San Francisco Botanical Garden

Common name: Dawson’s magnolia (English)

Family: Magnoliaceae (Magnolia)

Synonym: Yulania dawsoniana

Distribution: China

IUCN Red list: Endangered

Life form: Deciduous tree

Flower color: Whitish inside, reddish outside

Flowering Time at SFBG: March

Height: 20 m

Magnificent Magnolia Facts: Magnolia dawsoniana was first introduced to the West in 1908 and named after Jackson T. Dawson, the first superintendent of Harvard University's Arnold Arboretum. This rare species is native to the mountains of Hunan, Sichuan, and Yunnan provinces in China, where it grows at elevations of 1,400-2,500 m. Magnolia dawsoniana is considered an endangered species by the IUCN Red List due to intensive logging and its population is severely fragmented throughout the provinces where it occurs. With a remaining forested area of approximately 200 km², "there is a continuing decline in the extent of forest cover and the habitat quality for this species," according to the IUCN Red List report.

Growing Conditions: Direct sun or partial shade; prefers well-drained soil and has average water needs. Has low drought tolerance and low flood tolerance.

Botanical Description: Trees, to 20 m tall, to 1 m d.b.h. Twigs yellowish green becoming yellowish brown, glabrous or with fine trichomes, sparsely lenticellate. Petiole slender, 1-3 cm, base with short stipular scar; leaf blade obovate to elliptic-obovate, 7.5-14(-18) × 4-8 cm, basal ca. 2/3 gradually narrowing, abaxially pale green, vein axils and both sides of midvein usually residual with white villous hairs, adaxially green and glossy with only fine trichomes along midvein but glabrescent, secondary veins 8-10 on each side of midvein and usually reddish, reticulate veins conspicuously prominent on both surfaces when dry, base cuneate and usually oblique, apex obtuse, shortly acute, or rarely emarginate. Peduncle 1-1.5 cm, nodes villous. Flowers appearing before leaves, 16-25 cm in diam., erect to nodding, fragrant. Tepals 9-12, white but outside reddish, narrowly oblong-spoon-shaped to obovate-oblong, subequal, apex obtuse to emarginate. Stamens purplish red, 1.2-2 cm; filaments 3-4.5 mm. Gynoecium narrowly cylindric, 1.5-2 cm. Fruit dark red when fresh turning dark reddish brown, cylindric, 7-14 × 2.5-3.5 cm, slightly curved because part of carpels sterile; mature carpels obovoid, with sparse yellow lenticels, 2-valved, apex rounded and without a beak. Seeds compressed orbicular or irregularly triangular, ca. 1 cm in diam. (Flora of China)