Allocasuarina humilis

Location & distribution maps

Wikipedia links:       Angiosperms > Eudicots > Rosids  > Fagales > Casuarinaceae > Allocasuarina  humilis

Other links:     

Common name:         Dwarf She-oak

Conservation status: ...

Etymology:   

• The specific epithet (humilis) means "low, or low-growing"

Flowers

• Male flowers are arranged in spikes 6–18 mm long, in whorls of 12 to 16 per centimetre 

• The anthers 0.7–0.8 mm long

• Flowering occurs from May to November

Fruit:                            

• The mature cones are sessile, 12–22 mm long and 10–17 mm in diameter containing samaras 5–6 mm long with a short wing

Leaves:         

• The leaves reduced to scale-like teeth 0.4–0.5 mm long, arranged in whorls of five to seven around the branchlets

Stem & branches: 

• Its needle-like branchlets are more or less erect, up to 120 mm long, 

• The branchlets are smooth and sometimes waxy

• The sections of branchlet between the leaf whorls (the "articles") are mostly 3–6 mm long and 0.8–1.2 mm wide

Roots:         

Habit:        

• An erect or spreading, dioecious or monoecious shrub that typically grows to a height of 0.2–2 m 

Habitat:   

• It grows on sand, sand over laterite, gravel, or clay

Distribution:                  

• It is found across southwest Western Australia

• From the Murchison River in the north, to the south coast, where it extends eastwards to Israelite Bay

Additional notes:     

• Taxonomy

  • This sheoak was first formally described in 1841 by Christoph Friedrich Otto and Albert Gottfried Dietrich, who gave it the name Casuarina humilis in their book Allgemeine Gartenzeitung

  • In 1982, Lawrie Johnson transferred it to the new genus Allocasuarina as A. humilis in the Journal of the Adelaide Botanic Gardens

  • A 2003 molecular study of the family Casuarinaceae showed dwarf sheoak and horned sheoak (A. thuyoides) to be sister taxa, and form a clade with A. thuyoides, A. microstachya, karri oak (A. decussata) and western sheoak (A. fraseriana),[10] all from Western Australia

• Use in horticulture

  • Allocasuarina humilis adapts readily to cultivation

  • Versatile, it tolerates a wide range of soils, including those with some alkalinity, and prefers a sunny aspect

  • Tolerant of some exposure to coastal conditions, it is also planted for erosion control and as a windbreak

  • Unlike many Australian native plants, it is relatively tolerant of phosphates to some degree in cultivation

Sources of information:

•  https://en.wikipedia.org/wiki/Allocasuarina_humilis (August 2024)