Increasing scarcity of wood such as ironwood (Eusideroxylon zwageri Teijsm and Binn) is very alarming. We have to kind of tree regeneration ulin still rely heavily on natural regeneration potential, whereas the artificial regeneration on a large scale had never been done. That the type of flowering time in different places ulin irregular. So very difficult to rely on artificial regeneration of generative with seeds. Seed ulin take a long time sometimes up to one year to germinate. There are two kinds of difficulties that arise for the regeneration of ulin. First, how to get the plants growing together with the seeds that germinate very slowly and irregularly. Second, how to ensure the necessary shade to the process of germination and early growth and so on.
