flea beetles - wow!

[Jude]

I know you are supposed to catch these little darlings by brushing a piece of greased card or suchlike over the affected crop, but blimey, they are quick aren't they? Took the plastic cloche off a pristine row of rocket yesterday afternoon, by 10am today they looked like a lacy green scarf

[Nature's Babe]

Wasps are great predators of flea beetles, despatch them very quickly so it pays to tolerate wasp nests. Lacewings are also predators of flea beetles, live and let live works well for me. saves pounds spent on pest control.

[alan refail]

I can't say I've ever heard that wasps eat flea beetles. I should not have thought there are significant numbers of wasps around at this time of year, but it sounds as though Jude has a vast number of flea beetles!

[peter]

I've seen three wasp queens scraping wood this weekend, or the same one twice as a neighbour stood on the first. Definitely no worker wasps yet.
Had a bee swarm pass through though.

[Nature's Babe]

I guess we don't always see what is right under our noses alan, but it is mentioned here --

http://www.naphillhorticulturalsociety. ... 081208.pdf

we must be ahead of you here in the south east, there are wasps, hoverflies, solitary and bumble bees here,the self seeded land cress is flowering already and they were all visiting that patch yesterday, I had a pesky wasp dive bomb me when hanging out the washing yesterday!

[Elaine]

Up here in good old East Yorkshire, I've had a couple of wasps come into the house on the very few warmish days we've had. Lots of ladybirds, a few hoverflies, bumblebees and honey bees and a couple of peacock butterflies. A few unidentified micro moths have made it indoors too.

I notice the cold weather does not seem to affect aphids though...there is a thriving colony on my strawberry plants.

If the weather doesn't warm up soon, the birds will have a hard time feeding their nestlings, as the caterpillars they need will not be available.

[Elaine]

We had a severe flea beetle attack on the swede seedlings last year...they too ended up lacy.

[alan refail]

NB

Two quotes from your link:

Another example of a natural predator is that of wasps attacking flea beetles. I had a bad attack of flea
beetles on my brassicas and along came a wasp. You should have seen the wasp operate! It moved
quickly along the leaf and all the flea beetles in its path miraculously disappeared – the speed of the
wasp’s mopping up operation was faster than the human eye could detect.

Now to a real problem, or a real problem for me. The flea beetles seem to come
suddenly. One day there are none and the next day any members of the brassica family
(including radishes, swedes, etc) are covered in flea beetles. The only reasonably organic
remedy seems to be derris dust, which does work. However, it is the speed of the attack which
causes the problem for me. As an example, I sowed some swedes, spring cabbages and late
spring broccoli at the end of July, and watered the patch daily because of the extremely hot and
dry conditions. Up came the seedlings and all was well until they were about two inches high.
Then in one night they were grazed to the ground by flea beetles – completely wiped out. The
only solution I can think of to avoid that in future years is to puff derris dust along the row at
the time of seed sowing and repeat as necessary during the period of early growth. Flea beetles
do not seem to be around during the usual sowing period of March/April but sowings done in
the middle of the summer are at high risk.

[Johnboy]

Hi Alan,
I find both quotes to be extremely suspect.
The nanosecond a wasp touched a leaf a flea beetle would be off.
So I suspect it was a case of the quickness of the the flea beetles
that deceived the eye. Hence the rapid clearance. In my experience flea beetles like an unkempt plot, they live in uncleared leaf litter and mulched areas and especially the latter.
Would suggest that flea beetles will not completely eat a plant overnight it will leave your plant just like someone has loosed off a shot gun.
Both Slugs and Wood pigeons would be the more likely culprits to demolish the plants.
JB.

[Jude]

Thanks for your responses.
NB I do live and let live
Johnboy, my plot is extremely kempt! (Well, it is at the moment)

[Johnboy]

Oh Jude,
I was furthest from my mind to make it a reflection on you.
But that is what harbours flea beetles and we are having a bit of bother with then here. Not me but one of the people who has an allotment here.
Our plots are clear and well kempt but the little b---rs live in the hedgerow closeby.
They will be sprayed shortly (under a fleece). They seem to hunt enmasse and generally at night.
JB.

[Jude]

Johnboy, and I didn't for a moment take even the tiniest bit of offence, sorry if it sounded as if I had

[Nature's Babe]

Me too Jude, sorry, no offense intended, just trying to help. We have a woodland strip behind us, and leaf litter covers the garden in autumn, yet so far no flea beetles, the radish are fine. I find myself wondering what spiders trap at this time of year, there are loads of different spiders all over the garden, canny little buggers are usually found weaving webs among my cane fruit just before the fruit is ready to harvest, i guess they are setting a snare for the fruit pests as they zero in, so I try to pick the fruit without disturbing their handiwork ! LOL My garden is far from well manicured, there are log piles, three big compost heaps, usually some stuff sprawled flowering and ready for me to harvest seeds, I let weeds grow but not seed, then pull them and mulch or compost, and yet it's all very productive.

[FelixLeiter]

Wasps are everywhere already, but they're cryptic at this time of the year, stealthily going about their predatory business, rapidly and with purpose. It is often asked: what use are wasps? To which the answer is: they are an essential part of our ecology. It's only when the nest gets overcrowded come the end of summer and the queen leaves the nest, leaving all the workers aimless and confused, that they become pesky.

Up came the seedlings and all was well until they were about two inches high.
Then in one night they were grazed to the ground by flea beetles – completely wiped out.

I'm with JB as far as the seedlings getting gnawed to stumps is concerned: not flea beetles, something else. Usually slugs and snails attack at night, but in dry weather birds tend to attack seedlings to get a drink, which I think is a bit of a clue in this case.