Aloe arborescens

Aloe arborescens.

The Krantz aloe is native to southern Africa.
It is naturalised in S.E. Queensland where it is a minor environmental weed.
They are common in Brisbane mostly in waste areas and beside roads.
They can be variable with some subspecies and forms described.

A single plant can have a stem up to 3 to 4 m long that usually branches.
Each branch has a terminal rosette of leaves with dead leaves below it.
They sucker freely to produce large clumps that can be metres wide and deep.
Young stems are green and older ones are greyish-brown and slightly woody.
Stems are typically erect but it depends on their situation and length.

The mostly spreading succulent leaves are arranged in a spiral with sheathing bases.
They are up to 60 cm long and taper from a 6 to 7 cm wide base to a pointed tip.
They curve backwards and from above are straight or curved sideways (falcate or sickle-shaped).
Leaves are dull green, grey-green or blue-green while in harsh conditions they may redden.
The smooth surface has no spots which helps separate then from the other commonly seen species.
There are 3 to 5 mm high pale teeth around the whole edge.

Inflorescences are a leafless scape up to 60 to 80 cm long.
Each plant can have 1 to 3 scapes that may occasionally branch once.
The scape has bracts up to 2 cm long.
Each branch has a conical raceme up to around 25 cm long and 12 cm wide at the base.
A raceme can have over 100 closely spaced flowers that open first at the bottom of the spike.
Flowers are on a pedicel over 7 mm long and up to 4.5 cm.

The cylindrical flowers are 3 to 4 cm long.
From around 7 mm wide around the ovary the perianth tube constricts slightly above it then widens a little to the mouth.
Flowers have 6 tepals in 2 whorls of 3 with those in the outer whorl being free of each other and the inner tepals.
The inner tepals are fused for 3 to 3.5 cm with spreading lobes around 13 mm long and 3 mm wide.
Depending on the form flowers may open red then age to pink then yellow or orange or they may open a yellowish-brown.

There are 6 stamens up to 3.5 cm long with anthers around 3 mm long.
The superior ovary has a single style.
The anthers and stigma lie outside the perianth tube for up to 5 mm.

The fruit are said to be dark brown to black ellipsoidal capsules around 1.5 cm long.
The red-brown seeds are around 4 mm wide.