is this something I'd want to keep? 2

Not sure,Fran,but it looks as though it could be a sucker from your Rose..If so,it needs to be cut off as near to the root as you can get,by scraping some of the soil away,to trace it back,if possible...I could be wrong ,but that's what it looks like to me..

thanks Bloomer. I did wonder if it was an offshoot, but the leaves re different shapes and colours, and the stem is smooth, no thorns. Of course it could be a juvenile

Mine were the same Fran..a much paler green leaf,and it sounds very much like a sucker,with stronger growing stems than the others..they would just take over,eventually..

I took some pics today of small stems of each, showing leaves and leaf layout on the twig. They don't look at all alike - different shape, colour and distribution on the stem. But the rose bush is flowering more than ever, so taht's the one I want to keep and protect. If I can get this interloper up and out with minimaal disturbance, i'll try planting it somewhere else to see how it turns out. but if I have to choose between it and hte rose bush, no contest!

I think it might be a well grown Mahonia seedling Fran. Birds love the berries and pass them through and the seeds can land anywhere. I have pulled up several much smaller ones recently. They can grow ENORMOUS. The ball is in your court. The rose is pretty.

thanks Dorjac. Think i'll see if I can lift it and put it somewhere where it'l have more space, and give the rose some room, too