Cycad (Cycad) - Cycas revoluta; cycad

Japanese: ソテツ(蘇鉄) - ソテツ（英語表記）Cycas revoluta; cycad

An evergreen shrub of the Cycadaceae family. It grows naturally on coastal cliffs in the Ryukyu Islands and southern Kyushu. It is widely cultivated in warm regions as a garden or park tree, and is sometimes grown in a pot for decoration. The stem is thick and cylindrical, 1-4 m tall, and the surface is black-brown with densely-spaced leaves of dead leaves. The leaves are pinnately compound, 1-1.5 m long, and grow in clusters at the top of the stem, with dark green, stiff, linear leaflets that spread out magnificently on all sides. The plant is dioecious, and flowers grow at the top of the stem in summer. The male flowers are cylindrical, consisting of many long, scale-like leaves (corresponding to stamens), and reach a length of 40 cm. The leaves have many anthers on the underside. The female flowers are about 15 cm long and are a collection of carpels that are slightly palmately lobed, and each carpel produces 2-3 pairs of ovules at the base of the leaf margin. After pollination, the pollen remains in the pollen chamber in the female flower for a long time, but when it germinates, sperm are produced in the pollen tube and fertilization occurs. The seeds are slightly flattened and oval in shape and ripen to a crimson red color. The seeds are roasted and eaten, and the pith of the stem is crushed to extract starch as a famine plant.

Source: Encyclopaedia Britannica Concise Encyclopedia About Encyclopaedia Britannica Concise Encyclopedia Information

Japanese:

ソテツ科の常緑低木。南西諸島や九州南部の海岸の断崖などに自生する。庭木や公園樹として暖地で広く栽植され，また鉢植にして観賞することもある。茎は太い円柱状で高さ1～4m，表面には枯れ落ちた葉の基部が密に残り，黒褐色をしている。葉は長さ1～1.5m，茎頂に集ってつき，濃緑色で硬い線形の小葉から成る羽状複葉で四方に壮大に広がる。雌雄異株で，花は夏に茎頂につく。雄花は多数の長い鱗片状の実葉 (おしべに相当する) から成る円柱状で，長さ 40cmに達する。実葉の下面には多数の葯 (やく) がある。雌花は長さ約 15cm，やや掌状に裂けた心皮の集合で，各心皮の基部葉縁には2～3対の胚珠を生じる。受粉後，花粉は長期間雌花内の花粉室にとどまるが，やがて発芽すると花粉管中に精子を生じ受精する。種子はやや平らな卵形で朱紅色に熟する。種子はあぶって食べ，また救荒植物として茎の髄を砕いてデンプンをとることもある。

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