BAMBANG IRAWAN, FRANZ GRUBER
Georg-August-Universität Göttingen, Institute of Forest Botany, Germany
Ironwood (Eusideroxylon zwageri TEIJSM. & BINN.) is a threatened tree species which grows in tropical lowland forest. Over-exploitation caused decreasing its population. Most of mature trees were felled which leads to decreasing number of seed production and lost of genetic resources. A research on sprouting ability of ironwood varieties had been conducted to evaluate sprouting ability and its importance in ironwood conservation and development. Ironwood varieties have been recognised by local people and also reported by many scientists since in the middle of 19th century. Local people recognised four varieties of ironwood which grow in Senami forest, Jambi Indonesia namely daging, kapur, sirap and tanduk. The meaning of those vernacular names is directly related to wood or bark structure of each variety. The research had been conducted at Senami forest using systematic plot survey. Research results obtained that all of ironwood stumps produced sprouts. Sirap was the most dominant variety which sprouting (85.71%) which followed by daging (35.71%), kapur (17.86%) and tanduk (10.71%). The number of sprouts was slightly different from one to another variety. The highest number of sprouts belonged to daging followed by sirap, kapur and tanduk variety. Sprouts tended to grow faster than seedlings. For the first year, they grew 2.87 and 5.64 times in diameter and height respectively. After investigating and discussing sprouting ability of ironwood, it can be concluded that sprouting is very important for ironwood since it faces very intensive threats. It is very important for regeneration, stand restoration, genetic resource conservation, propagation and development of ironwood.
Keywords: Conservation, genetic resources, ironwood varieties, sprouts and sprouting ability