Karura Forest #3: Spiny Tree (Kapok)
The cache, a small cylindrical camo-container, is hidden at the foot of this impressive, interesting and incredibly useful tree.
For background information on Karura Forest including access, fees, features, a detailed trail map and useful links, see GC4PD3V Karura Forest #1: Intro, Info & Entry
The kapok or (red) silk-cotton tree (Bombax) Ceiba pentandra Linn. known as Msufi in Swahili, originated in tropical America. Although it was thought originally to have been introduced to Africa, it is native to western and central Africa. How the tree crossed the Atlantic Ocean is uncertain, but the fruits float and may well have been transported by ocean currents. It was domesticated in West Africa, from where it spread to East Africa and Asia. It is now cultivated all over the tropics, but mainly in South-East Asia, especially in Indonesia and Thailand. and is likely to be found in all tropical African countries.
There are several varieties and cultivars of this deciduous tree and it is not known which this one is. Depending on the type, they can grow into huge trees up to 70m tall with huge buttresses. It thrives at altitudes below 500m but can be found up to 4,000m. It occurs in rainforest, and gallery forest in drier areas. It is a pioneer in secondary forest and riverine forest, and is rarely found in primary forest. It grows fast in canopy openings caused by disturbance, becoming an emergent in mature stands.
Its bark is grey, flaky and covered with caducous (easily detached) conical spikes. Depending again on the species, flowers may be dark red, pink, white or creamy yellow, solitary or in fascicles usually on leafless branches. The fruit is a 5-valved woody capsule, densely woolly within with many seeds.
It is an incredibly useful (but often underutilised) tree with all parts having some value . . . and is an important export product for several African countries (eg. Ghana & Nigeria)
Commercial Uses
It is an important source of timber and of kapok fibre.
The fibre (floss) from the inner fruit wall is used for stuffing cushions, pillows and mattresses, and for insulation, absorbent material and tinder. Its use 
declined in the late 20th century with introduction of synthetic substitutes. However, there is renewed interest in its potential using new processing techniques, especially in textile applications. It may also have potential as a biodegradable alternative to synthetic oil-absorbent materials, due to its hydrophobic-oleophilic properties.
As timber is mostly used in plywood manufacturing, but also for making boxes and crates, for lightweight joinery and for papermaking. Traditionally, entire trunks are hollowed out as dugout canoes, and the wood is used for lightweight furniture, utensils, containers, musical instruments, mortars, carvings and similar items. It is suitable for insulation, wooden sandals, heels, rafts, floats, lifeboats, models, insulation and particle board. The buttresses (found in the larger species) are made into doors, table tops, plates and trays.
It is not a good fuel wood because it only smoulders but it can be used for fumigating huts or clothes. The wood ash is used as kitchen salt and for soap making. The bark is used for making hut walls and doors and yields a gum and a reddish brown dye. Leaves and shoots are fodder for goats, sheep and cattle. The leaves, flowers and young fruits are eaten cooked into sauces. The flowers are visited by bees, producing an amber-coloured honey with a characteristic 
taste. Ash from the fruits is locally made into snuff.
A use that has attracted commercial interest is as a source of seed oil, which has been used in soap, pharmaceutical manufacturing, illumination, paint manufacturing and lubrication. Seed cake is a good animal feed and fertilizer.
Medicinal Uses
It also has an extraordinary ranges of uses and is highly reputed in traditional medicine systems around the world, including Ayurveda, Unani, Siddha, Chinese, Tibetan - and African . Different parts of the tree (root, bark, gum, leaves, leaf sap) are used for leprosy, diarrhoea, dysentery, dysmenorrhoea, hypertension, emetic and antispasmodic, mouthwashes for toothache and mouth problems, hernia, gonorrhoea, heart problems, oedema, fever, asthma and rickets, skin infections, wounds, astringent, abortifacient, emollient, sedative, scabies, fatigue, lumbago, laxative, mental illness, stiffness of the limbs, headache, bleeding of pregnancy, eye-bath to remove foreign bodies from the eye, conjunctivitis, fever, intestinal parasites, stomach-ache!
The fibre is used for cleaning wounds and seed oil is rubbed in for treatment of rheumatism and applied to heal wounds.
There is even an entire book devoted to 'Pharmacology of Bombax Ceiba Linn' written in 2012 by Indian scientists which gives an idea of its medical importance.
Other uses
It is also planted as a wayside and shade tree and sometimes left by farmers after clearing the forest for agricultural land, to serve as a shade tree for cultivation of crops such as coffee and tea. It is increasingly planted as an ornamental tree in subtropical areas. It also has sacred significance for local peoples in many parts of the world, including tropical Africa, where it often serves as a tree under which meetings are held.
See here and here for more detailed information on this fascinating tree.