Lepidium oleraceum

Lepidium oleraceum

Nationally Vulnerable (NZ TCS)
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Brassicales
Family: Brassicaceae
Genus: Lepidium
Species:
L. oleraceum
Binomial name
Lepidium oleraceum
Synonyms

Lepidium oleraceum is a herb in the family Brassicaceae, endemic to New Zealand. Its English common name is Cook's scurvy grass;[1] Māori names include nau, ngau, naunau and heketara.[2][3]

Its specific epithet oleraceum means "vegetable/herbal" in Latin and is a form of holeraceus (oleraceus).[4][5]

Taxonomy

There are three recognised varieties:[6]

  • var. frondosum Kirk
  • var. acutidentatum Kirk
  • var. serrulatum Thell.

Distribution

In New Zealand it is native to coastal areas of the North and South Islands, Stewart Island, the Three Kings Islands, the Snares Islands, the Chatham Islands, the Auckland Islands, the Antipodes Islands and the Bounty Islands.[6][7] Although this species was once widespread, it is now mostly restricted to off-shore rock stacks and islets, such as Mana Island.[8]

Conservation status

The small populations are highly threatened, one of the reasons being reduced populations of seabirds which they are dependent on to provide highly fertile and disturbed soils associated with nesting grounds. Additionally the species is susceptible to browsing by livestock, rodents, snails, and insect herbivores such as aphids, leaf miners, the diamondback moth (Plutella xylostella), and the small cabbage white butterfly (Pieris rapae).[9] It is also affected by white rust, a fungus-like disease caused by the oomycete Albugo candida.[8][9]

Connection with James Cook

During his voyages of exploration James Cook collected a number of plant species at various locations which were used to help ward off scurvy amongst his crew. While visiting Tolaga Bay in New Zealand on his first voyage, Cook noted in his journal on 27 October 1769: "the other place I landed at was the north point of the Bay where I got as much Sellery and Scurvy grass as loaded the Boat".[10] Historian John Cawte Beaglehole believed that "scurvy grass" in this case referred to Lepidium oleraceum.[10] Specimens of the plant were collected by botanists Johann and Georg Forster on Cook's second voyage. [11]

Uses

Young leaves may be eaten raw or cooked. They have a hot cress-like taste and are a rich source of vitamin C.[12]

References

  1. ^ Lehnebach, Carlos A.; Meudt, Heidi (1 October 2022). Native Plants of Aotearoa. Te Papa Te Taiao Nature Series. Te Papa Press. p. 31. ISBN 978-1-9911509-3-6.
  2. ^ "New Zealand Flora". Retrieved 28 April 2008.
  3. ^ "Lepidium oleraceum. Nau. Cook's scurvy grass". Landcare research. Retrieved 2 April 2012.
  4. ^ Parker, Peter (2018). A Little Book of Latin for Gardeners. Little Brown Book Group. p. 328. ISBN 978-1-4087-0615-2. oleraceus, holeraceus = relating to vegetables or kitchen garden
  5. ^ Whitney, William Dwight (1899). The Century Dictionary and Cyclopedia. Century Co. p. 2856. L. holeraceus, prop. oleraceus, herb-like, holus, prop. olus (oler-), herbs, vegetables
  6. ^ a b "Flora of New Zealand: Taxa". Retrieved 28 April 2008.
  7. ^ "Amey et al.—Lepidium oleraceum on Bounty Islands". Archived from the original on 6 July 2008. Retrieved 28 April 2007.
  8. ^ a b "Conservation genetics of threatened plants". Landcare Research. Archived from the original on 17 May 2010. Retrieved 29 April 2008.
  9. ^ a b Hasenbank, M.; Brandon, M.; Hartley, S. (2011). "White butterfly (Pieris rapae) and the white rust Albugo candida on Cook's scurvy grass (Lepidium oleraceum)". New Zealand Journal of Ecology. 35: 69–75. Retrieved 7 June 2016.
  10. ^ a b Lange, P.J.; D.A. Norton (1996). "To what New Zealand plant does the vernacular 'scurvy grass' refer?" (PDF). New Zealand Journal of Botany. 34 (3): 417–420. doi:10.1080/0028825x.1996.10410705. Archived from the original (PDF) on 30 August 2008. Retrieved 29 April 2008.
  11. ^ "Lepidium oleraceum". Type collection of Lomonosov Moscow State University (MW). Retrieved 29 April 2008.
  12. ^ "Lepidium oleraceum – Plants for a Future database report". Retrieved 28 April 2008.