Tried Dr M’s Poaceae quiz? If not have a go here… then check the answers below…
Some common grasses can be ID’d quite easily e.g. Dactylis glomerata (Cock’s-foot) which can often be reliably identified from 100 paces and definitely a species to ID from a moving vehicle at speed!
Other grasses can only really be ID’d to genus from a photo and some only tentatively even so.
But you can learn a lot from looking at plant photos as well as leafing though ID books (pardon the pun!) and of course walking through grasses in the field.
Check out Dr M’s review of the top books for grass ID here.
Stace, Cope & Gray, Hubbard and the veg key all have a role to play in polishing up your grass ID, whether in flower or vegetative you know its worth it!
So now, without further ado, here are the images all labelled up with common names and see the table below for Tribes, Latin names and ID hints and check out Dr M’s series on the Tribes of grasses (Tribes without tribulation here) for more top tips.
Poaceous Post Script: Thanks to those of you who pointed out the original image of #27 Marram contained at least some Lyme Grass (Leymus arenarius), the replacement photo is by Peter Gateley and is a classic unambiguous shot of Marram!
Thanks to the following for use of images:
Dr M says: Here’s the table, do send me comments and your top tips for grass ID!
|Tribe||Latin name||Common name||ID Notes|
|1||Poeae||Cynosurus cristatus||Crested Dog’s-tail||One-sided spike-like inflorescence, separate sterile and fertile spikelets, check them out with hand lens, they are awesome!|
|2||Aveneae||Aira praecox||Silvery Hair-grass||Annual of dry sandy places, inflorescence a delicate panicle, spikelets with dorsal awns|
|3||Poeae||Briza media||Quaking Grass||Elegant grass with drooping, purplish, ovoid spikelets “quaking” in the breeze|
|4||Bromeae||Bromus hordaceous||Soft Brome||Brome grasses generally have oval spikelets, lemmas with terminal awns, plants hairy|
|5||Poeae||Poa trivialis||Rough-stalked Meadow-grass||Inflorescence branches in whorls, spikelets oval, flattened and without awns (Festucas are similar but have awns)|
|6||Nardeae||Nardus stricta||Mat Grass||Stiff wiry grass, inflorescence a 1-sided raceme with 1-flowered spikelets|
|7||Aveneae||Arrhenatherum elatius||False Oat||Tall grass, inflorescence with clustered branches, irregularly triangular in outline, lemma with dorsal, geniculate (bent) awn|
|8||Aveneae||Agrostis capillaris||Common Bent||Inflorescence is a very fine branched panicle, 1-flower per spikelet. Inflorescence rather open in A capillaris while A stolonifera is more dense and compact|
|9||Aveneae||Phleum pratense||Timothy||Inflorescence a rigid, spike-like panicle, spikelets 1-flowered and glumes with a pair of horn-like awns (check close-up).|
|10||Aveneae||Phalaris arundinacea||Reed Canary-grass||Tall grass of wet places, inflorescence chunky and lobed a bit like an elongated Dactylis|
|11||Cynodonteae||Spartina anglica||Common Cord Grass||Salt-marsh grass, culm with several spikes – like the fingers of a hand, spikelets pointed and 1-flowed, ligule a fringe of hairs (but can’t see in the photo!). Check Hubbard’s book on grasses for the fascinating story of the evolution of this grass in the late 19th century|
|12||Poeae||Catapodium rigidum||Fern Grass||Stiff, glabrous annual grass of dry places, panicles one-sided and rather dense|
|13||Poeae||Festuca rubra||Red Fescue||Fescues have oval spikelets which are laterally compressed and usually with short terminal awns (unlike Poa). F rubra is rhizomatous (F ovina is tufted and not creeping) and you can guess the creeping habit from the photo, this is a coastal type which can be quite small and spiky|
|14||Poeae||Lolium perenne||Perennial Rye-grass||Characteristic of improved grasslands, inflorescence is a spike-like raceme and spikelet are oval and arranged edge-wise and alternate on the rachis (unlike Couch grasses which have spikelets arranged flat-side on)|
|15||Triticeae||Hordeum murinum||Wall Barley||Barley-like grass with spikelets long awned and arranged in threes (trios) well worth checking out with the hand lens. A very common annual grass of waste ground and the dog zone by lamp posts etc!|
|16||Aveneae||Glyceria maxima||Reed Sweet Grass||This is a big grass of wet places and the inflorescence is a dense and much-branched panicle and the spikelets are narrowly oblong. The leaves of most species have cross-veins which are worth checking out on a live specimen, obviously not visible in the pic!|
|17||Poeae||Puccinellia distans||Reflexed Salt-marsh-grass||Tufted perennial of salt mashes and salted roadsides, inflorescence is branched panicle with whorls of branches, the lower ones deflexed (pointing down), spikelets narrowly oblong|
|18||Arundineae||Danthonia decumbens||Heath Grass||A densely tufted rather small grass usually of acid places but also chalk downland, inflorescence is a compact panicle and the spikelets are plump and chunky. The ligule (as all grasses in this tribe) is a fringe of hairs (but can’t see in the photo!)|
|19||Aveneae||Deschampsia cespitosa||Tufted Hair-grass||Densely tufted grass with long inflorescence stalks and open branched panicles of silvery spikelets with lemmas bearing dorsal geniculate (bent) awns, leaves are coarsely ribbed (can’t see this in the photo).|
|20||Poeae||Dactylis glomerata||Cock’s Foot||Characteristic common grass, inflorescence a branched panicle with close-set branches and spikelets in dense 1-sided clusters, vegetative characters include flattened sheaths and conspicuous whitish ligule (cant see these in the photo!)|
|21||Brachypodieae||Brachypodium sylvaticum||Wood False Brome||Hairy grass not unlike a brome (hence common name) inflorescence is a spike-like raceme, spikelets are cylindrical alternating in 2 rows on opposite sides of the axis. Common grass of woodland and shady places|
|22||Aveneae||Lagarus ovatus||Hare’s-tail Grass||Beautiful softly hairy annual grass, does what it says on the tin, i.e. Looks like Hare’s tail! Lemmas have dorsal geniculate (bent) awn|
|23||Bromeae||Anisantha sterilis||Sterile Brome||A brome with spikelets elongated, lemmas with very long terminal awns, very common weed of arable and waste places|
|24||Arundineae||Molinia caerulea||Purple Moor-grass||Densely tufted tussock grass with long inflorescence stalks, spikelets often purplish. Up close you can see ligule a fringe of hairs (but can’t see in the photo!)|
|25||Aveneae||Polypogon viridis||Water Bent||Inflorescence branches in whorls and crowded with pale green or purplish spikelets mostly right to the base. A non-native species rapidly increasing in Britain|
|26||Aveneae||Melica uniflora||Wood Melick||Delicate attractive woodland grass, inflorescence loose and sparingly branched with 1-flowered spikelets (usually also with several sterile lemmas within)|
|27||Aveneae||Ammophila arenaria||Marram||Classic tufted grass of sand dunes, leaves inrolled to conserve water in the xeric dune environment|
|28||Paniceae||Echinochloa crus-galli||Cock’s Spur||Untidy, chunky spikelets, no ligule (but can’t see in the photo!)|
|29||Aveneae||Koeleria macrantha||Silver Hair Grass||The elegant, dense spike-like panicle and silvery green or purplish spikelets are characteristic, the leaf blade is narrow and densely hairy and ribbed, but can’t see in the photo though!)|
|30||Triticeae||Elymus repens||Couch||A grass with clasping auricles (Can’t see in the photo though!), inflorescence spike-like raceme with oval spikelets arranged flat-side on and alternating (unlike Lolium which has spikelets arranged edge-wise on)|
|31||Aveneae||Holcus lanatus||Yorkshire Fog||Softly hairy grass, inflorescence a dense panicle, spikelets papery and often purplish. Key vegetative character is the sheath with “purple striped pyjamas”!|
|32||Arundineae||Phragmites australis||Common Reed||Our largest grass, and abundant often dominant in wet places and swamps. Inflorescence erect and dense and much branched, spikelets with hairy axis. Ligule a fringe of hairs (not seen in the pic!)|
|33||Cynodonteae||Cynodon dactylon||Bermuda Grass||Inflorescence digitate (finger-like), ligule a fringe of hairs (but can’t see in the photo!). An uncommon grass in Britain, probably Archaeophyte and now established in sandy maritime places in SW Britain, also in the lawn at Kew and in Dr M’s garden!|
|34||Aveneae||Alopecurus geniculatus||Marsh Foxtail||Inflorescence narrowly cylindrical and spike-like, spikelets have lemmas with dorsal geniculate (bent ) awn. Vegetative character is the inflated sheath (typical of the genus) and geniculate culms (bent at the nodes)|
|35||Aveneae||Anthoxanthum odoratum||Sweet Vernal Grass||Inflorescence is dense and spike-like, spikelets are pointed and lemma with dorsal geniculate (bent) awn. Early flowering grass, sweet smelling when picked, hairy and sometimes purplish at junction of blade and sheath|
|36||Aveneae||Calamagrostis epigejos||Wood Small Reed||A tall tussock-forming grass of open woods on heavy soils, inflorescence a dense panicle, spikelets densely clustered. Calamagrostis spp have a tuft of hairs in the spikelet (not visible in the pic!)|