clematis

I don't think so but layering works, and also cuttings if you are lucky.

What you can do is untangle one stem, lay it out, you then need to slightly 'damage' the stem at the nodes (when the stem produces leaves) - do this by gently twisting the stem until is splits a little but does not become detached - then peg the stem down into the soil (or pots of compo) at each of these places and keep them watered. I'm told this works, but sounds fiddly to me so never tried it! Good luck.

My montanas seed themselves - I have several 'babies' which are growing in the gravel or soil near their parent plants! Have a look - you might be lucky.