REPORT

Invasive Plant Details

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Brown Knapweed

Latin Name: Centaurea jacea

Priority Ranking: High Priority

Identification

Flower: Pink to purple, thistle-like flower heads that bloom from mid to late summer.

Leaves: Lance-shaped, green, slightly hairy leaves, with basal leaves being larger and more lobed.

Stems: Erect, slightly hairy, and branched, growing up to 1 meter tall.

Growing Environment: Found in meadows, grasslands, pastures, and along roadsides.

Growth Habit: A perennial herb that grows up to 1 meter tall. It forms loose clumps that can spread over time through seed dispersal and vegetative growth and create large monocultures. In situ, it often appears in scattered patches, particularly in open meadows or disturbed areas, where its bright purple flowers are conspicuous.

Priority Ranking: High Priority

Impacts on Environment

Impacts: Invasive in some regions, particularly in grasslands and pastures where it can crowd out native species.

Toxicity: This plant is toxic to horses when consumed.