Random plants on new allotment

[Darthcider]

I have dug a large part of my new allotment and started planting etc, but have random plants sprouting, I assume from previous owners.
There are potatoes, and what I think is bronze fennel, plus some as yet unidentified things.

Should I let them grow and see if they provide a meal or get rid of them?

My thought is to leave them, but any reasons not to?

[Cadalot]

You always get volunteer potatoes, and they can be eaten but it depends how much work you have to do on the rest of the plot and if they are in the way or not. The unidentified things could always be weeds

[Penellype]

Fennel does seed itself all over the place if left so you could be right about that. If you like it, keep it or move it somewhere where it isn't in the way. I'd dig the potatoes out - you don't know what variety they are or whether they had blight last year, and I wouldn't want to risk it.