Following the successful field course at the Lizard, Cornwall, Dr M is currently taking his MSc students on a week of field days, visiting a range of sites and habitats not too far from Reading. Here is the first post from Dr M’s field day diary:
Day 1: Kicked off with a site very close to Reading, the University campus itself in fact! This was a day for botanical reorientation and consolidating knowledge of common plants, with a focus on Poaceae (a family of grasses green and wonderful!).
The first hour was spent outside on a small patch of grassland with a few spikes of Bee Orchis (Ophrys apifera) checking the common grasses and dicots there.
Then coffee time, always welcome, especially as today was thirsty work in the warm sunshine!
After coffee, Mrs Sue Mott (Deputy Curator of the RNG Herbarium), lead a workshop on how to make an herbarium specimen. One of the module assignments asks students to prepare a set of herbarium sheets on a selection of monocots (grasses, sedges, rushes etc; Dr M decided for the sake of the Bee Orchids to exclude Orchidaceae from this task!). Students were given top tips for producing beautiful and accurate herbarium sheets.
Then lunch! Also always a welcome event!
Then out into the University Meadows and Dr M emphasised that the focus of the day is on the important field botany skills: recognition and ID.
Recognition: The more plants you can recognise the fewer plants you need to regularly ID with plant keys etc.
ID: using keys and other ID aids efficiently and accurately is a key skill required to confirm the plants you recognise and to name plants new to you.
To help hone these skills, students were invited to play Dr M’s botanical walking game: one-by-one students give Dr M a number, say between 1 and 5.
Dr M then moves off the requisite number of paces and looks down at the plants at his feet and selects one grass and one dicot and waves them in the general direction of the aforementioned student.
The student responds with the name of the family, genus and species, at least as far as they can, and give the reasons for the identification. Other students can then add to the discussion and this way the whole group can check their plant ID and learn more.
The class then returned to the lab to sort the plants collected and to attempt ID using keys.
Favourite keys in the group are the veg key and the keys in the books by Rose and by Streeter.
The Book of Stace is still rarely a first or even second choice for students, Dr M needs to change this culture, but slowly, slowly catchy botanical monkey!
The main focus in keying was Poaceae – with the odd Cyperaceae, e.g. Carex spicata (Spiked Sedge) and a few dicots, e.g. Lathyrus nissolia (Grass Vetchling, possibly a first record for campus), for good botanical measure.
The veg key exercise:
Students had collected very fine flowering specimens of grasses but found that the veg key did not always work to give them the right answer.
This is not surprising really, since the veg key is designed to be used with vegetative material (the hint’s in the name, veg key!).
So flowering material, however beautiful, may not present the right characters, e.g. ligules and auricles on flowering culms can be very different to those on vegetative tillers. Equally, from a flowering culm you cannot tell if the youngest leaf is rolled or folded, or if the sheath is open (overlapping) or closed (fused). You need vegetative tillers for this.
The lesson learned: If you plan to use the veg key, then make sure you collect vegetative material, and if you have flowering material then check your ID in the other keys such as the Book of Stace.
Dr M adds: In any case, it is always important to double check your ID of a new plant in different keys and to read and check the illustrations and descriptions in the books carefully.
How did we do? Overall we found over 65 different vascular plants including eighteen different grass species and all in just a couple of hours in total.
Here’s the list of grasses plus some ID tips:
Agrostis stolonifera (Creeping Bent) – All Agrostis have flat leaf blade tapering to a fine point. (Tribe Aveneae).
Alopecurus pratensis (Meadow Foxtail) – inflated sheath and cylindrical spike-like inflorescence, soft to the touch, lemmas with dorsal, geniculate (=bent) awns (Tribe Aveneae).
Anisantha sterilis (Barren Brome) – Annual, lower leaf sheaths usually showing the Bromus “V”, inflorescence is a branched panicle with spikelets many-flowered and drooping, lemmas with long terminal awns (Tribe Bromeae)
Anthoxanthum odoratum (Sweet Vernal-grass) – sweet smelling when uprooted, hairy ligule (sometimes with auricles), inflorescence oval and spike-like. (Tribe Aveneae).
Arrhenatherum elatius (False Oat-grass) – Orange roots and swollen at the base of the plant, spikelets with dorsal geniculate awns, often tall growing grass in hedge banks and irregularly mown grassland. (Tribe Aveneae).
Bromus hordeaceus (Soft-brome) – lower leaf sheaths usually showing the Bromus “V”, spikelets ovate with numerous florets, lemmas with terminal awns. (Tribe Bromeae).
Cynosurus cristatus (Crested Dog’s-tail) – One-sided, spike-like inflorescence with rather complex sterile and fertile spikelets (check with hand lens). (Tribe Poeae).
Dactylis glomerata (Cock’s-foot) – Inflorescence a branched panicle with clusters of spikelets giving an overall knobbly appearance, sheaths flattened, leaf blade keeled, with tramlines and boat-shaped tip (hooded), conspicuous whitish ligule. One of the easiest grasses to recognise. (Tribe Poeae).
Deschampsia cespitosa (Tufted Hair-grass) – Tufted grass with stiff leaves, with strongly ribbed blades very harsh and rough to the touch, long ligule and fine, silvery spikelets in a large, branched panicle. A large, tussock grass of wet places. (Tribe Aveneae).
Elymus repens (Common Couch) – The prominent auricles are a helpful character for this rhizomatous creeping grass, inflorescence is a raceme with the flattened spikelets arranged broad side on (contrasting with Lolium). (Tribe Triticeae).
Festuca rubra (Red Fescue) – Leaf blade narrow and bristle-like, inflorescence a branched panicle, spikelets ovate and lemmas with terminal awns (contrast with Poa). (Tribe Poeae).
Holcus lanatus (Yorkshire-fog) – Softly hairy grass, lower sheaths have purple stripes (striped pyjamas), inflorescence is compact becoming more open, pinkish or purplish colour when fresh. (Tribe Aveneae).
Hordeum secalinum (Meadow Barley) – Auricles present, though often small, inflorescence is a spike-like panicle and the spikelets are complex and arranged in 3’s (triads – usually one fertile and two adjacent sterile), glumes are awn-like and lemmas have long scabrid awns, once seen never forgotten. This is a tufted perennial of old meadows and distinct from more weedy annual relatives such as Hordeum murinum (Wall Barley). (Tribe Triticeae).
Lolium perenne (Perennial Rye-grass) – Leaf blades ribbed, glossy beneath, auricles may (or may not) be conspicuous, lower sheaths wine red, inflorescence a raceme with the flattened spikelets arranged edge-wise (contrast with Elymus). (Tribe Poeae).
Phalaris arundinacea (Reed Canary-grass) – Large robust grass of wet places, leaf blades flat, conspicuous blunt, whitish ligule. Easy to do with the inflorescence but we didnt have it! (Tribe Aveneae).
Phleum pratense (Timothy) – Hairless leaves and sheaths, lower internodes often swollen and bulb-like, inflorescence spike-like and cylindrical, glumes with short scabrid awns, appearing like little devil horns. (Tribe Aveneae).
Poa annua (Annual Meadow-grass) – All Poa species have inflorescence a branched panicle, triangular in outline, and leaves with boat-shaped tip (hooded) and smooth leaf blade with tramlines (double grove down the middle). Annual meadow grass has wrinked leaves and inflorescence with only one lower branch. Spikelets of Poa are ovate and lemmas with scarious papery margins and no awns (contrast with Festuca). Annual Meadow-grass) often grows in disturbed and trampled ground often with Rough Meadow-grass nearby. (Tribe Poeae).
Poa trivialis (Rough Meadow-grass) – Leaves on flowering shoots (culms) have very long ligule (vegetative tillers have short ligules so beware!), inflorescence has more than one lower branch, often 4 or 5 or more. (Tribe Poeae).
More Poaceous information:
For grass ID you can’t beat the BSBI “Grasses of the British Isles” by Tom Cope and Alan Gray.
Contact Dr M to attend one of his grass ID courses.
And finally, Dr M’s infamous Poaceae song is here…
June 10, 2014
