The role of stolon internodes for ramet survival after clone fragmentation in Potentilla anserina

Stoloniferous herbs are common in disturbed habitats, where interconnected ramets frequently become separated by water, grazing animals or human activity. Stolon internodes serve as spacers and transport channels for resources, but they may also fulfil a storage function. We simulated physical disturbance and breakage of stolon connections in the stoloniferous herb Potentilla anserina, to test the hypothesis that juvenile ramets can survive clone fragmentation better if they remain attached to an internode after being severed from the rest of the clone. Juvenile, unrooted ramets were cut off from stolons with and without the preceding (basal) internode and placed on wet soil in a greenhouse. All ramets with an attached internode survived, while survival rates dropped to 37% for ramets from which internodes had been removed. The dry weight per unit volume of internodes decreased by about 20% during the experiment. We conclude that stolons are likely to fulfil a storage function that may be of ecological importance in disturbed habitats.