Diamond back moth

[ACE]

First I've heard about it. Is it just an overblown news item?  What does it do? how do we stop it, etc etc. Perhaps our continental chums have had dealings and can advise. Or perhaps it's just another fantasy of the In/Out mob.

[ACE]

[squeezyjohn]

I've had them and managed to identify the problem weeks ago before the news hit.  There's no way I can keep them off my brassicas as they're so small they can get through the debris netting!  However - I've been keeping an eye on them and I can't see any eggs or caterpillars on any of my leafy greens.

One article I read on them suggested that the caterpillars are susceptible to dying in prolonged periods of wet weather!  Well, they shouldn't last long if that's the case!

[ACE]

I'll just keep on spraying with my cheap washing up liquid then it seem to keep the other critters off. 'I'm forever blowing bubbles' is our usual after dinner anthem anyway.

[Beersmith]

Good afternoon Ace,

I spotted a very few about a week ago and rather more this morning, all in the patch where my brassicas are planted. They are smaller than I expected, but unmistakable. No signs of any major damage as yet. My calabrese and cabbage are actually looking very healthy. But I have some blemishes appearing on the leaves of my brussels.

I have no experience of being troubled by this particular pest before, so for anyone who is reading and knows more about these critters, what signs of damage can I expect to see? Any obvious symptoms, and any ideas on how to fight back? I avoid insecticides whenever possible, but very rarely I will use something like pyrethrum in an absolute emergency.

Cheers

Beersmith

[Obelixx]

There's some chat about this on the GW forum and one poster gives a link to more info - http://www.gardenersworld.com/forum/wildlife-gardening/diamond-back-moth/983455.html   Still not seen any here in rural, central Belgium.

[picman]

Is there anything that kills them, my purple sprouting today, also on sprouts , cabbage , caulie !!!!!!  ( North Worcestershire)

[squeezyjohn]

Is there anything that kills them, my purple sprouting today, also on sprouts , cabbage , caulie !!!!!!  ( North Worcestershire)

fingers?

[ancellsfarmer]

Is there anything that kills them, my purple sprouting today, also on sprouts , cabbage , caulie !!!!!!  ( North Worcestershire)

Try, (but no liabilty accepted !), in varying concentrations:
Brine,table salt( Na Cl3) in solution, possibly with Bicarbonate of Soda ,or
Detergent such as Fairy Liquid,( which probably contains salt)or
Methylated spirits , alcohol (but contains Methanol 5%). Most insects can be broken down in alcohol, especially wasps!;or
Citric acid, vinegar(acetic acid), formic acid(possibly by using "ant tea")
Many "recipes" on line, just ask Uncle Google.

[ACE]

One article I read on them suggested that the caterpillars are susceptible to dying in prolonged periods of wet weather!   

I can't see many of them lasting after last nights monsoon. The thunder and lightning should have also given them fair warning.

[Crystalmoon]

My turnips have been plagued by these moths this year for the first time ever & they got in through the debris netting as they are so small. So far I haven't seen massive damage, which I was expecting as there were so many of them. Here in Kent the rain has been torrential & often so perhaps that is why the damage isn't that bad. I haven't seen the caterpillars yet though so perhaps the destruction of my turnips is on its way 

[Crystalmoon]

Hi everyone I was able to harvest some turnips yesterday & they are fine, the leaves are shabby but the actual turnips are good. That was from the first bed so quite early sowing. I thinned the 2nd bed & didn't find any caterpillars or Diamondbacks, will have to see if the 2nd bed gets devoured by caterpillars. I won't spray anything on them. I have taken the netting off to let the birds at the caterpillars (in theory) so will see how things progress.

[Crystalmoon]

Hi everyone just wanted to update that I was able to harvest all of the turnips ok despite the mass invasion of these moths.
I haven't actually seen a single caterpillar which really surprised me. Where have they gone??????
Normally I would sow more turnip seeds in this raised bed as I had intended it to be the turnip bed for this year but just to be on the safe side I won't put anymore brassicas in this bed this year. Will probably stick some leeks in it.
I haven't seen any of the moths for at least 3 weeks now but was definitely expecting to see lots of the caterpillars. May be the torrential rain killed them off??? Or the birds took them once I took the netting off the bed???
I will have a really good dig about in the soil before I plant anything in the bed just to be sure its free from these nasties.

Has anyone else had loads of moths but no caterpillars?
xJane

[squeezyjohn]

I have found caterpillars of the Diamondback moths.  They are much much smaller and less destructive than cabbage white caterpillars and there also seem to be less of them.  They often don't leave complete holes in the leaves, rather they leave patches of damaged leaves where it seems they have just scraped the leaf leaving a brown/grey dead spot.  When they mature, they don't make a normal chrysalis, but instead spin themselves in to a little web in an indentation on the leaf - easily confused for something a spider could make.  Even at their biggest they don't get bigger than a large grain of rice.

I only found mine after cooking some broccoli!  They were everywhere in the florets and it was pretty disgusting finding all these cooked caterpillars.

[ancellsfarmer]

I have found caterpillars of the Diamondback moths.  They are much much smaller and less destructive than cabbage white caterpillars and there also seem to be less of them.  They often don't leave complete holes in the leaves, rather they leave patches of damaged leaves where it seems they have just scraped the leaf leaving a brown/grey dead spot.  When they mature, they don't make a normal chrysalis, but instead spin themselves in to a little web in an indentation on the leaf - easily confused for something a spider could make.  Even at their biggest they don't get bigger than a large grain of rice.

I only found mine after cooking some broccoli!  They were everywhere in the florets and it was pretty disgusting finding all these cooked caterpillars.

At least you know what they fed on!, and that those at least will not come back and breed again.

[Crystalmoon]

Oh my goodness Squeezyjohn how awful having all those cooked caterpillars!!!! Perhaps they are so small I haven't noticed them on the turnip leaves I discarded as I harvested. I composted the turnip leaves so I expect I will find out if I've got a Diamond Back nursery in my compost bin if a cloud of them fly out when I open it...don't think it's hot enough for the compost bins to fry them. Jane