Crested hair-grass is a compact tufted perennial grass with narrow green to grey-green leaves. Its neat clustered heads are borne up on short stems usually only reaching about 40cm in height. The grass flowers are quite attractive, silvery greenish or purplish in colour and glistening when fresh.
Crested hair-grass is most often found in dry grasslands on infertile, often rocky or stony substrates. It is most characteristic of calcareous limestone and chalk grasslands, but also found growing in other base-rich grassland on screes, rocky outcrops, cliff-tops and sand dunes.
It is slow growing stress-tolerant grass that rarely becomes a major or dominant component of grassland communities. it is a drought resistant plant and is also able to colonise bare ground from seed after summer drought.
Crested hair-grass seed can be sown at any time of the year when soil conditions are suitable. It will take some time to establish mature plants from seed.
It is a slow growing grass that is able to survive well in stressed environments. It is a particularly useful grass for sowing onto green roof schemes where drought and nutrient stress would be limiting to other grasses. It does however lack the vigour needed to compete with stronger growing plants on moist fertile soils, or to recover quickly from disturbance, frequent close mowing or hard grazing.
Crested hair-grass foliage is palatable to livestock but does not produce much growth. When growing on stressed substrates, such as on dry green roofs, it hardly produces enough growth over a season to warrant cutting.