13) 常綠臭椿 (福氏臭椿)
Ailanthus fordii Nooteboom
苦木科（Simaroubaceae）

英文名 (English name): Ailanthus

中國境內現狀：近危 (NT).
Status in China: Near Threatened (NT).

形態特徵：小喬木，高可達5米；小枝密被微柔毛。葉?羽狀複葉，聚生於枝端，長40-60厘米；小葉6-13對，對生或近對生，長圓狀卵形，長7-13厘米，寬4-6厘米，先端短漸尖，基部鈍圓形，偏斜，全緣。圓錐花序頂生，長20-40厘米。花單性或雜性；花萼杯狀，長約0.5毫米，具5鈍齒；花瓣5，長2-3毫米。雌花的花藥不發育，心皮5，花柱合生，柱頭5。翅果長3-5厘米，寬1-1.8厘米。

地理分布：鶴咀、歌賦山、沙田、馬鞍山、荔枝窩。雲南西雙版納地區。

生境與生態：生於丘陵和低山林中。

本種為稀有種，模式標本採自香港，首次約於1884至1886年在鶴咀發現，呈間斷分布於香港及雲南，具有科學研究價值，也具觀賞價值。多個生長地點位於郊野公園內而受到保護。本種受《林務規例》(香港法例第96章附例)保護。已成功進行人工繁殖，常用作行道樹和庭園綠化樹，城門標本林及香港多個市區的公園內有栽培。

Description: Small trees, up to 5 m tall; branchlets densely puberulent. Leaves odd-pinnate, crowded near apex of branches, 40-60 cm long; leaflets 6-13 pairs, opposite or nearly so, oblong-ovate, 7-13 cm long and 4-6 cm wide, apex shortly acuminate, base subrounded, asymmetrical, margin entire. Inflorescence terminal, paniculate, 20-40 cm long. Flowers unisexual or polygamous; calyx cup-shaped, ca. 0.5 mm long, 5-toothed; petals 5, 2-3 mm long. In female flowers anthers imperfectly developed; carpels 5; styles connate; stigma 5. Samara 3-5 cm long, 1-1.8 cm wide.

Distribution: Cape D'Aguilar, Mount Gough, Sha Tin, Ma On Shan, Lai Chi Wo. Xishuangbanna of Yunnan Province.

Habitat and Ecology: In lowland evergreen forest.

First discovered in Cape D'Aguilar in between 1884 and 1886, this rare species occurs exclusively and discontinuously in Hong Kong (the type locality) and southern Yunnan. It also has ornamental value. In Hong Kong many localities of occurrence are in Country Parks under adequate protection. The species has also been listed under the Forestry Regulations (Cap. 96 sub. leg.). It has been actively propagated and widely cultivated in Hong Kong as roadside trees and ornamental trees. Living specimens are planted in the Shing Mun Arboretum and a number of urban parks in Hong Kong.

參考文獻：(References)
Nooteboom,H.P., 1962: Flora Malesiana, Ser. 1, 6: 220. Kluwer Academic Publishers, Dordrecht.
Nooteboom, H.P., 1974: Ailanthus fordii Nooteboom, an endemic species of Hong Kong refound. Memoirs of the Hong Kong Natural History Society No.9: 16-17.
陳書坤，1997: 中國植物誌43：3。科學出版社，北京。