Actually Brandon, that's Tansy Ragwort, typically a biennial or sometimes a short lived perennial.....but easily confused with Common Tansy, a rhizomatous perennial. Even so, from my experience, the effectiveness of mechanical control on Tansy Ragwort is minimal, but any reduction in seeds is a good thing.
And yes PolarBear, Tansy Ragwort is toxic (chronic exposure), with horses being the most prone to poisoning.