Identifying Commonly Cultivated Palms

Common Name

Alexander palm, Solitaire palm

Description

Stems: Solitary, slender, gray stems to 10 m tall and up to 12 cm in diameter, bulging at the base, with ridged rings of leaf scars. Leaves: Pinnate, reduplicate, to 3 m long, with an arching rachis holding regularly arranged leaflets at a slightly ascending, V-shaped angle, in a single plane. The crown shaft is about 60 cm long, somewhat swollen at the base, and light green with a waxy white coating. Leaflets are green above and grayish green below, widest toward the middle, pleated by deep secondary veins, with thick marginal ribs and prominent midribs with brown or tan twisted ramenta on the underside. Leaflet tips are truncated and jagged (praemorse). Flowers and fruits: Inflorescence is pendulous, to 1 m long and branched to two or three orders. White male and female flowers are borne on the same inflorescence. The spherical, red fruits are 1.5-2 cm long and have remnants of the stigma at the apex.

Diagnostic Features

Slender, solitary, gray stemed palms with pinnate leaves, a short crown shaft with a waxy white coating, and pleated, praemorse leaflets that are are green above and grayish green below.

May be confused with

Ptychosperma macarthurii, but it is a smaller statured, clustering palm with drooping rather than ascending leaflets.

Distribution

Native to Australia

Additional Comments

This species is commonly cultivated and commonly hybridizes. It is found in tropical landscapes, including in Hawaii

The Florida Exotic Pest Plant Council lists this species as a Category II invasive: exotic plants that show signs of increasing in abundance, but that have not yet altered native plant communities. www.fleppc.org