Identifying grasses

Lolium multiflorum CC image by Matt Lavin

I think a good place to begin is the Field Studies Council's fold-out guide (a bargain at £3 or we have some you can borrow). The pictures are small but clear, and the reverse features an excellent lateral key which will get you looking at important features like ligules, glumes and awns. The guide has 30 common species so it won't have things you might find in unusual habitats.

I went on a little botany class at my local nature reserve and the tutor was using Dominic Price's Field Guide to Grasses, Sedges and Rushes. I've found this really useful this year and recommend it heartily. It's full of good photographs, and being a little booklet is really useful in the field. There are a couple you can look at in the field centre.

Rose's 'Grasses, Sedges, Rushes and Ferns of the British Isles and north-western Europe' has much more detailed drawings. It's big and quite expensive and not very convenient for lugging round the countryside - more the sort of thing to consult back in the lab. It's got a dichotomous key to the species (you will remember that showing you can use one is part of your assessment). There are detailed drawings and I like the simplicity of the descriptions: you can see what the distinguishing characteristics are quite easily. This is my favourite one to look at in the lab. Likewise, you can consult our copies.

Some people prefer Fitter, Fitter and Fitter which is shorthand for their Collins Pocket Guide to Grasses, Sedges, Rushes and Ferns of Britain and Northern Europe. This is more pocket-sized and has very clear diagrams. The key is different - it's a 'single access key' a bit like the one on the back of the FSC fold-out guide. It's rather helpful to have two different approaches like this, when you're starting out on something new (it increases your chance of getting to the right answer!) Sadly it seems to be out of print and second-hand copies sometimes quite expensive. But you can borrow ours if you can't find one.

 I've recently discovered this online key from the Field Studies Council. You tick off the features your grass has and it points you at the most likely family, and then suggests species. I think it might be most helpful for someone who's already picked up some of the terminology, as there aren't any supporting diagrams or photos until you get to the end.


A classic book for grasses is "Hubbard" - a Penguin paperback first published in the 1950s. I'm not so keen because I find it confusingly detailed, but some people love it and it has very comprehensive diagrams of the glumes and lemmas etc. I do like the lists in the front which suggest species for different habitats. It's got a dichotomous key too. You can pick one up very cheaply.

If you want to feel like a Proper Botanist then "Stace" - and his 'New flora of the British Isles' is absolutely the industry standard for vascular plants, so I feel obliged to mention it. But it can be a bit daunting - no illustrations and everything's in there, including all the rarities. Maybe not a good place to start. But you can come and look at our copy, or there's one in the library.

Recently I bought Cope and Gray's 'Grasses of the British Isles'  - it's a new handbook from the BSBI and its layout reflects new thinking about grass taxonomy. I'm sure some grass fans will like it but I'm not massively keen, and I don't like the key. But it's here if you want to have a look.


The usual advice about collecting applies (though realistically no-one is going to do anything but give you a funny look if they see you cramming grass into a carrier bag at the side of a road - I speak from experience). Take the specimen from down at the base (don't dig up the roots, they're not usually important to identification anyway). Make sure you make a note of the form of the plant - is it in a definite clump? This can be a useful characteristic to know.

You want to remember where you found your specimens and be able to cross-refer to the right part of your notepad,  so you might find it helpful to make or buy 'jewellery tags' like in my picture below (modelled by a winter twig).

When you arrive home you can store them in the fridge for a while without too much wiltage. But you really want to get them identified while they're fresh, when important features like ligules are at their best. Then (also before they've wilted) you want to put them in your botanical press.

I've also written about how to mount your grass specimens for display. You should check you are using up-to-date names with the Natural History Museum's database (more can be found on the 'what' page).

Dave M. is an accomplished agrostologist on the quiet, so if you do have any questions, do come and see us.