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

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).

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 (2011)
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)

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. (2011)

Additional information:
Additional online information about Lepidium africanum is available from the Hawaiian Ecosystems at Risk project (HEAR).

Information about Lepidium africanum as a weed (worldwide references) may be available from the Global Compendium of Weeds (GCW).

Taxonomic information about Lepidium africanum may be available from the Germplasm Resources Information Network (GRIN).

References:

Australian Biological Resources Study. 2011. Flora of Australia Online. Australian Biological Resources Study, Canberra.

Frohlich, Danielle/Lau, Alex. 2010. New plant records from O‘ahu for 2008. In: Evenhuis, Neal L. and Eldredge, Lucias G., eds. Records of the Hawaii Biological Survey for 2008. Bishop Museum Occasional Papers 107:3-18.

Lorence, David H./Flynn, Tim. 2006. New naturalized plant records for Kaua‘i and Hawai‘i. In: Evenhuis, Neal L. and Eldredge, Lucias G., eds. Records of the Hawaii Biological Survey for 2004-2005. Part 2: Notes. Bishop Museum Occasional Papers 88:1-5.

Oppenheimer, Hank L. 2003. New plant records from Maui and Hawai‘i Counties. In: Evenhuis, Neal L. and Eldredge, Lucius G., eds. Records of the Hawaii Biological Survey for 2001-2002. Part 1: Articles. Bishop Museum Occasional Papers. 73:3-30.

Orchard, Anthony E., ed. 1994. Flora of Australia. Vol. 49, Oceanic islands 1. Australian Government Publishing Service, Canberra.

U. S. Government. 2011. Integrated Taxonomic Information System (ITIS) (on-line resource).

U.S. Dept. Agr., Nat. Res. Cons. Serv. 2011. The PLANTS Database. National Plant Data Center, Baton Rouge, LA 70874-4490 USA.

Wagner, Warren L./Herbst, Derral R. 1995. Contributions to the Flora of Hawai‘i. IV. New Records and name changes. In: Evenhuis, Neal L. and Miller, Scott, E., eds. Records of the Hawaii Biological Survey for 1994. Part 2: Notes. Bishop Museum Occasional Papers. 42:13-27.