Seedling growth in Elymus farctus after episodes of burial with sand

Episodes of burial by wind-blown sand are a frequent hazard for Elymus farctus in the strandline and foredunes. We have investigated the ability of seedlings to withstand and recover from experimental burial. The burial treatments were applied at the two-leaf stage, either for one or two weeks, and the growth in them was compared with that in unburied controls. The method of B-splines, with knots defined at the beginning and end of the burial period, proved to be appropriate for fitting relationships between In dry mass and time for growth analysis. The relative growth rates derived from these relationships were partitioned into component relative growth rates for individual plant organs, to reveal the responses to burial in terms of dry matter allocation.

No plants survived two weeks of burial but all those buried for one week recovered. There was respiratory loss of dry mass during burial, although fitted relative growth rates were not significantly different from zero. On re-exposure, relative growth rates increased to equal the maximum values in unburied plants. Dry mass losses were from the root and stem fractions. Leaf 1 was unaffected, whereas the development of leaf 2 was curtailed. Apart from their delayed appearance, leaves 3–5 behaved similarly to their non-buried counterparts. The maintenance of leaves at the expense of other organs during burial may be crucial to the survival of E. farctus seedlings.