Leatherjackets in lawn

[Oaksilver]

Hi all. I have an infestation of leatherjackets (larvae of crane fly) in a huge lawn that was seeded 2 years ago. They have completely decimated the lawn. There’s thousands of them on the tarmac beside the lawn every morning so I can only image what’s feeding in the lawn. The lawn is eaten back almost to bare soil with a few bits of grass left. I know they can be treated with nematodes but think it’s too late for that now. If I spread some grass seed and fertilizer will the lawn recover or any suggestions for what I could do. It’s a lost cause for this year but I’m afraid that if I reseed I’m just feeding them and I’ll have exactly the same problem again next year. The lawn is soaking wet now aswell because of the root damage.

We had same problem a few years in a large area, probably half of our front lawn. We ended up taking up all the turf (very hard work!) that was affected, to leave the little blighters exposed for the birds to eat, and then we re-seeded a few months later and all seems good now. I think nematodes only work at certain times of year, or in certain conditions as we looked in to it but decided it was not the greatest solution.

Thanks for that. It’s the stuff of nightmares here at the minute. My biggest fear would be to do all that and have the same thing happen again next year. I’d never heard of them before this week and always thought the grass on a lawn was safe from pests and no pesticide available to kill them. The lawn on the other side of the driveway is fine so far. No birds are going into that side of the lawn at all now. I know they will emerge as crane flies and leave the lawn in late summer but could lay eggs on it again. Had a lovely lawn for 2 years but I can’t even look at it now

Definitely apply nematodes asap to reduce their number, then again in autumn time. You need twice the quantity of nematodes in spring as the larvae are bigger and harder to kill. It's best to apply during a rainy period so that the nematodes get down into the soil and don't dry out.

We are still battling a similarly awful infestation, but their number are much reduced after 18 months of nematode treatments.

Ours haven't returned and it was about 3-4 years ago. We have lived here a good number of years, and have several large lawned areas and this is only instance so just hoping it's a one off. Must admit, it does make me a bit murderous with any daddy-long-legs I see!

It definitely does. I always thought daddy long legs were harmless. Think everyone of them for miles around must have laid eggs in my garden. Little did I know! It’s going to cost a lot for nematode treatment on area I have. Are newer lawns more prone to them. The other side of the garden has been left completely untouched. It’s been sowed a few years longer. Give me a slug any day of the week!

Our house is 1950's so lawn has been down for years so they obviously aren't fussy!

Yes, new lawns are more prone to them. I'm not sure why though!

We’ve just discovered we have this problem too. We saw craneflies around it and flying out of it probably last summer (?) but I had no idea about the larvae and we thought the dog was ruining the lawn by weeing on it. Then over the last couple of weeks we’ve been finding the leatherjackets on the patio, hiding under all the pots. I’m too scared to dig up a patch of turf as a tester to see what’s under there!

Just ordered some nematodes to treat it over the next few days (fingers crossed they arrive soon so I can put them down while it’s rainy). Like PPs our lawn is quite new, we had lovely turf laid about two years ago and it looked like Wimbledon centre court out there for all of a few months 😄

Let me know how the nematodes work for you. I’m not going to put them on until late summer. I put some fertilizer on part of the garden that’s starting to go patchy and yellow because of them to try and strengthen the grass roots. The rest of the garden is too waterlogged for fertilizer, put I can see some improvement were the grass is trying to recover. Other half thinks I might be seeing what I want to see. So going to wait for it to dry out and then aerate and reseed. Got aerator for the back of tractor mower. Is it too much too hope that the larvae drowned or that enough of them kamakazied over the curb onto the tarmac in search of fresh grass. Earlier in the week there were literally thousands of them on tarmac in the morning but much less the last few mornings.

Thanks @Oaksilver, I will do 😊 we’ve had a similar situation actually, lots fewer on the patio the last couple of mornings. They make my skin crawl but the dog loves them 🤢