eeeuw! It looks like some sort of gall - although I am only familiar with robin's pincushions and I think there are a couple of odd spherical ones which appear on the leaves. I am certain I would be stabbing at it with some sort of sharp object, see if there were nasty little larvae inside.

I am certain I would be emailing that photo to David Austin Roses and asking them what it is and looking for a new plant if it is indeed gall. You do not want to plant that in your garden where it could spread if it is diseased.

The usual gall on roots is crown gall, but that normally has a brain-like or cauliflower-like surface texture that is not apparent in the image. Crown gall is bacterial and infectious through wounds, so I wouldn't go stabbing at it until it is separated from the plant. If it has larvae inside, then no problem. If no larvae, then it could be crown gall and the wound plus nearby areas should be dipped in 10% bleach solution or treated with a copper fungcide. These are also bactericidal. Then sterilize tools.

Campanula, I agree, it looks like gall. Seil, contacting DA Roses was the first thing that I did.
Michaelg, what is it if it has larve?

Looks like gall to me.
I wouldn't plant it. If in doubt, plant it in a pot, and isolate it.

Jeri

I called DA Roses (in addition to the photo by email) and they will get back to me.

This rose was packed bare root with another rose in a plastic bag, no newspaper or anything around them, just the roses in the bag. Is the other rose also in danger?

Most galls other than crown gall are caused by insects (often tiny wasps) laying eggs in the plant tissue. These are relatively harmless. However, I never heard of them on roots. Crown gall can infect any part of the plant.

If it is crown gall (cauliflower-like texture), the other plant in the bag could have been exposed to the bacteria. Avoid wounding the bark. You could spray it with a bactericide, but chances are it will be OK anyway.

This bacterium is widely distributed and may already exist in your soil.

DA is replacing both roses. I guess I am out the $7 in potting soil that I will have to discard, but oh well...