meadow hawkweed
Hieracium caespitosum Dumort.

Overview

Appearance

Hieracium caespitosum is a perennial plant in the sunflower family. It grows from 1-3 ft. (0.3-0.9 m) tall and produces a milky sap when crushed.

Foliage

Leaves long and narrow, up to 6 in. (15.2 cm) long, somewhat hairy on both sides, and form a basal rosette. There are also one or two small leaves found on the stem.

Flowers

Flowers are yellow, dandelion-like, and develop in summer to fall. Flowers in bud are rounded and black in tight clusters on top of the stems.

Fruit

25-30 seeds can be found on one fruit and have fine white bristles which aid in wind dispersal. The plant can spread by seed, stolon, and rhizome.

Ecological Threat

Hieracium caespitosum is native to Europe and occurs in fields, roadsides and sparse woodlands. It was first found in the United States in Washington in 1969.

Selected Images

Maps

Invasive Listing Sources

• Alberta Weed Control Act
• Idaho Noxious Weeds
• Invasive Plant Association of Wisconsin
• Invasive Plant Species of West Virginia
• Montana Noxious Weeds
• National Park Service, Mid-Atlantic Exotic Plant Management Team Invasive Plant List
• Nonnative Invasive Species in Southern Forest and Grassland Ecosystems
• Oregon Noxious Weeds
• Pacific Northwest Exotic Pest Plant Council, 1998
• Washington Noxious Weeds
• WeedUS - Database of Plants Invading Natural Areas in the United States
• West Virginia Invasive Species Strategic Plan and Volunteer Guidelines 2014
• West Virginia Native Plant Society, Flora West Virginia Project, and West Virginia Curatorial Database System, September 3, 1999

References