Feather-grass

Feather-grass (Stipa), a genus of grasses remarkable for the long awns which give a peculiar and very graceful appearance to the species, mostly natives of warm temperate climates, and including Esparto (q.v.). S. pennata, S. capillata, and S. elegantissima are favourite ornaments of gardens. When gathered before the seeds are ripe, its feathery awns remain attached, so that the tufts retain their beauty throughout winter. The feathery awns not only assist in the diffusion of the seed, which is carried by the wind to great distances, but in a very interesting manner help to fix it in the soil. Being very hygroscopic, the awn lengthens or shortens with each change of moisture, and each lengthening thus tends to push the sharp pointed grain a little into the earth, its return being prevented by barbed hairs. The awns are hence sometimes used to make rough hygrometers.