Lepidium bonariense L., Brassicaceae

Click on an image for links to BIGGER PICTURES

Present on Pacific Islands?  yes

Primarily a threat at high elevations?  no

Common name(s): [more details]

English: Argentine cress, Argentine pepperweed, Argentine pepperwort, peppercress

Habit:  herb

Description:  "Annual or biennial. Stem erect, branched above, hairy, (10)-20-45-(90) cm tall. Leaves hairy. Basal and lower stem leaves falling at flowering, 2-3-pinnatisect with linear segments, (2)-3-10 x 1-4 cm; petiole expanded at base, < lamina. Upper stem leaves becoming sessile, pinnatifid, 1-3 x 0.5-1.5 cm. Racemes 5-15-(30) cm long; rachis hairy; pedicels hairy, spreading, 2.5-4 mm long at fruiting. Sepals with long tangled hairs or glabrous, 0.5-1 x 0.3-0.5 mm. Petals white, linear, much < sepals or 0. Stamens 2. Silicle circular or broadly elliptic, 2.5-3.5 x 2.5-3.5 mm; style free from the narrow wing, c. 0.1 mm long, not protruding beyond the apical notch; valves glabrous with fine veins when ripe. Seeds brown, ovoid, winged, c. 1.5 mm long"  (Webb et al., 1988; p. 429).

Description from Flora of Australia online.

Habitat/ecology:  In New Zealand, "waste land, railway ballast, roadsides"  (Webb et al., 1988; p. 429).  An occasional weed of disturbed soil, wasteland and roadsides on Norfolk and Lord Howe Islands (Flora of Australia).

Propagation:  Seed

Native range:  Northern Argentina, Brazil (Rio Grande do Sul, Santa Catarina) Paraguay, Uruguay (GRIN).

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)
Australia (Pacific offshore islands) Norfolk Islands	Norfolk Island	introduced invasive	Orchard, Anthony E., ed. (1994)
Chile (offshore islands) Juan Fernández Islands	Isla Más a Tierra (Robinson Crusoe Island)	introduced invasive	Atkinson, Rachel/Sawyer, John (2011)
Chile (offshore islands) Juan Fernández Islands	Isla Más a Tierra (Robinson Crusoe Island)	introduced invasive	Danton, Philippe/Perrier, Christophe/Martinez Reyes, Guido (2006) (pp. 461, 465, 555)
Chile (offshore islands) Juan Fernández Islands	Isla Más Afuera (Alejandro Selkirk Island)	introduced invasive	Atkinson, Rachel/Sawyer, John (2011)
Chile (offshore islands) Juan Fernández Islands	Isla Más Afuera (Alejandro Selkirk Island)	introduced invasive	Danton, Philippe/Perrier, Christophe/Martinez Reyes, Guido (2006) (pp. 461, 465, 555) Voucher cited: Danton G(1427)1192
State of Hawaii Hawaiian Islands	Hawai‘i (Big) Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 407) Voucher cited: Herbst 5336 (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 (2011) Not common
Australia Australia (continental)	Queensland	introduced invasive	National Herbarium of New South Wales (2011)
Japan Japan	Japan (country)	introduced	Mito, Toshikazu/Uesugi, Tetsuro (2004) (p. 183)
New Zealand New Zealand	New Zealand (country)	introduced invasive	Webb, C. J./Sykes, W. R./Garnock-Jones, P. J. (1988) (p. 429)

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) Georgia, South Carolina

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

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

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

References:

Atkinson, Rachel/Sawyer, John. 2011. Naturalized species in the Juan Fernández Archipelago, Chile. Unpublished spreadsheet.

Danton, Philippe/Perrier, Christophe/Martinez Reyes, Guido. 2006. Nouveau catalogue de la flore vaculaire de l'archipel Juan Fernández (Chile) [Nuevo catálogo de la flora vacular del Archipélago Juan Fernández (Chile)]. Acta Bot. Gallica 153(4):399-587.

Mito, Toshikazu/Uesugi, Tetsuro. 2004. Invasive alien species in Japan: the status quo and the new regulation for prevention of their adverse effects. Global Environmental Research 8(2)/2004: 171-191.

National Herbarium of New South Wales. 2011. PlantNet: New South Wales Flora online. The Plant Information Network System of the Botanic Gardens Trust Version 2.0. Online resource.

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

U.S. Dept. Agr., Agr. Res. Serv. 2011. National Genetic Resources Program. Germplasm Resources Information Network (GRIN). Online searchable database.

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./Sohmer, S. H. 1999. Manual of the flowering plants of Hawaii. Revised edition. Bernice P. Bishop Museum special publication. University of Hawai‘i Press/Bishop Museum Press, Honolulu. 1919 pp. (two volumes).

Webb, C. J./Sykes, W. R./Garnock-Jones, P. J. 1988. Flora of New Zealand, Volume IV: Naturalised pteridophytes, gymnosperms, dicotyledons. Botany Division, DSIR, Christchurch. 1365 pp.