KAMAL A. MALIK
Toxicodendron altissimum Mill.
A large polygamous tree, upto 30 m high or more. Leaves large, 30-40 cm or more long. Leaflets upto 12 cm long, 2.5-4 cm broad, alternate, ovate-lanceolate, usually cordate at base, glabrous except the veins and midrib near the base, with 2-4 coarse teeth, each with a large gland beneath, margin almost entire. Petiolules 2-10 mm long; midrib prominent. Inflorescence panicle, 10-30 cm long. Bracts minute. Flowers c. 7.0 mm across. Calyx 5-lobed, unequal, sepals much smaller than petals, c. 1 mm long and 0.5 mm broad, valvate, joined at the base, margin serrulate, glabrous, ovate, acuminate. Petals spreading, c.3 x 1.5 mm, glabrous, hairy at the base. Staminate flower with 10 stamens, filaments c. 3 mm long, arising from the base of small 10- lobed disc; anthers 2-celled, dehiscing longitudinally. Pistillate flower: ovary deeply divided, ovule solitary in each cell. Fruit samara, 3.5-5 cm long, twisted at the top, light reddish brown.
Fl. Per.: May-June Fr. Per.: July-August.
Type: Description of Toxicodendron altissimum Miller in Miller Gard. Dict. no. 10. 1768. Type is based on a plant cultivated in Chelsea Physic garden, however, Dr. N.K.B. Robson has informed us that no such specimen is available in the General Herbarium (BM) or in Herb. Sloane. Hence the description is accepted here as the type.
Distribution: Native in China, cultivated in temperate and subtropical regions of the world and often naturalized.
In Pakistan it is cultivated as a roadside tree on hills.