What's munching my crops?

OK, so what's going on here?! I can't seem to grow much without something eating holes in it. I've just sowed some late mange tout and low and behold as soon as they showed themselves with a leaf or two they went the same way.

Generally, alliums are the only thing that they won't go for.

Does anyone know what it is and more to the point, how to control it?

 

Hi,

For the large leaves looks like catapillars damage, you will often find black droppings if its them.
Netting often needed for Brassicas and similar to stop the Butterflys.

Slug and snails for the smaller tender things, could also be things like mice or birds looking for quick snack.

 

Looks like slug damage.
You need summat that eats/kills/deters them.
I don't get caterpillars since i net all brassicas, but they are devastating when they strike.

 

Thanks for all the replies.

The big leaves are rhubarb but no sign of caterpillars!

For slugs, I use beer traps, which catch a lot but I've found that the traps need checking and re-filling frequently. Miss just one day when the beer is stale and wham, slug damage.

My Cavolo Nero is netted and doesn't have caterpillars or eggs on it so I'm guessing at some other veg muncher. I'm going to upgrade my netting defenses to something like Veggiemesh for next year.

I posted this thread as I suspect that some sort of leaf-mining insect is to blame. They must be very small if I am right. I've found slugs tend to start at the edge but the holes are right in the main part of the leaf. Any thoughts?

 

...sorry, it's Holes 1.jpg