The big ones look sort of like potatoes except that they are all knobby and the smaller ones remind me of ginger root.

Difficult at that stage, but they remind me of calla bulbs. Would those be likely in your area?

I'm not sure Gyr. We're new to this area - north coast in zone 9. Looking online I can see that the bulbs are similar to calla bulbs. Would additional photos with the bulbs spread out from each other help with ID?

For me, unfortunately additional photo would probably not help. I've seen calla bulbs at that stage of maturity and growth, and they did have several characteristics of the callas I'd seen. But they could be bulbs I am not particularly familiar with at that stage of development, or that just haven't come to mind. Some real leaf growth might be necessary. Maybe some other members will have other identification ideas.

Could be Arum italicum, given that that bed appears to be nurturing invasives. It would be an odd place for Callas, being dry and shady.

I agree they do look a lot like Arum italicum tubers. But I would have thought the foliage would still be apparent at this time of the year. It certainly persists through winter in my climate!

They look an kinda like Jerusalem Artichoke.

No, not JA. Wrong shoots.

Thank you all for your help.

I can explain the odd location. The area that I'm working on turning into a garden has been used for discarding garden waste for years. Most of it has composted over time and the soil is gorgeous, but as I'm cleaning it out, I have come across various bulbs. Most I have been able to identify, but this one has me stumped. I guess I'll put in a pot and see what happens.

This old compost pile may also explain why I have an archangel problem as well.

Also, for the record, we just bought this house and I'm discovering all sorts of plants that I haven't seen before. Now that the old composting area is pretty much cleaned up, I plan to start a new one, but I'll be careful what I put in it.

OMGosh! This thread has just identified a plant that grows at our other house - Arum italicum!

It is the strangest plant. Sometimes it comes up during the middle of a January freeze and then it'll finish blooming, produce it's red berries, die back and come up again during the hottest part of August. There is no rhyme or reason to it's cycle.

I've wondered for years what it is and now I know!

Me again - after looking at photos of both calla lily and the arum italicum, I think these bulbs look more like the lily. It'll be interesting to see what they turn into. :)

I put in weeds that I don't like in my pile but I get to them before they seed.