''Coriaria arborea'' is a highly poisonous and common native shrub or small tree of New Zealand. The common name for the plant is tree tutu'', and it is one of the New Zealand species of ''Coriaria'' known by the name tutu. ''Coriaria arborea'' is found in scrub and open areas from the coast to the hills across the country. A straggling plant, it can grow to high. The leaves grow opposite on slender stems while flowers are arranged in drooping

raceme A raceme () or racemoid is an unbranched, indeterminate growth, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are ...

s. ''C. arborea'' is capable of

nitrogen fixation Nitrogen fixation is a chemical process by which molecular dinitrogen () is converted into ammonia (). It occurs both biologically and abiological nitrogen fixation, abiologically in chemical industry, chemical industries. Biological nitrogen ...

Description

''Coriaria arborea'' is a large shrub that grows pairs of long, glossy leaves on branches, which measure between long. It has flowers that droop from spikes of up to in length, with black-coloured fruits.

Taxonomy

The species was first described by

William Lauder Lindsay Dr William Lauder Lindsay FRSE FLS LRCS (19 December 1829 – 24 November 1880) was a Scottish physician and botanist. As a physician he largely worked in the field of mental health. As a botanist he specialised in lichens. Life He was born o ...

in 1868. ''Coriaria arborea'' has two recognised subspecies, '' Coriaria arborea'' var. ''arborea'', and ''Coriaria arborea'' var. ''kermadecensis'', the latter found on the

Kermadec Islands The Kermadec Islands ( ; ) are a subtropical island arc in the South Pacific Ocean northeast of New Zealand's North Island, and a similar distance southwest of Tonga. The islands are part of New Zealand. They are in total area and uninhabit ...

Ecology

''C. arborea'' plays host to several species of New Zealand endemic moth including '' Izatha austera'', ''I. churtoni'', '' I. mesoschista'' and '' I. peroneanella''.

Distribution and habitat

''Coriaria arborea'' is endemic to New Zealand. It is the most common species of ''Coriaria'' in New Zealand, and tends to establish itself in disturbed land.

Uses

In spite of its toxicity, Tutu was consumed by

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 ...

, specifically the extracted

juice Juice is a drink made from the extraction or Cold-pressed juice, pressing of the natural liquid contained in fruit and vegetables. It can also refer to liquids that are flavored with concentrate or other biological food sources, such as meat ...

from the fleshy flower petals. The gathered berries were placed in specially woven baskets (called pū tutu) lined with the flower heads of

Toetoe ''Austroderia'' is a genus of five species of tall grasses native to New Zealand, commonly known as toetoe (from Māori).

, acting as a sieve to separate the poisonous seeds from the squeezed juice. The extracted juice is used as a sweetener to foods such as fernroot or was boiled together with seaweed and left to set as a black jelly called ''Rehia''.

Toxicity

The toxin

tutin Tutin may refer to: Places *Tutin, Serbia, town in Serbia Surname * Arthur Tutin (1907–1961), English footballer *Dorothy Tutin (1930–2001), English actress *Mary Tutin, maiden name of Mary Gillick (1881–1965), English sculptor *Tom Tutin ...

is found in all parts of the plant apart from the fleshy flower petals. Tutu has been responsible for the most cases of

livestock Livestock are the Domestication, domesticated animals that are raised in an Agriculture, agricultural setting to provide labour and produce diversified products for consumption such as meat, Egg as food, eggs, milk, fur, leather, and wool. The t ...

poisoning by any New Zealand plant. Dogs and even two circus elephants have been poisoned by the plant. On occasion human poisoning has occurred through consuming honey where bees had interacted with the plant. In 2014, a hiker in

Auckland Auckland ( ; ) is a large metropolitan city in the North Island of New Zealand. It has an urban population of about It is located in the greater Auckland Region, the area governed by Auckland Council, which includes outlying rural areas and ...

, New Zealand looking to taste supplejack, mistakenly chewed the

asparagus Asparagus (''Asparagus officinalis'') is a perennial flowering plant species in the genus ''Asparagus (genus), Asparagus'' native to Eurasia. Widely cultivated as a vegetable crop, its young shoots are used as a spring vegetable. Description ...

-looking young shoot of a tutu. He said he did not actually eat any of the plant because of the revolting taste, but within hours he had multiple tonic-clonic seizures (one of which dislocated his arm) along with labored breathing. Academic experts concluded he was lucky to survive the poisoning. A year later he had recovered fully apart from having some trouble with his memory. Honey becomes contaminated when bees collect honeydew secreted by the passionvine hopper insect that feeds off the tutu plant. People have occasionally been hospitalised or even killed by honey contaminated with tutin. 1974 was the last case of commercial honey poisoning where 13 people were poisoned. Since 1974 there have been nine other cases of honey poisoning, with the most recent occurring in 1991 in the

Bay of Plenty The Bay of Plenty () is a large bight (geography), bight along the northern coast of New Zealand's North Island. It stretches from the Coromandel Peninsula in the west to Cape Runaway in the east. Called ''Te Moana-a-Toitehuatahi'' (the Ocean ...

and 2008 in the

Coromandel Coromandel may refer to: Places India *Coromandel Coast, India ** Presidency of Coromandel and Bengal Settlements **Dutch Coromandel * Coromandel, KGF, Karnataka, India New Zealand *Coromandel, New Zealand, a town on the Coromandel Peninsula *Cor ...

. Periods of drought increase the risk of poisoning.

Gallery

Coriaria_arborea.jpg, ''Coriaria arborea'' with developing berries King, Martha The tutu, (commonly called toot) in flower.jpg, Botanical illustration of ''Coriaria arborea'' Coriaria arborea Linds. (AM AK339676).jpg, Herbarium specimen Coriaria arborea 501303551.jpg, Tutu fruit Coriaria arborea 506033376.jpg, Tutu leaves

References

{{Taxonbar, from=Q3755414 Coriariaceae Endemic flora of New Zealand