Shorea obtusa

Shorea obtusa is a deciduous tree in the Dipterocarpaceae family. Its common names include teng and Taengwood Balau. It comes from mainland Southeast Asia, including Myanmar and Thailand. Its range also covers Cambodia, Laos and Vietnam. It grows in dry forests shaped by seasonal monsoon rains. It also occurs in open woodland and dry, degraded land. Useful Tropical Plants reports a 2011 Least Concern assessment.

Garden references give a height of about 66 feet [20 metres]. They list a spread of about 49 feet [15 metres]. Broader accounts give heights of 33–98 feet [10–30 metres]. Large trees may have a branch-free trunk reaching 49 feet [15 metres]. The trunk can measure about 2 feet [0.6 metres] across. The tree grows at a moderate rate and sheds its leaves. Yellow flowers hang in clusters. The seeds have wings, which growers clip before sowing.

This tree needs full sun and soil that drains well. It suits sandy or loamy ground, including poor, rocky sites. It also grows on lateritic soils and shale-derived ground. Acid to neutral soil suits it, including very acid soil. It accepts dry or moist conditions. Its home climate has clear wet and dry seasons. Dry spells there can last up to six months. It grows best with 49–79 inches of rain each year. It can also grow with less rain. PFAF lists USDA hardiness zones 10–12. The tree also grows where dry-season fires occur.

Its main value lies in its timber and resin. The wood is heavy, hard and durable, even around water. People use it for building and furniture. The heartwood darkens from brown to deep or reddish brown. Pale sapwood forms a narrow band around it. Interlocked grain and high resin content can make sawing hard. The bark contains much tannin and releases a yellowish resin. People use the resin to seal boats and baskets. They also use it to make torches.

Reported local remedies use resin for wounds, ulcers and dysentery. Bark has a reported use against malaria. These records describe uses, not proof of safe treatment. The sources list no known food uses or hazards. That does not establish safety for people or pets. Insects can damage seeds, and fresh seed has low viability. Growers remove damaged seeds and sow the rest without delay. They use shaded nursery beds for this early stage.