Celery Leaf Miners on Parsnips

[Snow]

I've cut all the bad leaves off and chucked 'em, crawling lavae included. I expect there are one or two that I have missed though, and they have a short lifecycle apparently so more are bound to be present still.

Are there any organic means of treating them if they do come back?

[clod]

Yes, they can make a real mess of your snips.

You could try pyrethrum spray from the organic catalogue, but I find the most effective way is to cover them with veggiemesh. I guess you need to do this at sowing time tho before the miners have found them.

Good luck!