Magnolia kobus, known as mokryeon, kobus magnolia,or kobushi magnolia,is a species of Magnolia native to Japan (Kyushu, Honshu, and Hokkaido) and Korea and occasionally cultivated in temperate areas. It is a deciduous, small to tall tree which has a slow rate of growth but can reach 8–15 m (25–50 ft) in height and up to 10 m (35 ft) in spread.

Classification
Two varieties of Magnolia kobus are recognized by some sources, such as Hortus Third,with var. borealis being a tree to 25 m (75 ft) high, with leaves to 15 cm (6 in) long, and var. kobus, a tree to 10 m (30 ft) high, with leaves to 10 cm (4 in) long.

Magnolia kobus is classified within Magnolia subgenus Yulania.

The kobus magnolia is closely related to the star magnolia (Magnolia stellata), and some authorities consider the star magnolia to be a variety of M. kobus, M. kobus var. stellata.

Description
Magnolia kobus blooms in the early spring, bearing pleasantly fragrant white flowers with hints of pale pink about 10 cm (4 in) in diameter. The flowers are produced before the leaves, as with most members of Magnolia subgenus Yulania. Young trees do not flower.

The summer foliage of the kobus magnolia is dark green. Leaves have an obovate shape with a pointed tip, a smooth, or glabrous, leaf underside, and smooth, even edges. Leaves are 8–15 cm (3–6 in) long, in an alternating arrangement. In autumn, the leaves take on a yellow color and drop from the tree.

Older bark, such as that of the trunk, is grey-brown, while new stems are green with small brown spots. There is a strong odor to broken branches or twigs.

A seed estimated to be 2,000 years old was found in a pit in the ancient bronze-age village of Asada. The archaeologists planted the seed thinking that surely it wouldn't grow but they were wrong. Unlike the other Magnolia trees it had 7 or 8 petals on its blossoms rather than six.
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