Wednesday, July 20, 2011

What a fiasco!

Yellow crucifers give me hives; not literally but mentally. It's lucky I have someone to identify them for me, then point me in exactly the right direction to find them. Well, that's meant to be my foolproof plan.

My local plant identification consultant informed me (in person and via most annoying text messages) that bastard cabbage (Rapistrum rugosum) was growing on a roadside near Beeston. I get directions. I go to find it. I fail.

I check location again with consultant. Go to site again. Miss it again. Meh.

Today, finally, finally, on this miserable grey July day, I found my quarry.

How did I miss it? 5 feet tall and drooping over the road?
The yellow flowers are singularly unhelpful in identifying this plant (or any yellow crucifer in fact).

You need to look at the fruits, which in this case are striking; flask-shaped, globular and ribbed.

The fruit is shaped like a mini Chianti bottle. A traditional straw-enclosed Chianti bottle is called a fiasco.
A fiasco (Picture from Wikipedia here)
The Beeston plant is most probably Rapistrum rugosum ssp linnaeanum. Bastard cabbage was introduced to the UK from the Mediterranean in 1739, is increasing its range and can be invasive. It is also found in bird seed mixes.

If I was an insect, I might have found this plant a wee bit faster. The cabbage family, despite having what we see as rather insignificant white or yellow flowers, are actually using sophisticated UV nectar or pollen guides on their petals to attract pollinators (Horovitz and Cohen, 1972, Sasaki and Takahashi, 2002). There are some photos of black mustard (Brassica nigra) flowers under UV light here.

[I've edited this post to add the photo below and some text about harlequin ladybirds].

There were a number of the unwelcome alien harlequin ladybirds (Harmonia axyridis) on the vegetation down the lane, including this one on the bastard cabbage.

Harlequins come in a number of colour variations. I believe this is Harmonia axyridis succinea

Another plant with much bigger Chianti bottle fruits is yellow water lily (Nuphar lutea). This one was out on the lake at Witley Court in Worcestershire. 


Further information
Horovitz A and Cohen Y (1972) Ultraviolet reflectance characteristics in flowers of CrucifersAmerican Journal of Botany. volume 59, Issues 7, Pages 706-13. Only first page available here
Sasaki K and Takahashi T (2002) A flavonoid from Brassica rapa flower as the UV-absorbing nectar guide. Phytochemistry. Volume 61, Issue 3, Pages 339-343. Abstract available here.

2 comments:

  1. You stick to small plants and I will look after the big ones!

    Ballota nigra

    ReplyDelete