what is munching on my broad beans???

[salome2001]

Damage just appeared overnight... lots of mine and lottie neighbour's broadies got munched. I suspected blackfly earlier in the week and sprayed then all with fatty acid spray. They now have a mild infestation of greenfly (and some ants), but this looks more like vine weevil damage to me???? Any suggestions (and ways to stop it?)

are these the culprit??

[VirginVegGrower]

It'll be that pea and been weevil again, if the edges are frilly. Nothing to worry about. They nibble notches in the leaf edges.

[salome2001]

vvg, I've learnt something new. Now to google ways of getting rid of them... I think "locating the weevils and squashing them" is a bit unrealistic for allotment broadies...

[salome2001]

and it appears it's not just me!!!
Pea and bean weevil notching activity likely to increase | News | Farmers Guardian

[zazen999]

If you'd have just left the suspected blackfly then the ladybirds would come along and have them as their breakfast after hibernating. This is the problem, when you spray for one thing you often kill off or ward off the potential good dudes that would do the work for you.



If you know you have them, check any saved seeds for holes and destroy them as they can live in the seeds; and fleece any areas after you have sown them, or grow plants in modules and plant out when older and stronger. Unless it is a complete infestation, they won't do too much damage to the resulting beans - and as they burrow down I'd suggest burning the roots of the affected plants rather than composting them.

Don't use vetches as a green manure and you could grow a sacrificial crop of beans in an affected area and once you see signs that the weevil are active, chop the lot down and burn in situ to try and kill off the adults so that they don't lay any more pupae.

[lottie dolly]

we always get it on our site,i noticed it on a plot near ours,i will have to give my home made sprays a try this year,already have a grand brew from last season,peeps say it will not effect the beans,but i beg to differ,so my babies are getting a treatment this morning,

[Two_Sheds]

Zaz, can't read your link, it's only for members

here's another: http://www.thewcg.org.uk/curculionidae/0297.htm

Sitona lineatus (pea leaf weevil aka pea & bean weevil)
"small oval eggs are laid in the soil from April to July ... larvae make their way to the root nodules upon which they feed"

"One adult female may lay between 500 and 3000 eggs, which are scattered upon the soil surface as she feeds" Ugh! I had one in my car

source

Control?
"Ground beetles (Coleoptera: Carabidae) account for variable, but occasionally considerable, predation of adult pea leaf weevil in England"
"Survival of young larvae, in particular, is decreased by warm and dry conditions" ~ they prefer cool damp conditions.

The larvae bury themselves about 15-27cm below ground, so it's pointless trying to hoe/dig them out: they don't do all that much damage anyway. They pupate about 7cm under the soil, and the adults overwinter on any legume around: alfalfa, clover, vetch, winter broadies, field beans etc.

The adults though, can potentially totally defoliate young pea plants, killing them. Keeping your peas well watered & fed, or growing them in the gh then transplanting them, is the best way to help them survive weevil attack.

It's pointless trying to kill the adults on the lotty, because more just fly in from neighbouring plots.



source

[salome2001]

thanks for the advice, The broadies are actually pretty robust- they were planted in November (Aquadulce) and the plants are a good 4-6 inches high. Got the beans from the allotment shop so I suspect everyone on the plot (especially the Old Boys) who have a massive broad bean section will be affected. Will bin the rest of the beans though, the thought of weevilly beans is not pleasant. Will definitely burn the plants too.

I don't even like broad beans. I only planted them because I took on the plot in October and they were the only green thing I could plant at that time of year

[VirginVegGrower]

I don't bother about these as they don't eat the crop, just frilly notches on your leaves. They almost make them look pretty!!!

[salome2001]

BTW, now I'm now worried about my peas... no notches seen but they're across the plot from the broadies. I have Meteor planted currently and more of these and some Kelvedon Wonders in the conservatory poking their heads out of rootrainers. Transplanted at about 6-8cm high after hardening off in the coldframe. Should this be sufficient for them to survive an attack??

[zazen999]

Did you read any of the link that two-sheds put up?

[VirginVegGrower]

BTW, now I'm now worried about my peas... no notches seen but they're across the plot from the broadies. I have Meteor planted currently and more of these and some Kelvedon Wonders in the conservatory poking their heads out of rootrainers. Transplanted at about 6-8cm high after hardening off in the coldframe. Should this be sufficient for them to survive an attack??

I always got these little blighters in both my beans and peas - fret not! They don't affect you harvest.

[salome2001]

Did you read any of the link that two-sheds put up?

yes, especially the bit about killing young pea plants. So my question is: at what stage should they be hardy enough?

[salome2001]

I always got these little blighters in both my beans and peas - fret not! They don't affect you harvest.

thanks vvg... I really want my peas to do well. Last year's container grown ones did pretty poorly.

[Two_Sheds]

Will bin the rest of the beans though, the thought of weevilly beans is not pleasant. Will definitely burn the plants too.

The weevils don't live in the beans. The larvae eat the roots and pupate in the soil. The adults eat the leaves and live in foliage of legumes. At no stage do they live in the bean itself: that's a different bug - the bean seed fly

at what stage should they be hardy enough?

They need to be hardened off properly (7-10 days outside daytimes, under cover at night). Don't grow them too soft: don't pamper them with too much water or feed, it will make the foliage softer and more prone to attack

It's impossible to say a preferable size for planting out: but for me, I'd go for 12cm tall bushy plants if pea weevils are about