After ripening of the seed, the leafless flowering culms always die down.
Most die down to ground level in the autumn, some go back to a woody rootstock.
The stems and foliage die down in winter leaving a stout taproot.
They'll die down there in the grass, said the third lawyer, whose name I forget.
When they die down in autumn, the leaves should be placed loosely over the crowns, with their stems on top to prevent them being blown away by the wind."