A Half-yearly Peer Reviewed Journal of Bangladesh Forest Research Institute
Sissoo (Dalbergia sissoo Roxb.) is a large deciduous tree which is planted throughout Bangladesh for its valuable timber. It grows well on alluvial soil, but it does not grow healthy in the soils of heavy texture (Bakshi 1976). The species can tolerate high soil moisture under well-drained conditions, but it can not withstand water-logging even for a short period (Street 1962). On the other hand, it can tolerate a long dry period. At Homna in Comilla, a road was newly constructed which was water-logged for a long time because of prolonged rainfall. The roadside strip plantations of D. sissoo, Swietenia macrophylla, Albizia procera, Cassia siamea, Acacia auriculiformis and Tertninalia arjuna were raised in June, 1990. The sissoo saplings were growing well with drak green bushy and spreading crowns. Some of them attained a height of about two metres. A wilt symptom first appeared in the last quarter of June, 1991 and it continued to September. By July, about 25% of the 8000 saplings began to wilt. About 5% of them died completely within August. At first the leaves of lower branches became yellowish and continued towards the apex. As a rusult, the entire saplings turned yellow. The leaves lost their turgidity after a few days. Later, these dropped off the branches and finally the saplings died. The vascular tissues in the outer layer of sapwood turned pink. After the death of the saplings the roots and the stem collar stained black.