What eats flea beetles

[Devil's advocate]

Flea beetle must have a predater.

What eats them?

I have some swedes & the best ones under net just getting 4 true leaves but taking some damage from the flea beetles, I'm reluntant to treat because cabbage root fly is the bigger problem & ground beetles eat the rootfly eggs.

 

[Kidds]

I don't know of any predators of flea beetle. They would have to be bigger than flea beetle as that is the general rule of predation, and there would have to be an awful lot of them to control any significant number. As the population curve of predators has to lag behind the prey curve there would be an awful lot of damage before predator numbers caught up.
A parasite, virus or disease would be a better hope. Do you think Bacillus thurungiensis has any role to play or do the flea beetle just come in from too wide an area?
I rely on predators controlling a range of pests in my orchards, I would never ever even consider using pyrethroids in there no matter what. They do more harm than good.

Are your nets not working then? Or are they not fine enough? I am using fine nets that are supposed to keep flea beetle out but it is my first time using and only on large garden scale.

 

[Humble Village Farmer]

Parasitic wasps lay eggs within the larvae (or maybe eggs within the eggs).

 

[Devil's advocate]

I don't know of any predators of flea beetle. They would have to be bigger than flea beetle as that is the general rule of predation, and there would have to be an awful lot of them to control any significant number. As the population curve of predators has to lag behind the prey curve there would be an awful lot of damage before predator numbers caught up.
A parasite, virus or disease would be a better hope. Do you think Bacillus thurungiensis has any role to play or do the flea beetle just come in from too wide an area?
I rely on predators controlling a range of pests in my orchards, I would never ever even consider using pyrethroids in there no matter what. They do more harm than good.

Are your nets not working then? Or are they not fine enough? I am using fine nets that are supposed to keep flea beetle out but it is my first time using and only on large garden scale.

Short staffed, main helper having cancer treatment.

So putting nets on was too slow. But flea beetles can slowly get through.

 

[Devil's advocate]

So can ground beetles eat flea beetles? Saw quite a few lady birds today.

Crop still holding its own. I also grow transplanted leaf veg which has been drenched with verimark only netted if we can't keep rabbits & pigeons off. We drill swedes in the tramlines & just use them for stockfeed. Sown some recently into perfect conditions & had perfect emergence, three days later flea beetle had the lot.

 

[Bogweevil]

Ground beetles or carabids are amongst the most abundant invertebrate predators in fields of oilseed rape in Europe. The immature stages of the six major pests of oilseed rape i.e., cabbage stem flea beetle, pollen beetle, cabbage seed weevil, cabbage stem weevil, rape stem weevil and brassica pod midge, are vulnerable to predation by carabids when they are in or on the soil from mid-September to mid-July. About 42 species of carabid are common in rape fields.

https://www.researchgate.net/public...nce_Spatio-Temporal_Distributions_and_Feeding

Parasitic wasps have a go:

How parasitic wasps could help farmers kill a problematic pest

Parasitic wasp larvae are among the natural predators which could help farmers kill a marauding crop pest in the absence of banned pesticides, said…

www.edp24.co.uk

Bats. Most TFF users are bats so it is surprising so many struggle with flea beetles.

 

[juke]

Parasitic wasps are csfb predator, you need something in there to attract them.
Other option cover the plants in diatemaceous earth.

 

[SJG]

Sheep. Grazed off two fields that looked well but had 20+ larvae count. Crop is now thick but not particularly tall. Will let you know how it yields.