[Aeneas]

Some of my young peas - 6 - 8 ins high - are yellowing and falling over. When I inspected the stems I found a brown mark at soil level and the plants easily snap or pull out at that point. At first I thought it might be the result of damage done when I put them in or from subsequent windy conditions. (The plants were germinated in a polytunnel and planted out in a raised bed where I have not had peas or beans before). But it may be some kind of stem rot. Or is there a pea sawfly that would work its way across the bed? Any advice, diagnosis welcome.

[verge]

Sounds like a foot rot, sometimes you will have browing at the roots as well.
Worth pulling up one or two to see. If it is foot rot, then it is a fungal disease with no real cure save prevention of further pea infection by removal of the affected plants and the soil around their roots.
Any pictures to confirm?

[Aeneas]

[verge]

Good to hear. Not the damage, but that you are not infected.