Beggarticks Bidens frondosa
IDENTIFICATION — If you, or your pet, have ever brought “stickers” home after walking through a patch of weeds in late summer or early autumn, you’re probably familiar with beggartick seeds. This 12- to 42-in.-tall summer annual has leaves comprised of three to five leaflets that have coarse teeth. In early summer they have 1-in. golden-yellow flowers, that look like miniature black-eyed Susans. The ½-in. seeds are where this plant gets its name. These wedge-shaped seeds have two prongs that are covered with tiny barbs that grab clothing or animal fur. They hitchhike to new locations this way.
FAVORITE CONDITIONS — Found throughout North America, beggarticks prefer full sun and moist soil. But they’re not picky – they’ll tolerate almost any conditions where the seeds come to rest. Beggarticks are commonly found in roadside ditches and other neglected waste areas. Due to their hitchhiking behavior, you’re just as likely to find them in your perennial border or vegetable garden, although rarely in your lawn.
CONTROL — As with most annual weeds, try to keep beggartick from going to seed. In late spring, hoe out seedlings as they sprout. The shallow taproots make them easy to get out of the ground, so you can hand pull mature plants, too. If you have a well-established patch of beggarticks, most broadleaf herbicides will kill them. Carefully spray while the weeds are actively growing. Both selective herbicides, like Trimec, and nonselective ones, like Roundup®, will work. Follow the label instructions so you don’t harm surrounding plants.