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Grasses, rushes, sedges

Is anyone able to recommend a good book for identifying grasses, rushes and sedges?
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I generally use Collins’ Wild Flower Guide, which I like but am finding not ideal for these plants; while I also have Stace 4th edition, which is too advanced for the state of my current knowledge - which is basic. I feel that I’m still at a stage where I need to start with images rather than keys.
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Thanks in advance for any suggestions.

Sterry’s coverage isn’t all that broad, but it does have photographs of the commoner species. It was that and Keble-Martin (good line drawings) that I mostly used when I started with grasses. I still haven’t finished - I can’t deal with Festuca and Agrostis, still have some problems with Poa (and Carex), and just put all timothy down as Phleum pratense agg.

There’s a Phillips (Grases, Ferns, Mosses and Lichens), which I never developed much enthusiasm for. (It has an inconvenient form factor. The other problem is that the photographs are effectively unpressed herbarium specimens, and the text is fairly scant, so you don’t get the salient details.)

I now use Stace 3 and Sell & Murrell (vol. 5). There are a number of books available, but I haven’t seen most of them. Sikula (Hamlyn), which I have, has too sparse coverage to be useful. In your case, perhaps the two BSBI handbooks (sedges and grasses) would be appropriate. Someone else may offer an evaluation of these, and of Hubbard, Rose, Fitter & Fitter, and Christiansen.

This is a good time of year to start with grasses. Apart from Poa annua, which can be found flowering or fruiting just about any time, the three common species currently showing flowering culms are Alopecurus pratensis (a chunky spike, most easily confused with Phleum pratense, but flowering much earlier), Anthoxanthum odoratum (a small grass with a more delicate spike) and Bromus hordeaceus (a loose raceme of somewhat flattened chunky spikelets). You might also find Dactylis glomerata (chunky broken inflorescence), which has a less peaked flowering season even if June is the peak. Anisantha sterilis (similar to the Bromus, but with more flattened species.) Aira praecox is rare here, but should be looked for at this time of year.

I’ve recorded 9 grass species so far this year. (Not Bromus hordeaceus, even tho’ I’ve seen it, because I wasn’t recording in the places I’ve seen it so far.) Apart from those mentioned, Aira caryophyllea (diminutive, early flowering, but rare here - I know two sites), Deschampsia cespitosa (not the easiest of grasses to identify vegetatively, but can be done so all year round), Lolium perenne (sessile flattened spikelets, usually flowers rather later), Melica uniflora (old fruits persisting into late winter at a known site), and Phragmites australis (fairly easily identified from habit, habitat and persisting fruits).

I recorded 50 or so grass taxa last year. The grasses I recorded the most (not the commonest as Festuca and Agrostis are also common) are

  • Dactylis glomerata (cocksfoot) - 75 tetrads, 205 monads
  • Arrhenatherum elatius (tall oat grass) - 65 tetrads, 147 monads
  • Holcus lanatus (Yorkshire fog) - 56 tetrads, 123 monads
  • Poa annua (annual meadow grass) - 55 tetrads, 107 monads
  • Anisantha sterilis (barren brome) - 53 tetrads, 140 monads
  • Bromus hordeaceus (soft brome) - 47 tetrads, 102 monads
  • Alopecurus pratensis (meadow foxtail) - 47 tetrads, 110 monads
  • Lolium perenne (perennial rye-grass) - 40 tetrads, 65 monads
  • Anthoxanthum odoratum (sweet vernal grass) - 37 tetrads, 60 monads
  • Poa trivialis (rough meadow grass) - 36 tetrads, 68 monads
  • Deschampsia cespitosa (tufted hair grass) - 30 tetrads, 43 monads
  • Phleum pratense agg. (timothy) - 30 tetrads, 47 monads
  • Elytrigia repens (couch grass) - 29 tetrads, 43 monads
  • Alopecurus geniculatus (marsh foxtail) - 22 tetrads, 30 monads
  • Phalaris arundinacea (reed grass) - 21 tetrads, 28 monads
  • Triticum aestivum (bread wheat) - 18 tetrads, 23 monads
  • Cynosurus cristatus (crested dogstail) - 17 tetrads, 18 monads
  • Hordeum murinum (wall barley) - 17 tetrads, 21 monads
  • Schedonorus arundinaceus (tall fescue) - 16 tetrads, 18 monads
  • Holcus mollis (creeping soft grass) - 15 tetrads, 18 monads
  • Avena sativa (oats) - 12 tetrads, 15 monads
  • Hordeum vulgare var. distichon (2-row barley) - 12 tetrads, 14 monads
  • Avena fatua (wild oats) - 11 tetrads, 15 monads
  • Phragmites australis (reed) - 11 tetrads, 14 monads
  • Glyceria maxima (reed sweet-grass) - 10 tetrads, 13 monads
  • Lolium multiflorum (Italian rye-grass) - 10 tetrads, 11 monads
  • Poa pratensis (smooth meadow grass) - 10 tetrads, 12 monads
  • Melica uniflora (wood melick) - 9 tetrads, 11 monads
  • Vulpia myuros (rat’s tail fescue) - 7 tetrads, 13 monads

To my surprise, I recorded more taxa in 2020 than 2019, in spite of missing some rarer taxa because of lockdown. Cracking Avena, and splitting Hordeum vulgare varieties must have compensated.

You can get your hands on PDFs of 19th-century works. Other than the problems of taxonomic, including nomenclatural, changes, the Parnell doesn’t look bad.

https://www.biodiversitylibrary.org/search?searchTerm=Grasses+of+Britain

I have recently bought Wallace 2021. FSC Grasses: a guide to identification using vegetative characters. As yet I have not used it, but I see it has text, diagrams and photographs.
the key is a couplet key and there is a glossary. But it’s only grasses.
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I have found Rose.F, 1989. Grasses, sedges, rushes and ferns of British Isles and n-w Europe usually gets me the id. Coloured line-drawings, full text and keys. Second hand copies at £25.00

Thank you, both!.
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At the moment, really I am a complete beginner. I know the grasses my father taught me as a boy - but that’s little more than Cock’s-foot, Timothy, Wood Melick and Yorkshire Fog - and the Wall Barley that, as short-trousered primary school boys, we threw at each others’ jumpers hoping they would stick. And I know the four local Luzula species, and the obvious unmistakable Pendulous Sedge, but not much else.
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I find the subject daunting as I don’t even know the naming of parts, or understand how an infloresence develops through its lifespan. Last weekend I saw what I thought might have been a distinctive, dark, dense and nutty-looking Carex but when I got home I realised that what I had seen was probably the equivalent of buds, before the inflorescence extends and opens; it might have been Common Sedge, Carex nigra, but I dared not go with any ID.
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Your list will help me, I think, lavateraguy, as it gives me an idea of what is likely (even if your neck of the woods is rather different from mine). Incidentally, I found the tetrad/monad respective counts revealing in terms of genuine frequency. They give me pause for thought about the utility of hectad maps.

I forgot to mention that I have the Phillips guide, which I find helpful for ferns but less so for the other groups (not that I’m ever likely to identify a moss or liverwort). I also have Keble-Martin, which I really should take another look at.
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I wondered about Price’s ringbound “A Field Guide to Grasses, Sedges and Rushes” (2016) but I feel nervous about the layout and coverage.
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I think the BSBI handbooks might be too advanced for me (although, having said that, I find those on crucifers and umbellifers excellent).
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I like the look of Rose and will see if I can find a copy second-hand at a decent price.
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Thank you again for your kind thoughts.

Take the tetrad and monad counts with a bit of salt; they depend on more factors than just commonness. One major factor is for how many months of the year I can identify them, which is what puts the Dactylis and Arrhenatherium up at the top of the list. And a bit of systematic canal walking would up the count of Glyceria maxima records.

Most of the grasses on that list grow in large populations (of various densities), but Triticum aestivum and Hordeum vulgare occur (outside of crops) as occasional plants by waysides and growing as pavement/gutter weeds. And Schedonorus arundinaceus tends not to occur in quantity.

If you know Holcus lanatus, then look out for Holcus mollis. It can be distinguished from Holcus lanatus by being hairy only at the nodes (hence hairy knee grass as an alternative to wood soft grass). It also differs in being later flowering (on average), more shade tolerant, with consistently green inflorescences (Yorkshire fog can be white, pink, brown or green), and (in woods; in hedgerows it doesn’t differ much in habit from Yorkshire fog) tending to form extensive colonies. Last year I recorded it flowering in July and early August. Holcus lanatus had a strong peak in late May, but that may be an artifact of having recorded it “everywhere” by then, so subsequent sightings didn’t get into the files; I didn’t record phenology in early years, but records peaked in June and slowing dropped until early August.

While attempting (unsuccessfully) to address HB’s request for books on bracket fungi I stumbled on this, with a positive statement about Rose.

https://www.fungi.org.uk/viewtopic.php?f=18&t=52

For sedges I doubt you can beat the BSBI handbook.

BSBI number 1Sedges of the British Isles. A good recomendation. It has intro with diagrams of key parts, a key for plants in fruit and another for non- flowering specimens. there is a page of excellent line drawings of each species with text opposite in well-ordered characters (i.e the same order of characters for each species).
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I think I would suggest to someone wanting to get to grips with these groups to start with just one of the groups. I find I can then make progress with repeated experience of using the key. That way I can begin to see the range of characters that are found within even one species.
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Having said that, there are groups that I have failed with, and given up on at least till I can get to a workshop for some guided hands-on teaching and learning. Taraxacum comes to mind.

Years ago Charles Sinker produced a “lateral key to grasses” that did not use dichotomous keys but “summed” the visible characters - you might be able to find an “older” botanist who has one (I cannot find mine). Do NOT be tempted to buy at £50+ on the internet. It is only a few pages long - the size that can fall on to photocopiers! This key gave you more “chances” if a character was missing or you got it wrong there still was a chance to get it right.

It should be update - as an app?

Mark

Have a look at https://www.field-studies-council.org/shop/publications/grasses-guide/ or, for a bit more detail, https://www.field-studies-council.org/shop/publications/grasses_aidgap/

I’ve made slow progress with sedges. One reason is that they’re less common, so I get less practice (and I tend not to have the right book with me when I see one). Their tendency to marshy habitats also means that you can always get a close look. (After several years I can more or less handle subg. Vignea, but not subg. Carex.[1])

Grasses have some difficult genera, but their ubiquity means that at the right time of year (late April to September) you can go out and find identifiable grasses anywhere - for sedges I have to pick specific sites.

[1] I’ve perhaps made the wrong division of time between recording easier taxa and studying criticalish groups.

I think Poland’s vegetative key has a good treatment of sedges, and it’s a book that is relatively convenient - small size and broad coverage - to carry in the field.

Another issue is that you (or rather I) tend to forget the characters each year so have to remind myself each year

That’s a problem with sedges, because they’re relatively scarce/local. I have the same problem with willowherbs - except that the problem is the short flowering period, so I’m just beginning to make progress, when the season ends, and I end up starting again next year. (I have retained some progress - it’s now the ruderals with clavate stigmas that give me problems.)

Coming back to Holcus and the Wallace 2021 grasses book, I was speaking the the Wallace concerned yesterday and she mentioned she was in woodland at the weekend testing the book with Holcus. She said it worked even though some of the plants were not ‘typical’ so you had to check all characters on the plant, she was also annotating a copy of the book so that it could be improved if there is a second edition produced in the future.

I haven’t even attempted Holcus so far this year. (I mostly ignore grasses in the absence of culms.)

I just suceeded with Wallace with a Poa annua growing in a mainly tarmaced Bristol urban lane. I had the advantage of there being some flowering spikes too, so could check in Rose . I said I’d “do the grasses when I retired”, but apart from some sand dunes species (which I already knew) and a few alpines I have always found something else to tempt me.
I intend to try another. On verra.

Thank you, everyone, for your thoughts and suggestions.
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I’ve decided to select one grass or sedge or rush per trip or walk, and try to identify that. Yesterday I got to Greater Pond-sedge (Carex riparia) by posting an observation on iSpot and waiting for an expert (in this case JoP) to put me right. Today I confidently identified the ubiquitous Meadow Foxtail (Alopecurus pratensis) by myself, by taking multiple photos and using Collins’ Wild Flower Guide and the VisualFlora website https://visual-flora.org.uk/Home.html which I find quite handy generally.
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Other than that, I think I’ll wait till after a trip to the Dales in June before getting further to grips with the subject, and buying any books, as otherwise I’ll be too distracted in Swaledale and Yoredale - I might need to turn a blind eye up there…

Thanks Bluebird, I have also benefitted from this forum in several ways. One plant per trip with different approaches to getting to an id seems a good plan. Enjoy Swaledale and Yoredale and we look forward to your posting from there.