You see them in many places around Brisbane, including private gardens, but the tall Alexandra palm (Archontophoenix alexandrae) can grow up to 30m in height, with a crown containing around 10-12 long leaves that themselves can measure up to 4.5m.
Unfortunately, while they are native to northern parts of Queensland, the Alexander palm has become a weed species elsewhere, invading waterways and riparian zones (beside waterways) in coastal districts.
According to the Brisbane City Council Weed Identification Tool, this palm is also known by a range of other names, including Alex palm, Alexander palm, feather palm, king palm or the northern bangalow palm. However, this species should not be confused with the similar-looking bangalow palm, which has a darker-coloured base to its leaves (the bit closest to the trunk of the palm).
Its round or oval fruit usually measures 8-14 mm in length and 6-11 mm in width. They turn from green to bright red as they mature, losing their fleshy red outer covering as they age, exposing a fibrous brown under-surface. The round, brown seed is about 8 mm across.
Birds, bats and other animals graze on the fruit, helping to disperse them. However, experts believe that fallen fruit may be also carried far and wide by water or in discarded garden waste.
Source: Brisbane City Council Weed Identification Tool
Image: Trina McLellan