If you’ve ever engaged in mortal combat with a patch of ragweed, dandelion, or crabgrass in your garden, you might understand the twin emotions of rage and begrudging admiration when it comes to weeds: They. Just. Won’t. Die. When it comes to commercial agriculture, weeds pose a more existential threat—globally, the proportion of our harvest that is lost to weed infiltration is enough to feed millions, and, even with advanced herbicides, weeds cost farmers in North America an estimated $33 billion in lost yield each year. No matter what we throw at them, weeds just seem to get stronger. This episode, we follow a group of scientists along on a 149-year-old quest to see just how long weeds can survive—and, along the way, figure out what we can learn from weeds, what we really ought to thank them for, and what is a weed, anyhow? Listen in now for zombie seeds, a midnight treasure hunt, and the wild ways that weeds have outwitted us for millennia.