Monday, August 13, 2012

The Biggest, Baddest Bull Thistle






Species name: Cirsium vulgare

Common name: Bull thistle

Location: Ontario

This plant, often deemed a "weed," is native to Europe and parts of northwestern Asia but has been naturalized throughout most of North America. It prefers to grow in recently disturbed areas (where many non-native asters thrive), and so often pops up in gardens or lawns if they have recently been re-landscaped. That's the virtue of the beast! Because of its preference for disturbed areas, it can become invasive in prairie-like habitats which are, by definition, constantly being disturbed (hopefully; a healthy prairie has wildfires that blaze through once every 7 to 10 years).

Bull thistles are clearly not for the faint at heart for weeding, especially when they get to be this size. They can cause some serious damage to anyone (or any animal) that accidentally brushes up against it, is pushed against it, or falls on it. I wouldn't go as far as saying there's a serious threat of being impaled by a bull thistle, but it's certainly not a plant I would want a close encounter with!

Like many members of its family, the Asteraceae, the bull thistle is actually 100% edible when  young (as in, before flowering) with the taproot being the tastiest. It can be boiled then eaten exactly like a carrot or boiled further and mashed like potatoes. There aren't many people that would mess with this plant long enough to figure out you could eat it, so hats off to whoever discovered this fact! That's one brave soul.

I figured this would be a good time to point out that quite a few of my pictures, seemingly mostly the pictures of the aster (or sunflower) family, have bees in them with giant yellow sacs on their back legs. Those aren't actually sacs, those are giant balls of pollen. Most people think that bees are excellent pollinators, and that lots of bees in your garden means that you have lots of cross-pollination that's occurring. In reality, bees are absolutely terrible pollinators, and the globs on their back legs shows you precisely why. Bees hate having pollen attached to any part of their body, which is completely understandable; would you like sand crusted all over your skin? Probably not too comfortable. So bees have actually perfected the art of grooming while in flight. They use their antennae and front legs to meticulously groom all of the pollen off of their legs, back, head and torso. This doesn't mean pollen is useless to a bee; it's actually incredibly useful. They pack it onto their legs to carry back to their hive, and store it as food. On a lucrative pollen day, a bee will only return to the hive when the back legs get so encrusted with pollen that it's difficult to fly.

So now you know!

As a non-blog side note: sincerest congratulations goes out to my lab-mate Jessie who just successfully defended her Master's degree! Proud of you!