I have no idea what that is but you'll get a lot more responses if you post this on the regular rose forum instead.

Thanks.
I looked at it closer. Had to dog out my plants :(
But turns out it was floral foam. I don't know why it was there.

I bet it is something like floral foam, something that holds moisture till the plant roots. I looks like The material they use when starting cuttings hydroponically called rockwool cubes. It just got a little uncovered.

I see dye back on a fe cut stems . Cut close to the main stem to prevent these.