Regenerative potential of Elymus farctus from rhizome fragments and seed

(1) Both newly-germinated seedlings and shoots from single-node rhizome fragments of Elymus farctus were able to emerge after experimental burial with sand at a depth of 127 mm, but not from 178 mm. (2) Multi-node fragments had a greater probability of emergence than single-node ones at any depth, and also could emerge from greater depths. (3) Inhibition between buds on multi-node fragments led to reserves being concentrated into a single dominant shoot. Distal buds were more likely to become dominant than proximal buds. (4) Nodes of rhizomes taken from the dunes at monthly intervals showed seasonal variation in their ability to produce roots and shoots under controlled conditions. This regenerative ability was inversely related to the growth of the parent plants at the time of sampling, and could be increased by supplying exogenous nitrogen as nitrate. Seasonal patterns were still apparent, however, and concentration of total water-soluble carbohydrate was implicated as a further limiting factor. (5) Multi-node fragments are more flexible in their response to burial, because the likelihood of viable shoot production is increased and buds and resources are conserved against the possibility of further disturbance, whereas seed germination is an all-or-nothing gamble.