Macadamia nut species

Names and Synonyms

Common Names

• Bush Nut
• Nut Oak
• Queensland Nut Tree
• Smooth-shelled Macadamia
• Bauplenut
• bopplenut
• macadamia-nut
• nut-oak
• poppelnut
• smooth-shell Queenslandnut
• Macadamia Tree

Scientific Names

Accepted name

Synonyms

• Macadamia ternifolia var. integrifolia

Regional and Traditional Names

Sources: Wikidata, Catalogue of Life

Taxonomical Classification

This plant belongs to the kingdom Plantae within the phylum Streptophyta and is classified under the class Equisetopsida. As a member of the subclass Magnoliidae and the order Proteales, it falls within the family Proteaceae. Specifically, its taxonomic identity is defined by the genus Macadamia, with the species being Macadamia integrifolia.

Sources: The World Checklist of Vascular Plants (WCVP)

Distribution

This plant exhibits a diverse geographical distribution spanning across two major continents. In Africa, its range extends through South Tropical Africa, specifically within Mozambique. It is also well-established in Southern Africa, where it can be found in the Northern Provinces and KwaZulu-Natal. Moving to the Australian continent, the species is widely distributed across the state of New South Wales. Furthermore, it maintains a significant presence throughout the subtropical regions of Queensland.

Sources: The World Checklist of Vascular Plants (WCVP)

Botanical Identification

Ecology

The ecology of Macadamia integrifolia is defined by its preference for specific altitudinal gradients and subtropical forest environments. This species thrives within a distinct elevational range, typically occurring from a minimum of 50 m AMSL to a maximum of 1500 m AMSL. Within these parameters, the plant is well-adapted to humid, frost-free climates where it often inhabits the subcanopy or canopy layers of rainforest ecosystems. Its distribution is closely tied to areas receiving consistent rainfall and well-draining, nutrient-rich volcanic or alluvial soils, which support its extensive root systems and long-term growth cycles in the wild.

Elevational range max:

1500 m AMSL

Elevational range min:

50 m AMSL

Life history

The life history of Macadamia integrifolia is characterized by its status as a perennial species, meaning it lives for many years and undergoes continuous growth cycles rather than completing a life cycle in a single season. As an evergreen plant, it maintains its foliage throughout the entire year, providing a consistent canopy that does not undergo a seasonal shedding process. This combination of a long-lived perennial lifecycle and evergreen habit allows the plant to establish a stable, long-term presence in its natural habitat, continuously producing leaves and contributing to the overall structure of the ecosystem over many successive years.

Deciduousness :

evergreen

Lifecycle :

perennial

Morphology

The morphology of Macadamia integrifolia is characterized by its growth form as a woody tree that is strictly terrestrial in its habitat. As a self-supporting organism, it does not function as a climber, liana, or vine, nor does it exhibit epiphyte or parasitic tendencies, maintaining an independent life cycle. The plant's stature is substantial, with a height that typically ranges from a minimum of 6 m to a maximum of 18 m, reaching a mean height of approximately 15 m.

Aquatic :

terrestrial

Climber :

self-supporting

Epiphyte :

terrestrial

Growth form :

tree

Parasite :

independent

Plant height max:

18 m

Plant height mean:

15 m

Plant height min:

6 m

Woodiness :

woody

Physiology

The physiology of Macadamia integrifolia is characterized by a C3 photosynthetic pathway, which dictates its carbon fixation processes and environmental adaptation strategies. The vegetative structure features leaves that exhibit significant morphological variability, with lengths ranging from a minimum of 7 cm to a maximum of 15 cm. These leaves are relatively narrow, possessing a width that varies between a minimum of 2 cm and a maximum of 4 cm. Furthermore, from a nutritional standpoint, the plant does not function as a nitrogen fixer, meaning it relies on external soil nitrogen availability rather than symbiotic nitrogen-fixing bacteria to meet its metabolic requirements.

Leaf length max:

15 cm

Leaf length min:

7 cm

Leaf width max:

4 cm

Leaf width min:

2 cm

Nitrogen fixer :

no

Photosynthetic pathway :

C3

Reproduction

The reproduction of Macadamia integrifolia is characterized by a complex biotic pollination syndrome, relying heavily on living organisms to facilitate the transfer of pollen. The process is primarily driven by insect vectors, with bees serving as a specific and critical component of the pollination mechanism. Because self-fertilization is absent in this species, successful fruit and seed production necessitates cross-pollination, making the presence of diverse insect populations essential for maintaining genetic diversity and ensuring reproductive success.

Pollination syndrome :

insect

Pollination syndrome :

bee

Pollination syndrome :

biotic

Self fertilization :

absent

Sources: Global Inventory of Floras and Traits (GIFT)

Chemicals

Macadamia integrifolia has 1 reported phytochemicals identified across 0 scientific publications and several other databases. The most consistently reported chemicals include Unsaturated Fatty Acids.

Unsaturated Fatty Acids

1. Food research international (Ottawa, Ont.)

Conditions

Macadamia integrifolia has 2 reported investigations on conditions identified across 0 scientific publications and several other databases. The most consistently reported conditions include inflammation, rheumatoid arthritis.

Inflammation

1. Pharmacognosy magazine

Rheumatoid arthritis

1. Pharmacognosy magazine