King Sago

Cycas revoluta Thunb.

SIGH-kass rev-oh-LOO-tah

Cycads - Cycadaceae

Explanation of name: According to HUX, the generic name comes from Greek koikos, in reference to koix, the Doum Palm. Revoluta refers to the curled (revolute) leaflet margins.

Natural range: Japan (HUX), also in China but probably from cultivation (WH2). Steep seashore limestone cliffs or low shaded forests (WH2).

Recognition: Similar to a short palm (to about 6’ tall) with stiff, glossy, pinnate leaves having sharp-tipped leaflets. The leaflet margins are curled under, and the leaflets are fuzzy on the undersides (in contrast with C. circinalis). The plants are dioecious (separate male and female plants), with the male cones resembling large ears of corn, and the female cones loose and leafy, bearing large toxic yellowish seeds marginally on the irregularly pinnate cone-leaves.

Landscape uses: Used like a small palm alone or in clusters, often accenting buildings. Usage undermined by the Aulacapsis Cycad Scale, which can ruin these plants if they are not treated intensively. The plants and seeds are toxic.  Pollination by a male is required for fertile seeds---artificial pollination by dusting works well (WH2).  After ripening the seeds need 4-5 months to mature, then another month to germinate (WH2). Fast-growing for a Cycad.  WH2 mentions 10’ in 15 years under ideal conditions.

Note: The plants form “coralloid roots” that rise vertically from beneath the canopy. The roots house symbiotic blue-green-bacteria that assist with nitrogen fixation.

            Cycas and other cycads are Gymnosperms (plants with seeds but no flowers or fruits), a feature they share with conifers, ginkgo, and a small number of additional plants.