Pulicaria paludosa

It is known for its woody, rhizomatous root system, which allows it to resprout from roots even after being pulled, making control difficult. While it is technically a perennial in some life cycles, its ability to spread and act aggressively in some regions means it is often referred to as a weed. It is native to Europe, particularly Spain and Portugal, and it is known as an introduced species in California, Arizona, and Clark County, Nevada, where it grows as a weed on roadsides, wetlands, riparian corridors, and other damp, disturbed areas. It is an annual, biennial, or perennial herb growing a few centimeters tall to well over a meter tall from a rhizomatous root system. The leaves are alternately arranged with blades in a variety of shapes from linear to oblong or oval. The herbage is coated in soft hairs. The inflorescence bears many flower heads. Each head has narrow, pointed, hairy phyllaries, a large dense center of many yellow disc florets, and a short fringe of many rectangular yellow ray florets, which are only about 2 millimeters long each. The fruit is an achene tipped with a pappus of bristles.