Bombax ceiba

Bombax ceiba, like other trees of the genus Bombax, is commonly known as cotton tree. More specifically, it is sometimes known as Malabar silk-cotton tree; red silk-cotton; red cotton tree; or ambiguously as silk-cotton or kapok, both of which may also refer to Ceiba pentandra.

This Asian tropical tree has a straight tall trunk and its leaves are deciduous in winter. Red flowers with 5 petals appear in the spring before the new foliage. It produces a capsule which, when ripe, contains white fibres like cotton. Its trunk bears spikes to deter attacks by animals. Although its stout trunk suggests that it is useful for timber, its wood is too soft to be very useful.

Bombax ceiba grows to an average of 20 meters, with old trees up to 60 meters in wet tropical regions. The trunk and limb bear numerous conical spines particularly when young, but get eroded when older. The leaves are palmate with about 6 leaflets radiating from a central point (tip of petiole), an average of 7–10 centimetres (2+5⁄6–4 in) wide, 13–15 centimetres (5+1⁄6–5+5⁄6 in) in length. The leaf's long flexible petiole is up to 20 centimetres (8 in) long.

Cup-shaped flowers solitary or clustered, axillary or sub-terminal, fascicles at or near the ends of the branches, when the tree is bare of leaves, an average of 7–11 centimetres (2+5⁄6–4+1⁄3 in) wide, 14 centimetres (5+1⁄2 in) in width, petals up to 12 centimetres (4+2⁄3 in) in length, calyx is cup-shaped usually 3 lobed, an average of 3–5 centimetres (1+1⁄6–2 in) in diameter. Staminal tube is short, more than 60 in 5 bundles. The stigma is light red, up to 9 centimetres (3+1⁄2 in) in length, ovary is pink, 1.5–2 centimetres (2⁄3–5⁄6 in) in length, with the skin of the ovary covered in white silky hair at 1mm long. Seeds are numerous, long, ovoid, black or gray in colour and packed in white cotton.

The fruit, which reaches an average of 13 centimetres (5 in) in length, is light-green in color in immature fruits, brown in mature fruits.

The tree is widely planted in southeastern Asian countries and regions (such as in Myanmar, Nepal, Thailand, Vietnam, Malaysia, Philippines, Indonesia, southern China and Taiwan, etc.). According to Chinese historical record, the king of Nam Yuet (located in the southern China and northern Vietnam nowadays), Zhao Tuo, gave a tree to the emperor of the Han dynasty in the 2nd century BC.

This tree is commonly known as Let-pan (Burmese language: လက်ပံ), semal (Hindi: सेमल), (Hindi: सीमल),shimul (Bengali: শিমুল) or ximolu (Assamese: শিমলু) in India. It is widely planted in parks and on roadsides there because of its beautiful red flowers which bloom in March/April. This tree is quite common in New Delhi although it doesn't reach its full size of 60m there because of the semi arid climate. The cotton fibers of this tree can be seen floating in the wind around the time of early May. This tree shows two marked growth sprints in India: in spring and during the monsoon months. Perhaps due to subtropical climate and heavy rainfalls, it is found in dense populations throughout the Northeast India. In Myanmar, its flowers are let to be dry and cooked, which is one of the traditional foods of Myanmar.

This tree is also found in the eastern parts of Pakistan, especially in the eastern city of Lahore. The local Urdu and Punjabi names for the tree is sumbal.