BLACK KNAPWEED

Centaurea x moncktonii

PROHIBITED MATTER – REPORT THIS WEED (02) 6623 3800

Description Grows to 1 m (but sometimes up to 1.8 m). Slender, upright, branched perennial herb that looks like a thistle but without sharp spines on the leaves.

Leaves Leaves at the base of the stem grow in a rosette and are green, oval-shaped or lobed, up to 25 cm long, and are soft and finely hairy to velvety. Leaves along the flower stem are green, about 3cm long, stalkless and alternate along the stem.

Flowers Pink-purple flowers on the tips of stems that are surrounded by rows of scale (bracts) which are brown and look similar to a little pinecone.

Stems Slender, erect stems with defined edges, rough to the touch approximately 0.3–1.2 m tall.

Dispersal Seed and vegetative reproduction from root fragments dispersed by waterways contaminated soil, hay and attached to machinery. Seed is also spread by wind, vehicles, attached to animals and clothing, and grazing animals eating and excreting the seed.

Confused with Weed species Larkdaisy (Centratherum punctatum). Other introduced Knapweeds and Thistles. Also confused with native plant Centratherum riparium.

Control Please do not attempt to treat or dispose of this weed yourself. Call (02) 6623 3800 if you see this plant anywhere in the Far North Coast region.

Broomrapes

Orobanche spp. (except O. cernua var. australiana and O. minor)

PROHIBITED MATTER – REPORT THIS WEED (02) 6623 3800

Regional Eradication Americas

Description Broomrapes are parasitic plants requiring a host plant to survive and are among the world’s worst crop weeds.

Leaves Very few scale-like leaves occur at the base of the stem and are up to 8 mm long.

Flowers Pale blue to violet, trumpet-shaped, and 1–2.2 cm long. Flowers occurs in summer.

Fruit A single-celled capsule containing hundreds of seeds. The capsule dries and shatters in summer.

Stems Up to 30 cm high and densely branched from ground level. Brown or straw-yellow and covered with soft woolly hairs.

Dispersal Seed dispersed by waterways, wind, contaminated fodder, seed, or soil and attached to livestock, vehicles, and clothing.

Confused with Native species Orobanche cernua var. australiana and Orobanche minor

Control Please do not attempt to treat or dispose of this weed yourself. Call (02) 6623 3800 if you see this plant anywhere in the Far North Coast region.