Present on Pacific Islands?  yes

Primarily a threat at high elevations?  no

Risk assessment results:  High risk, score: 10 (Go to the risk assessment)

Common name(s): [more details]

English: African pepperwort, common pepper cress, rubble pepper cress

Habit:  herb

Description:  "Annual or perennial herbs; stems erect, usually 3-7 dm tall, branched in the upper half, the branches usually ascending, glabrous.  Leaves variable; basal leaves usually oblanceolate, toothed, sometimes pinnately lobed, 2-8 cm long; cauline leaves usually linear-oblanceolate 1-4 cm long, toothed to entire, usually sparsely ciliate.  Flowers in elongate racemes, usually 10-18 cm long; sepals 0.7-0.8 mm long, caducous; petals thread-like, shorter than sepals; stamens usually 2.  Silicles ovate to obovate, 2-3 mm long, 1.5-2 mm wide, notch shallow, the margins scarcely exceeding the short style; pedicel ±flattened, adaxial side sparsely puberulent, ±curved.  Seeds ca. 1.5 mm long" (Wagner & Herbst, 1995, p. 17)

"Annual to perennial herb or subshrub, to 75 cm tall, branched in upper part, finely appressed pubescent or glabrous. Stems erect. Leaf lamina narrowly lanceolate-linear to lanceolate or oblanceolate, 1.5-6 cm long, 0.1-0.8 cm broad, attenuate at base, entire to irregularly serrate, acute, sometimes sparsely ciliate; basal leaves ephemeral; stem leaves reduced in size upwards. Inflorescence dense. Sepals ovate, 0.6-0.8 mm long. Petals thread-like, shorter than sepals or absent. Stamens 2. Infructescence racemose, elongate; pedicels 2-3 mm long, finely puberulous. Silicula flattened-ellipsoidal, 2-3 mm long, 1.5-2 mm broad, slightly winged at apex, notched; valves keeled. Seeds ellipsoidal, reddish brown, 1-1.25 mm long"  (Flora of Australia online).

Habitat/ecology:  In Hawai‘i, naturalized as a roadside weed and in waste areas, littoral vegetation, shrubland/grassland/herbland, and dry disturbed sites  (Wagner & Herbst, 1995, p. 17; Oppenheimer, 2003, p. 3; Lorence & Flynn, 2006, p. 16).  In New Zealand, "gardens, railway ballast, waste land, sand dunes, roadsides, especially near the coast"  (Webb et al., 1988; p. 428).

Propagation:  Seed

Native range:  "Native throughout eastern Africa, now a widespread weed of warm temperate to tropical regions" (Flora of Australia online).

Presence:

Pacific
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Australia (Pacific offshore islands) Lord Howe Island	Lord Howe Island	introduced invasive	Orchard, Anthony E., ed. (1994) (p. 19) "Occasional on the Island. Native throughout eastern Africa, now a widespread weed of warm temperate to tropical regions". Voucher cited: A.N. Rodd (NSW)
Australia (Pacific offshore islands) Lord Howe Island	Lord Howe Island	introduced invasive	Australian Biological Resources Study (2013)
State of Hawaii Hawaiian Islands	Hawai‘i (Big) Island	introduced invasive	Wagner, Warren L./Herbst, Derral R. (1995) (p. 17) Vouchers cited: Herbst & Spence 5321 (BISH), Char & Stemmermann 85.019 (BISH), Engilis 34 (BISH), Takeuchi 5790 (BISH)
State of Hawaii Hawaiian Islands	Kaua‘i Island	introduced invasive	Lorence, David H./Flynn, Tim (2006) (p. 16) Voucher cited: K.R. Wood 11135 (BISH, PTBG, US)
State of Hawaii Hawaiian Islands	Maui Island	introduced invasive	Oppenheimer, Hank L. (2003) (p. 8) West Maui. Vouchers cited: Oppenheimer H30124 (BISH, PTBG), Oppenheimer H50125 (BISH, PTBG)
State of Hawaii Hawaiian Islands	O‘ahu Island	introduced invasive	Frohlich, Danielle/Lau, Alex (2010) (p. 6) Voucher cited: K. Kawelo USARMY 91 (BISH)

Pacific Rim
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Australia Australia (continental)	New South Wales	introduced invasive	National Herbarium of New South Wales (2013) Naturalised
Australia Australia (continental)	Australia (continental)	introduced invasive	National Herbarium of New South Wales (2013) South Australia, Tasmania, Victoria, Western Australia Naturalised
Australia Australia (continental)	Northern Territory	introduced invasive	National Herbarium of New South Wales (2013) Naturalised
Australia Australia (continental)	Queensland	introduced invasive	National Herbarium of New South Wales (2013) Naturalised
New Zealand New Zealand	New Zealand (country)	introduced invasive	Webb, C. J./Sykes, W. R./Garnock-Jones, P. J. (1988) (p. 428)

Indian Ocean
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Mauritius Mautitius Islands (Mauritius and Rodrigues)	Mauritius Island	introduced invasive	U.S. Dept. Agr., Agr. Res. Serv. (2013) Naturalized

Also reported from
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
United States (continental except west coast) United States (other states)	United States (other states)	introduced	U.S. Dept. Agr., Nat. Res. Cons. Serv. (2013)

Control:  If you know of control methods for Lepidium africanum, please let us know.