Saturday, 18 June 2011
This week's Illustration Friday prompt is launch. This flower and seed belong to a plant called Stork's Bill or Filaree (Erodium cicutarium), which is native to the Mediterranean, I believe. Here in North America it's considered a weed, and in some places an invasive one. Once you've got it in growing conditions it likes, it can be hard to keep it from spreading.
That's because it has a sneaky way of planting its own seeds.
The coiled awn you see on the seed acts like a spring, and when the seed is ripe it can be launched up to a half-metre away from the parent plant. But that's not the end of things. Humidity acts on the awn, causing it to coil and uncoil, which in turn causes the seed to drill itself into the ground.
Self-planting. Pretty darned cool.
For a pretty darned cool time-lapse photo of the awl's coiling action, scroll down a bit on this page. And for anyone in Canada who hasn't ever listened to Quirks and Quarks, the radio show the report on the page was taken from... Seriously? You've missed some good popular science then, folks.