Ruscus aculeatus, commonly called butcher's broom, knee holly or piaranthus, is a prickly, mounded, rhizomatous, suckering, evergreen sub-shrub that is native to Europe, the Black Sea area, northern Africa and the Azores. It typically grows to 2-3' tall and as wide. The actual leaves of this shrub are microscopic. The ovate, thick, spiny-tipped, glossy dark green, leaf-like structures (to 1 1/2" long) look like leaves but are in fact flattened leaf-like shoots (modified stems) called cladophylls on which the flowers and fruits are borne. Six-tepaled, star-shaped, greenish-white flowers (1/16" across) bloom singly or in pairs on the upper sides of the cladophylls in spring. Flowers are not showy. Female or hermaphrodite flowers are followed by showy, spherical to oblong, waxy red berries (3/8" across) which mature from late summer to winter.
Common names for this shrub include butcher's broom (bunches of stems were once used to clean butcher blocks) and knee holly (shrub rises to knee level and features prickly, evergreen, leaf-like cladophylls reminiscent of holly leaves).