Posted: 27/02/2015 at 22:52
Mulching helps a lot
The RHS says:
Creeping buttercup spreads by means of long runners; strong white, deeply penetrating roots that branch from each leaf node. Sub-lateral runners develop to form a vigorous, firmly anchored network of stems.
'Reproduction is usually from seeds but in moist conditions small nodal sections of stems may become established if severed and scattered when roots are beginning to form.'
Now that contradicts itself somewhat! Hunting around in the more formal literature I think I am happy to say that Creeping Buttercup can't regenerate from true roots, but can from a bit of the 'runner' [technically a stolon and for the RHS apparently a 'root' in the first paragraph and a 'stem' in the second!].
The stolon [another example is a strawberry runner] is green if it is growing in the light, but if it has pushed under the soil or is otherwise in the dark then it goes white.
True 'roots' are white and smooth; the stolon is hairy. True roots [of this species] lack the ability to make a new vegetative growth shoot, but the stolon has occasional leaf scales under which is a bud that can regenerate.