We advise a summer application based on the presence of the adult Crane Flies (Daddy Long Legs). You should apply your summer treatment approximately 10-14 days after seeing the adult crane flies emerge from soil. This should make applications most effective. This treatment should be applied usually between late August to early September. Summer applications are most effective as the soil is warmer which provides better conditions for the nematodes to locate the Leatherjackets.
Leatherjacket Killer Nematodes are supplied in four pack sizes:
The 25million pack will treat an area of up to 50m2.
The 50million pack will treat an area of up to 100m2.
The 250million pack will treat an area of up to 500m2.
The 500million pack will treat an area of up to 1000m2.
If your lawn has suffered severely from Leatherjacket damage, and the number of Leatherjacket larvae within the soil is high, multiple applications of nematodes will be required to gain overall control. Consider applying Leatherjacket Killer Nematodes every 2 weeks in the summer period.
Choose a humid or wet day to apply your Leatherjacket Killer Nematodes. Nematodes are UV-sensitive and will not survive long when exposed to bright, sunny conditions. Apply the nematodes early in the morning or early in the evening in order to utilise the optimum humidity levels. Avoid application in frosty conditions.
Soil temperatures should be above 10℃ for the nematodes to be active, if applying in the spring.
To increase the effectiveness of your nematode treatment, we always advise you spike and scarify the lawn before application. If there are bare patches or poor grass coverage, spiking the ground is particularly important. If grass thatch is thick, scarifying the lawn is vital in aiding the passage of nematodes into the soil. The lawn also needs to be kept moist for nematodes to penetrate the soil and reach the Leatherjackets.
See also our Nemaflo carrier which will help aid the movement of the nematodes in the soil.
1. First open and empty the contents of your 25 million sachet of nematodes into a bucket or container of 2.5 litres of water and mix thoroughly.
2. Next, fill your watering can (fit with a coarse rose), or sprayer (hand held sprayers should suffice, with filters removed, or, if applying our 50sqm & 100sqm packs, use the Nema Super Sprayer for optimum nematode application) with the mixed 2.5 litres of nematode concentrate and add another 5.5 litres of water so you are left with 8 litres of nematode solution.
3. Finally, spray your lawn with the nematode solution.
Continue to keep the lawn moist for up to 2 weeks after application. Repeat these instructions for an introduction of a second nematode sachet application 7 days after the first application. Repeat applications may be required for severe applications. Full instructions are provided on delivery.
You can store unopened nematode packs in a fridge but it is best to ensure you apply your nematodes as soon as possible for the best results.
Leatherjacket Killer Nematodes are harmless to humans, and safe to apply to edible plants.
To aid the recovery, and boost the repair of your lawn that has suffered damage, try our Lawn Grub Repair Boost. This natural biostimulant helps roots regrow, and aids new grass growth. This will help negate lawn damage, and the boost can be used in combination with nematode treatments. Treatments can begin as soon as grass begins growing in the spring.
Used it twice so far, seen a huge difference in my lawn, will be purchasing again this year
If the wasps arrived dead why would these work ? Two weeks no improvement...so ?
Put some on our grass in Spring, and got great results.... had less than 10 leatherjackets. Ordering again now to give it a top up
Just wanted to thank Julian and the team for the recent shipment of nematodes. They arrived in really good packaging with clear instructions on how to use. I put them down last night and will keep the ground moist over the next two weeks. Great service, thanks!. Will be ordering from you every year!
I tried other brands of nematodes in the past but kept seeing the crane flies come out in the summer. This year after applying this brand in mid Sep 2020. I haven’t seen them emerge yet. I will be looking closely to see if I need to apply another batch this year but this brand has made a notable difference to the previous years. Thanks!!