Friday, 10 June 2016

Wildflower of the Month: Buttercups

Meadow buttercup: flower stalk is not at all groovy.
Probably indulges in "dad dancing" when
nobody is looking!
Image courtesy of Floral Images
http://www.floralimages.co.uk/page.php?
taxon=ranunculus_acris,1  
Lots of Buttercups in bloom right now - they are our Wildflower of the Month and I'll be talking about them this afternoon to the #OutFortheWeekend team on BBC Radio Scotland.

But why Buttercups? They are not beautifully scented like the Sweet Violet, threatened by an alien invader like the English Bluebell or essential for the survival of rare invertebrates, like Bird's-foot Trefoil. You can't eat them, use them to starch ruffs (!) or make a herbal remedy out of them - they are poisonous. So, to be brutal - what use are they to humans apart from looking pretty?

Well, knowing which Buttercup you are looking at can tell you a lot about the site where it grows - how wet or well-drained a garden is, how a meadow may have been managed centuries ago. So if you are a keen gardener and buying a new house, checking the identity of the Buttercups in the garden will give you a good idea about your soil and might even save you money!

Bulbous Buttercup: flower stalk is
groovy; sepals point downwards.
Image courtesy of Floral Images
http://www.floralimages.co.uk/page.php?
taxon=ranunculus_bulbosus,1
There are three common Buttercups you are likely to see growing wild in lawns and meadows. Creeping Buttercup and Meadow Buttercup both grow right across Britain and most of Ireland, whereas Bulbous Buttercup becomes less common in the north and west of both countries. Click on the names to see BSBI distribution maps for each plant.

Bulbous Buttercup likes old meadows, preferably ones that have never been ploughed, and good drainage - got to make sure that bulb doesn't go rotten over winter!

Meadow Buttercup is a bit less picky (no bulb to worry about) but still likes fairly well-drained soil and, like Bulbous Buttercup, is often found alongside other much-loved wildflowers on nature reserves.

Creeping Buttercup is a different matter: it can cope with much wetter conditions than the other two but is also a rampant invader of bare, dry soil. You'll find it growing between the cigarette butts and sweetie wrappers on bits of bare ground near bus stops as well as in damp rushy meadows.

A garden full of Creeping Buttercup signals either heavy claggy soil and lots of hard work ahead for a gardener, or recent digging which has allowed a bothersome weed to take hold, i.e. lots of hard work ahead for a gardener. A garden with a Creeping Buttercup patch 6 feet long and 2 feet wide would make me wonder why the owners dug it up and what on earth they had buried under there!

Creeping Buttercup: flower stalk is groovy;
sepals point upwards
Image: https://commons.wikimedia.org/wiki/File:
Ranunculus_repens_flower4_ST_(15888487920).jpg
The easy bit is how to tell them all apart - just 2 steps:

Step 1: is the flower stalk groovy? If it doesn't have a long groove running down the stalk, it's probably Meadow Buttercup. If it does...

Step 2: are the sepals pointing up or down? [If you're not sure what a sepal is, think of a rosebud - it's surrounded by green bits that fold downwards once the bud has unfurled - those green bits are the sepals.] Buttercup sepals are yellow like the petals. If they are pointing down: Bulbous Buttercup. Pointing up: Creeping Buttercup.

So now you know your Buttercups, you can stand in a meadow or garden and hold forth with some confidence on whether it was ploughed in the 1900s or how much work the gardener has to do. And you can ask an estate agent to lower the asking price of a house because you've spotted that patch of Creeping Buttercup!

All three Buttercups are in flower now so watch out for them this month and share your photos - please tweet to @BSBIbotany using the hashtags #WildfloweroftheMonth and #outfortheweekend If you missed the interview with Fiona Stalker on 'Out for the Weekend' then you can catch it again here, starting at 01.42.00.