''Macadamia jansenii'' is an endangered and poisonous

tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are ...

in the

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. They include all forbs (flowering plants without a woody stem), grasses and grass-like plants, a vast majority of ...

family Proteaceae, native to

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_ ...

in Australia. It was only described as a new species in 1991, being first brought to the attention of plant scientists in 1983 by Ray Jansen, a sugarcane farmer and amateur botanist from

South Kolan South Kolan is a rural locality in the Bundaberg Region, Queensland, Australia. In the , South Kolan had a population of 1,061 people. Geography The South Kolan region is in the Wide Bay–Burnett region, north of the state capital Brisbane a ...

in Central

. Closely related to the cultivated and recently domesticated macadamia nut, it has small 11–16 mm diameter nuts that have a smooth, hard, brown shell enclosing a cream, globulose

kernel Kernel may refer to: Computing * Kernel (operating system), the central component of most operating systems * Kernel (image processing), a matrix used for image convolution * Compute kernel, in GPGPU programming * Kernel method, in machine lea ...

that is bitter and inedible. In the wild it grows as a multi-stemmed 6–9m tall evergreen tree, with leaves having entire margins and generally in whorls of 3. An extremely rare species, it was discovered as a single population of around 60 plants in the wild in

Eastern Australia The eastern states of Australia are the states adjoining the east continental coastline of Australia. These are the mainland states of Victoria, New South Wales and Queensland, and the island state of Tasmania. The Australian Capital Terr ...

. In 2018 about 60 new mature ''Macadamia jansenii'' trees were located,Amateur naturalist finds new population of endangered wild macadamias
''ABC News'', 19 February 2019; Retrieved 22 September 2022. although a quarter of these were destroyed in the bush fires of 2019. Sequencing of the genome was carried out, as knowing the genotype of wild crop relatives is critical to diversification of crop genetics to ensure food security, producing a 751 Mb reference genome assembled to 14 chromosomes. This is a potential model to study the diversity of a whole species, helping understand the impact of small population size and the associated genetic bottlenecks. Currently there are only around 100 known trees in existence in the wild, all growing in Bulburin National Park, near

Miriam Vale Miriam Vale is a rural town and locality in the Gladstone Region, Queensland, Australia. In the , Miriam Vale had a population of 512 people. Geography The town is situated on the Bruce Highway, north of Brisbane, the state capital, and sout ...

, although an insurance population propagated from cuttings has been established at the Tondoon Botanic Gardens, near

Gladstone William Ewart Gladstone ( ; 29 December 1809 – 19 May 1898) was a British statesman and Liberal politician. In a career lasting over 60 years, he served for 12 years as Prime Minister of the United Kingdom, spread over four non-con ...

References

jansenii Flora of Queensland Proteales of Australia Trees of Australia {{proteaceae-stub

See also

References