Tuesday, 12 June 2012

An Unusual Plant..

Colin is well-used to  mowing carefully around the various species of orchid we have growing in the lawn, so when he noticed an unfamiliar plant he was quick to stop the mower and call me over.

The plant in question is a Common Broomrape  (Orobanche minor)


The unusual thing about all Broomrapes is that they are parasitic. Lacking chlorophyll to synthesise their own products they take their nutrients from the roots of a host plant.

In this case the host plant is clover, as can be seen from the following photos..



Common Broomrape is easily confused with other Broomrapes, of which there are several. These are usually named after their host plant, such as "Thistle Broomrape" or "Thyme Broomrape". Unlike Thyme Broomrape, Common Broomrape is not scented and grows nearly twice as tall - up to 60cm.

The best identifier, though,  is the host plant. Whilst Common Broomrape can host on a variety of plants, it especially favours clover and wild carrot.

Whilst our little plant is unlikely to do us much harm, there is debate about the amount of damage Broomrapes can cause to crops by taking nutrients from the roots of its host.  In Spain and Romania in particular, research is looking into damage the Broomrape (Orobanche cumana), which hosts on sunflowers, does to the production of sunflower oil.

And I thought it was simply an interesting plant to be saved from the ravages of the lawn mower!
You never know what menaces lurk in your own back yard...

3 comments:

Food, Fun and Life in the Charente said...

New one on me, I had better go out and look around and see what we have!! Diane

Pollygarter said...

We just noticed one in our lawn as well. Funny-looking things, aren't they?

Susan said...

There seem to be a lot of them around this year, and they are in their prime at the moment. I've got a couple of species in the orchard. BTW, it is never safe to base your identification of a broomrape on what you think the host appears to be. They can pop up a considerable distance from the actual host and be surrounded by something completely unconnected. Broomrapes are rarely easy to ID to species level. Individual plants vary a lot in colour and size, and most species have a lookalike that can be difficult to separate. My page on them is here: http://loirenature.blogspot.fr/2009/12/broomrapes-orobanche-spp.html.

Having said all that I think your ID of this one is correct.