Betula pendula scales. The foliage is a pale to medium green and turns yellow early in the autumn before the leaves fall. In mid-summer, the female catkins mature and the male catkins expand and release pollen, and wind pollination takes place. The small 1 to 2 mm winged seeds ripen in late summer on pendulous, cylindrical catkins long and broad. The seeds are very numerous and are separated by scales, and when ripe, the whole catkin disintegrates and the seeds are spread widely by the wind. Silver birch can easily be confused with the similar downy birch ("Betula pubescens"). Yet, downy birch
Fokienia Tuyên Quang, Yên Bái and Vĩnh Phú), west central Vietnam (provinces of Đắk Lắk, Gia Lai, Lâm Đồng), and west to northern Laos. The name derives from the old Romanised name of Fujian province, China, from where the first specimen was introduced to Europe, collected by Captain Hodgins in 1908. "Fokienia" is an evergreen tree, 25–30 m tall. It has greyish-brownish bark that peels off when the tree is young. On older trees, the bark presents longitudinal fissures and becomes aromatic. The leaves are arranged in flattened branchlet systems, with the branchlets in one plane. The leaves on adult trees