Saturday, April 11, 2015

'Yellow is the new Blue'

That is not a quote from Coco Chanel but a statement from our environment......

I was contacted last week by a reporter to comment on what I knew about "bastard cabbage" and the next day, on the Channel 8 news, a story ran about this plant and the fact that is is apparently displacing our beloved Bluebonnets.  There is no apparently to it, this is happening......

Non-native, invasive species are wreaking havoc on natural areas and native habitats all over the world and Texas is no exception.  Bastard cabbage, Rapistrum rugosum, is a Eurasian annual seen along most highways in abundance right now, often growing in the middle of a stand of Bluebonnets and it is a pretty combination for sure but that beauty belies something sinister:  This plant is extremely aggressive and out-competes our native species, Bluebonnets included.  The co-evolution of leaf chemistry and leaf-eating insects is an important one when considering population control.  If something eats you, your population can be controlled and if nothing eats you, you can pretty much procreate at-will.  Insects co-evolved with plants for many reasons and one of them is the chemicals that are found in plants, in many cases certain insect species cannot live without obtaining certain chemical via ingesting plant material;  the Monarch butterfly is a great example of this relationship.  Our insects did not co-evolve with Rapistrum and this plant is not eaten to the extent that it's population can be naturally controlled so, it quickly becomes one of if not the dominant species on any site that it occupies.  One of the reasons it is so successful, besides the fact that nothing eats it, is that it is Eurasian and it co-evolved with the European honeybee (yes, the one we have here that everyone is so worried about).  Because it co-evolved with Rapistrum it is super-efficient at pollinating this plant and there is a large crop of seeds which increases the number of individual plants which then produce many more seeds.... this is cyclic.  It only gets worse over time.  So, the color yellow will soon be the new spring wildflower instead of our blue Bonnets and the generational tradition of 'Baby in Bluebonnets' photography will be a thing of the past.  This story is being repeated all over with many different non-native species...... the scariest thing to me is KR bluestem, I will have a piece on that grass very soon, it is a true beast.

What can you do?  Be responsible with your plant choices.  Choose native species, those that occur in your region and if you do utilize non-natives make certain that they do not naturalize, that they cannot naturally reproduce on their own....... I am not afraid of a Peony invasion.

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