[blackberryjam]

What weed is this ,it's  spread all over our allotments this year apparently it started with some manure someone got from a farm,
What is the best way to get rid of it

[mumofstig]

I think it is common Speedwell, aka Veronica arvensis.

Just hoeing it off should get rid of it, it's an annual so shouldn't grow back again once the tops are hoed off.

[Hobovore]

Speedwell is actually edible, I let it grow and harvest it for the flowers. I have known others that grow it as a flower in bedding.