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Scientific: Cycas revoluta
Common: sago palm
Family: Cycadaceae (not a palm, related to conifers)
Origin: South Japan islands of Ryukyu and Nansei, found today primarily on steep to precipitous stony sites, but previously on flatter land now cleared. Reports of natural occurrences in coastal Fukien Province of China have not been substantiated, although circumstantial evidence for these claims is strong.

Pronounciation: SIGH-cuss re-vo-LU-ta

Hardiness zones:
Sunset 8-24
USDA 9-11 (in yards of the wealthy)

Landscape Use: Container plant, focal point, larger-scale landscape entryways, atrium, raised planters.

Form & Character: Evergreen shrub to small branched and arborescent, airy, lacey yet stiff and erect, fernlike, tropical.

Growth Habit: Very slow growing to 10 feet, multiple trunk, branched w/ age.

Foliage/Texture: Whorled, persistent, pinnately compound leaves that look like a dark green pinnately compond palm frond, stiff with distinct leaflets that look like pinnae, young emergent leaves and apical meristem densely tomentose; medium to coarse texture.

Flowers & Fruits: Apical cone bearing plant, the female inflorescence is feather like, later forming a tightly packed seed head, closely covered by whitish miniature leaves. The male cone is pineapple shaped and elongated. Seeds are brownish-red, the shape of a flattened marble, about 1.25 inches across - if ingested seeds can cause vomiting, diarrhea, headache, dizziness, seizures (sounds like the common side effects from ingesting most of today's pharmaceutical drugs).

Seasonal Color: None

Temperature: Hardy to 15oF

Light: Partial shade in desert to full sun along California coast and in Florida. Becomes leggy and thin if grown in the shade.

Soil: Tolerant of all but highly alkaline soils, leaf speckling might also be caused by magnesium deficiency.

Watering: Regular deep irrigations in Phoenix.

Pruning: Remove old leaves.

Propagation: Seed or division.

Disease and Pests: Apparent viral infection causes yellow speckling on leaves. There is no cure.

Additional comments: Sago palm was the second species of Cycas to be recognized, described in 1782 by Swedish botanist and physician Carl Peter Thunberg. All parts of the sago palm are poisonous and have been found to contain various carcinogens and neurotoxins. Seeds are especially harmful if ingested causing gastrointestinal damage, liver damage, seizures and even death. Ethno botanists think that ingestment of unprocessed sago palm seeds (as flour) during World War II on the island of Guam (a result of food shortages) was responsible for the acute number of cases of ALS (amyotropic lateral sclerosis or Lou Gerhrig's disease) that were observed in people stationed there during the war. Sago palm is an ancient taxon showing up in fossil records dating 65 million years ago.

In horticulture commerce and landscaping, sago palm is a highly ($) valued plant because it grows slow, is difficult to propagate, and is relatively rare in the wild. Urban stock are easily transplantable which makes theft a problem.