Bombax ceiba (red silk cotton tree, "Indowatanoki")

Japanese name: インドワタノキ
Scientific name: Bombax ceiba

[Overview]
A deciduous tree 25 m tall.
It is said that some trees reach 60 m in their native range.
The bark is grayish white, and young trees have many conical thorns on the trunk.
With age, buttress roots develop.
The branches spread horizontally.
The leaves are alternate and palmately compound with 5–7 leaflets; the leaflets are elliptic, 10–16 cm long and 3.5–6 cm wide, pointed at the tip, pinnately veined, and entire.
The leaflet stalks are 1.5–4 cm long, and the leaf stalk is 10–20 cm long.
The flowers open before the leaves appear, borne singly in the leaf axils at the branch tips, and are 5-petaled, 10 cm across, bright red to orange-tinged red.
The petals are elliptic, fleshy, and recurved, and hairy on the outside.
The stamens are in 2 whorls; the outer whorl is divided into 5 bundles with 10 or more stamens per bundle, and in the inner whorl 10 stamens are fused in pairs and stand upright.
The filaments are pink and the anthers are yellow.
There is 1 pistil, and the stigma is 5-lobed.
The calyx is cup-shaped, 3–5 cm across, and 3–5-lobed.
The fruit is a capsule, elliptic, 10–15 cm long and 4.5–5 cm across, hairy, and splits into 5 when ripe.
The inside of the fruit is densely packed with white cottony hairs that enclose many seeds.

[Uses]
The cottony hairs of the seeds are used as stuffing for cushions and the like.
The flowers are edible.
The wood is soft and is used for woodwork.

[Cultivation]
Propagate from seed, cuttings, or layering.
It prefers sunny, well-drained soil, and in Okinawa it is planted along streets and similar places.
The branches break easily, so plant it in a place not exposed to strong wind.
Because the branches spread horizontally, a large space is needed.
It has poor tolerance of salt wind.
There are no particular pests or diseases.

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