Macadamia tetraphylla - Rough macadamia

Description and Uses

Macadamia tetraphylla (Rough macadamia) is a tropical tree from Northern Australia . It is mainly grown for its nut crops , which have a long shelf life. The crop is harvested by ground gathering. It starts flowering after 7 - 9 years. The yield will be 1kg/tree, but in its top season there will be a yield of 20kg/tree. Other crop types include; ornamental, oil, nut, . The seed/nut is used as delicacy . The seed/nut is used as " high vitamin-C content, " with oleic acid (60%/oil - 67%/oil) as its significant phytochemical. There is macadamia oil extracted by cold pressing from the tree's seed/nut yielding 60% - 70% oil. The tree's wood is called macadamia wood and has a density of 550 - 800 kg/m³. Regarding firewood production the tree's growing speed is slow, it's energetic value is 3000 ckal/kg and the wood's drying speed is medium. After 70 years the tree can be totally removed as it reached its commercial and ecological goal. Macadamia tetraphylla has a lifespan of 200 years.

Environmental limitations

The tree is 18 meters tall with a crown of 15 meters wide. The tree prefers a planting distance of 600 cm and a row distance of 1,400 cm. It is slow growing and intolerant to shade. Macadamia tetraphylla has a shallow root-system and it has symbiotic associations with the Glomus intraradices fungi (endo-mycorrhiza). It is not able to fix nitrogen with "any bacteria. The name(s) or string of bacteria include(s) "not applicable ". The tree's flower-morphology is hermaphroditic and is pollinated by bees. Macadamia tetraphylla is evergreen and not allelopathic and has no thorns.

Macadamia tetraphylla thrives in an altitude of 5 to 2000 meters above sea-level (tropical). The minimum temperature is -2°C; optimally between 15 - 29°C. The optimal rainfall is 2000 mm/year. Without irrigation the annual rainfall should be between 700 - 2600mm (L/m²). The optimal soil-pH is between 5.0 - 6.0 in a soil texture of loam. To salt it is intolerant to wind intolerant and to fire intolerant.

Pests and Diseases

Macadamia tetraphylla is susceptible to the following pests: Homoeosoma vagella , Amblypelta nitida , Amblypelta lutescens , Cryptophlebia ombrode , Eriococcus ironsidei . And it's susceptible to the following diseases: Blossom end rot , Soybean mosaic virus , .

Seed Propagation

Seeds are orthodox and can be stored for 6 months. There are approximative 325 seeds/kg. The seeds can be propagated as followed:

• (1) Store harvested seeds in water or in the fruit at room temperature
• (3) Remove the seeds from cold to a permanent warm temperature.
• (2) Soak the seeds overnight in warm water before sowing.