Bighead Knapweed
Centaurea macrocephala

Family: Sunflower (Asteraceae)
AKA: Giant Knapweed, Globe Centaurea, Lemon Fluff,
 Yellow Bachelor's Button,  Armenian  Basketflower,
 Yellow Hardhat
Photo taken on: July 31, 2023
Location: Almont, CO
Life Zones: Plains to foothills
Habitat: Meadows, grassy clearings

Grows 3 to 5 feet tall with large, bright green, oval-shaped leaves. It has bright yellow, thistle-like flowers, 3-4" across, enclosed in glossy, light brown bracts growing singly at the top of strong, stiff stems. It is a garden escapee.

Flora of North America reference.

Photo Credit: Mary Nell Beatty