''Raoulia eximia'' is a species of plant in the family

Asteraceae Asteraceae () is a large family (biology), family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the Order (biology), order Asterales. The number of species in Asteraceae is rivaled only by the Orchi ...

. It was first formally described in 1864 by

Joseph Dalton Hooker Sir Joseph Dalton Hooker (30 June 1817 – 10 December 1911) was a British botanist and explorer in the 19th century. He was a founder of geographical botany and Charles Darwin's closest friend. For 20 years he served as director of the Ro ...

. It is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to New Zealand. The plant is commonly known by its

Māori Māori or Maori can refer to: Relating to the Māori people * Māori people of New Zealand, or members of that group * Māori language, the language of the Māori people of New Zealand * Māori culture * Cook Islanders, the Māori people of the Co ...

name tutāhuna and as the true vegetable sheep, suggesting its appearance at a distance resembling a sheep.

Description

On the vegetable sheep only the buds, that never unfold, can be seen externally because their stems are so branched, and have small woolly leaves that are disposed on the extremity of the twigs in a closely tight way. The dense, hard and convex shape of ''Raoulia eximia'' formed by its compressed structures, according to Cockayne it makes "an excellent and appropriate seat for a wearied botanist". The species of ''

Raoulia ''Raoulia'' is a genus of New Zealand plants in the tribe Gnaphalieae within the family Asteraceae. Many ''Raoulia'' species grow in alpine areas, forming very fine and dense growths. These compact growths form large amorphous cushion-like mas ...

'' can be easily mystified because of the overall resemblance in general appearance, despite being taxonomically distinct. ''Raoulia eximia'', the Canterbury vegetable sheep, usually found on rock outcrops has grey to grey-green colouration and narrow buds.

Hook.f. Sir Joseph Dalton Hooker (30 June 1817 – 10 December 1911) was a British botanist and explorer in the 19th century. He was a founder of geographical botany and Charles Darwin's closest friend. For 20 years he served as director of the Ro ...

describe the species as a rigid plant that form large woolly balls on the mountains covered in soft, velvety, white tomentum. "Leaves most densely compacted, wholly hidden amongst woolly hairs, imbricated all round in many series, 1/8 in. long, membranous, broadly linear- or obovate-oblong, rounded at the tip, bearing at the back above the middle a dense thick pencil of white velvety hairs, these bundles of hairs, meeting beyond the leaves, envelope the whole". The plant has circular cushions up to 1 m. or more diam., up to 5 dm. or more tall formed by the woody branches very close-packed and a strong stock. "Florets 10–15 or more. Achenes hardly 1 mm. long, clad in long silky hairs; pappus-hairs rigid"

Distribution

About 93 percent of the alpine plants are just found at New Zealand Biological Region. New Zealand has only a few alpine genera among all the genera of alpines and they are usually the less notable members, except for ''Raoulia''. The light-coloured cushions of the true vegetable sheep can be found on the drier

fellfield A fellfield or fell field comprises the environment of a slope, usually alpine or tundra, where the dynamics of frost (freeze and thaw cycles) and of wind give rise to characteristic plant forms in scree interstices. Soil dynamics The freeze-tha ...

s located on the east of the

Southern Alps The Southern Alps (; officially Southern Alps / Kā Tiritiri o te Moana) are a mountain range extending along much of the length of New Zealand, New Zealand's South Island, reaching its greatest elevations near the range's western side. The n ...

, between north

Otago Otago (, ; ) is a regions of New Zealand, region of New Zealand located in the southern half of the South Island and administered by the Otago Regional Council. It has an area of approximately , making it the country's second largest local go ...

and southern Nelson Marlborough, from mid-Canterbury to north

and in the S. Subalpine to alpine rocky ground and fellfield from lat. 41 to 45 30'.Research. Raoulia eximia distribution.
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Habitat preference

The formation of soils on the mountains is high because of the wind-blown material, but the constant strong winds, cold summers and frequent freeze-thaw cycles draw off all the soil formed. The plants in the alpine zone, like ''R. eximia'', are exposed to high moisture in the soil, except when the ground is frozen. However, excess water, which increases with rainfall, makes the soil more acidic and also provokes the leaching of nutrients. ''R. eximia'' can be found in raw soils, with low nutrient concentrations, typically mean total phosphorus (P) 69.5 mg·kg-1, and total nitrogen (N) 0.04%.

References

{{Taxonbar, from=Q15599177 Endemic flora of New Zealand Gnaphalieae Plants described in 1864