Grasses or Poaceae

Dactylis glomerata or Cocksfoot grass

The family of Poaceae (number 170, or  the last family in Stace’s  and most other modern Floras) has 5 Sub-families and 16 tribes. It is by far the largest family in the temperate world as grasses flourish in nearly every habitat!

Although Stace does mention many obvious non-natives which have naturalized in several places as well as crop plants which have been grown for many centuries.

Many people find grasses hard to identify and this is mostly due because of their small parts, which often need  be looked at through magnifying glasses and of course they are mainly all green.

However with a bit of practise and knowledge into which diagnostics to look for, they are not too difficult.

There is a good website with pictures you can find here:

A good flora is useful and I still like my old flora of grasses by C.E. Hubbard, which was first published in 1954. I’ve got a third edition reprinted in 1985.

Several grasses have altered names and to find the correct name we have to refer to Stace or an even more recent flora such as ‘Grasses of the British Isles’

The Poacea can also be mistaken with sedges and rushes which are related and in the same order of Poales but whereas the grasses have hollow stems the sedges and rushes have solid stems. For more info see here

Here below you’ll find several links to  floras  about grasses, sedges and rushes:

or fold-out card of grasses: About this publication here:

“Covering 30 species, this new fold-out chart should enable everyone to put a name to some of the most common species of grass found in Britain and Ireland. A special feature of this chart is a simple-to-use lateral key to enable users to make the quick identification quickly.

This chart is part of the FSC’s range of fold-out charts, designed to help users identify a wide range of plants and animals. Each chart is laminated to make it shower-proof and robust for use outdoors. Clear colour illustrations and text by experts in the subject make these valuable resources for all age groups”.

Apart from the fact that grasses are really beautiful and many can be grown as an ornamental plant in your borders, they are also useful, although not so much as you might expect for this large family.

Some  ornamental genera and species are

Avena (Oat Grass), Brachypodium sylvaticum, Briza (Quaking-Grass), Bromus spp.,  Calamagrostis spp., Deschampsia spp., Melica spp. (Melick), Molinia caerulea (Purple Moor Grass), Phalaris arundinacea and especially the Gardener’s Garters,  Sesleria spp., etc. Many of the above also have named cultivars which are extra ornamental. Grasses form an attractive in-between for the more loud, colourful flowers we grow in our borders.

En masse, mixed with native wild-flowers, most grasses are very attractive when in flower. Each habitat has its own particular dominant grass in combination with the native flowers. Many more people should experiment with leaving their lawn uncut, instead of going for boring, high-maintenance, short-cut lawns! it also won’t need any extra watering and feeding then, yet  another advantage.

The main grass used in standard turf however, Perennial Rye-Grass, is not very attractive. But if it often has other grasses as well such as the Meadow-grasses, Timothy & Crested Dog’s-tail.  This could slowly be improved adding ‘weeds’ which suit the locality. The turf for bowling greens and other short-cut purposes has more attractive grasses with the delicate flowers of the Fescues and Bents.

Main uses:

  • In our temperate regions it is the fact that they can grow in many habitats and are food for our herbivores.
  • They can protect the land from erosion especially on high ground where most of our trees have vanished over centuries, to make way for  sheep and people.
  • Phragmites australis (common reed) is important for thatching and grass roots stabilize the sod of sod houses. Reeds are used in water treatment systems, in wetland conservation and land reclamation in Afro-Eurasia. 
  • With our limited digestive systems we can’t really use the green parts as food.   I found a nice account of somebody who has tried eating grass in ‘Food for Free’ by Richard Mabey.


  • We can of course eat the grains of our domesticated grasses but the wild grasses are too fiddly to clean.
  • Two  species of Rye Grass are used mainly and extensively as grass for forage and our native Perennial Rye Grass (Lolium perenne) is also the main species used for our lawns as it is particularly hard-wearing as well as playing fields for sports such as football and rugby. Perennial Rye Grass and Italian rye Grass (Lolium multiflorum) are also cultivated grasses used for forage.
  • An interesting article about the use of scented grasses in Norway, especially the genera Anthoxanthum and Hierochloe can be found here:Also found a lovely article for (big) kids in Santa Barbara region of the U.S.A. about different World Biomes and this one is all about Grassland:

Medicinal use:

  • There are only a handful of native grasses according to Julian Barker in The Medicinal Flora of Britain and Northwestern Europe, 2001; namely: Darnel (Lolium termulentum) which is an Analgesic (= herb for relief of mild pain) as well as a hypnotic (= herbs that relieve anxiety and induce normal sleep without unpleasant after-effects).                                                                                                                Externally uses: A lotion made from a decoction (= a medicinal preparation made from a plant) was used for sciatic pain, a poultice for ulcers and sores and the powdered grains in a suitable base as a drawing ointment. Internally: powdered dried grain for headache, arthritic pain and sciatica. This remedy is probably not used any longer.

    Couch Grass or Twitch (Elytrigia repens). Gardeners are always surprised to learn of the esteem in which herbalists hold this safe remedy. As anyone knows, dogs and cats use the leaves as emetic. Herbal medicine is the only therapy (apart from preening in other primates which is also practised by animals). Those with an eye to a horse’s coat would do well to include the rhizome in with their feed.                                                                                                       Action: Diuretic  and Demulcent.Uses: Cystitis, urethritis, prostatitis, benign prostatic hypertrophy. Adjunct to the treatment of renal calculi.                                                  

  • Sweet Vernal-grass (Anthoxanthum odoratum)                               Action: Sedative. Anodyne and anti-inflammatory. Improves peripheral circulation (external use).                                                               Uses: Insomnia, especially when coincident with physical and mental exhaustion. Painful joints, muscle pain & stiffness, chilblains (as baths or compresses).
  • Common Reed (Phragmites australis). A decoction of the root is a forceful diuretic of use in febrile conditions. The plant is host to Claviceps microcephala that has the same alkaloid content as ergot.
  • Many uses for Reed are found on the Plants for a Future Database here
  • Also for Anthoxanthum  and Couch Grass:

Finally this is the section on grasses and in particular the worlds staple crops (slightly edited) found in ‘The Medicinal Flora of Britain and Northwestern Europe written by Julian Barker, Winter Press, West Wickam, Kent, 2001. Thought it was a really interesting account and I hope you find so too.

“Though not the largest in terms of number of species, no other single family has greater ecological dominance: grasses are estimated to make up the major part in over 20% of terrestrial vegetation.

The origin of agriculture stems largely from the gathering of wild grasses and, when allied to the domestication of forage animals, for which pastures may be sown, the stage is set for the almost inevitable dominance of agricultural/pastoral societies over those of an earlier hunter/gatherer mode.

This most ancient meadowland and hill-pasture is not a natural habitat at all; broad-leaved forest is the climax vegetation of the greater part of Northern- Europe, to which it would revert in time should we fail to survive.

No other plant family, then, has anything like the economic importance of the grasses. Most settled societies (civilisations) and some that are semi-nomadic are based upon staple foods that we have come to call cereals after Ceres the Roman goddess of agriculture.

In Western Asia and adjacent areas, Wheat  and Barley were the first crops to have been systematically exploited and were ground for flour at least 12,000 years ago. Early weeds of the first crops were Rye and Oats that, by the first millennium BC were cultivated in their own right. Sorghum, various Millets and Teff are the main cereals of Africa.

Rice was developed in Southeast Asia along with a Foxtail Millet and Proso and  Maize is indigenous only to the Americas and was the staple food of the civilisations of the warmer latitudes. Cultivation is thought to date from 7000 BC but is more difficult to date because of the senseless destruction of ancient artefacts and records motivated by a sense of theocratic superiority and fear. Not only has the world been deprived of one of its great heritage, but also archaeological reconstructions have been more difficult for lack of clues.

The cereals are annual grasses whose specialised fruit is harvested; the ‘grain’ is a structure where the fruit wall is inseparably fused to the seed which is not only starchy but has an unusual protein rich compartment, as well as oil. The Wheats are from species of Triticum.

Rye is in the genus Secale, the cultivated form of which is S. cereal. The plant is hardier than wheat and can thrive on poorer soils than wheat can, but it makes poor bread on its account of low gluten content.

Cultivated Barley may be considered as Hordeum sativum, but other names are also in use.

A great deal of our pasture and hay (and hay fever unfortunately) is composed of the Meadow Grasses (Poa), Cocksfoot ( Dactylis), the Fescues (Festuca) and Timothy (Phleum). Their grains have been used as desensitisers to the allergy reactions the pollen causes but there is no convicting evidence for the efficacy of this approach. Other cereals are Rice, African Rice, Finger Millet, Proso, Italian Millet and Teff (Eragrostis tef) and there are many other locally gathered or cultivated cereals throughout the world.

  • Cereals are also fed to animals and used to make beers and spirits.
  • Herbage grasses for grazing and for making hay and silage is an integral part of animal husbandry.
  • Other grasses provide roof thatching, walls and floor matting as well as writing paper.
  • Appropriate species of grass are ideal for stabilizing sand dunes and embankments. (Marram Grass (Ammophila arenaria and Leymus  being the main examples.
  • Then there is turf for all manner of sports, including contented sitting, and the ‘amenity’ crops on which sitting is forbidden!
  • Necklace beads and brush bristles also come from types of grass, as do clarinet reeds and edible bamboo-shoots.
  • Bamboos have some place in amenity horticulture in these latitudes and also provide the gardener with canes.
  • Cane sugar, from Saccharum officinale has for long been a cash crop, to the severe detriment of the land producing it and those who cut it and to the health of those whose sweet tooth has been catered for so lavishly.
  • With so much emphasis on the supply of starch, sugar and fibre from grasses, their evaluation for other compounds has been somewhat overshadowed.
  • Alkaloids are found in the family, as are saponins, phenolic acids and, especially in tropical forage grasses, lethal amounts of cyanogenetic glycosides.
  • Oestrogens are found in some of the temperate species. For all the diversity of the family, the herbalist is left with the following handful of plants. Nonetheless, Couch Grass and Corn Silk are certainly ones that it would be very difficult to go without.
  • Floating Sweet grass or Manna Grass (Glyceria fluitans) is an useful herbage in water meadows. Larger species provide cover for water fowl “.                                                                                                                                                                                                                                                      

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