Yes, that is correct. We have a new, invasive weed; well, it isn’t exactly new. It showed up last summer, but I ignored it, and a couple of weeks ago, Jim and I discovered that it had invaded a large section of a bed containing Coreopsis verticillata “Zagreb.” Let me back up and start at the beginning. Last summer, I noticed a few silky, bright green stalks poking up between the coreopsis. The bed also contained a cluster of spikes of blazing star (Liatris spicata), a pretty summer perennial. I thought the new stalks might be young sprouts of blazing star. I decided they were too difficult to pull up, so I left them and forgot about them. Earlier this summer, I found a few more stalks, some topped with tiny spiky flowers, and I thought, “Aha! Nutgrass, I’ll have to get rid of that,” but I didn’t. Now, nutgrass isn’t a grass; it’s a sedge, and there are 700 to 800 members of the Sedge family (Cyperaceae). On Saturday, Jim discovered that the sedge growing among my coreopsis is called ky...