Haldu (Haldina Cordifolia/हळदू, हेदू, गिरीकदंब) is a deciduous tall tree with a large crown and is the sole species in the genus Haldina. The tree has long, straight, clean bole and is often buttressed & fluted at the base. The buttresses are sometimes of irregular and fantastic shapes. When growing in more isolated positions it produces a thick bole and massive branches with a large spreading crown.
Leaves are opposite, broadly ovate, heart shaped glossy green in colour. Flowers are tiny, yellow, in globose pedunculate heads and fragrant with protruding stigmas. The new leaves give a magnificent look, followed by creamy yellow flowers. The tree attracts lots of bees and insects and subsequently birds. The grey or light-black bark is startling yellow when freshly cut but turns pale red-brown on exposure. Hence the name Turmeric wood or Yellow teak.
Haldu has a striking similarity with Kaim (Mitragyna Parvifolia/कळम) as the flowers and leaves appears almost same. But the leaves of Haldu are nearly circular, heart-shaped at base and with a pointy tip. Also there is difference in the stigma of flowers, if closely admired!
Natural regeneration of this species is difficult as the tiny seeds as well as young seedlings in forests are easily washed away. The proportion of seedlings which survive and establish themselves in forests is relatively very small. Further available trees are cut due to demand for its wood, which is reported to be acid-resistant, making it suitable for use as laboratory bench tops etc.
Haldu is propagated by seeds. Seed is very small and so should only just be covered with soil. The seed is best sown in a seed-box that is placed in light shade and protected from heavy rain. It should be watered carefully with a very fine spray. Germination ordinarily takes place in about 20 - 40 days. Young seedlings grow very slowly in their first year and are very susceptible to being washed away or beaten down with rain at this time. Plants develop a thin but long tap root in their first year, this thickens and develops considerably in the second year. Growth is faster in the second year and onward.
Young trees prefer a position in light to moderate shade, but become more light demanding as they grow older. It succeeds in most of the soils but well-drained soil, growing best in deep, fairly fertile conditions. For instance, on lower slopes of hills among boulders. Usually growing along rivers or transitional areas between swampy wetlands and dry loamy areas, which are flooded for short periods. The tree has a massive tap-root system in proportion to its size, which makes it very resistant to drought. The tree can tolerate temperatures within the range of 5°- 47°C.
The Yellow Teak is also harvested for local medicinal use. It pacifies vitiated pitta and known to be useful in inflammation, urinary retention, wounds and ulcers, skin diseases, biliary colic, infection, dysentery, fever and burning sensation.
Haldu is often planted as ornamental, avenue tree and even for its shade. But the tree is potentially great agroforestry species too! The tree produces fuel wood and fodder for livestock. It can be coppiced within limits. It provides good amount of green manure. It yields a yellow dye, which was used for dyeing wool and linen. In some parts of India, the tree has a religious significance in Hindu marriage rituals.