白頭樹檢視原始碼討論檢視歷史
白頭樹 |
中文學名:白頭樹 拉丁學名:Garuga forrestii W. W. Smith 界:植物界 門:被子葉植物門 綱:雙子葉植物綱 亞 綱:原始花被亞綱 目:芸香目 亞 目:芸香亞目 科:橄欖科 屬:嘉欖屬 種:白頭樹 |
白頭樹是一種落葉喬木,高10—25米,幼枝密被柔毛,老枝無毛,紫褐色,有縱條紋及明顯的葉痕。 [1]
白頭樹形態特徵
小葉近無柄,披針形至橢圓狀長圓形,頂端漸尖,基部圓形或闊楔形,具淺齒,有小托葉。最下一對小葉小,長約1厘米,常早落 ;中間一對長7—12厘米,寬2—4厘米,側脈10—16對;頂生小葉長5—7厘米,具柄,柄長約1.5厘米。圓錐花序側生和腋生,常多數聚集於近小枝頂部,長14—25(—35)厘米,多次分枝,花軸及分枝纖細,密被直立的柔毛。
花白色,長約3毫米,花托杯狀,外被絨毛;萼片近鑽形,長0.2厘米,兩面被毛;花瓣卵形,長約3毫米,外被絨毛;雄蕊近等長;子房無柄,球形,和花柱被疏柔毛,柱頭5淺裂。果序有許多不結實的線形花梗。
果近卵形,一側腫脹,橫切面多少呈鈍三角形,長0.7—1厘米,直徑0.6—0.8厘米,兩端尖,先端具喙而偏斜一側,基部有宿存的淺杯狀花萼。花期4月,果期5—11月。
Trees, 10-15(-20) m tall. Branchlets densely pubescent when young, glabrescent, purple-brown, longitudinally striped and conspicuously lenticellate. Leaflets 11-19, nearly without petiolules; blades lanceolate or elliptic-oblong, densely pubescent when young, glabrescent, base rounded or broadly cuneate, margin shallowly serrate, apex acuminate, lowest pairs small, ca. 1 cm, often early deciduous, middle pairs 7-12 × 2-4 cm, with lateral veins 10-16 pairs, terminal leaflet 5-7 cm, with petiolule ca. 15 mm. Panicles 14-25(-35) cm, axillary or lateral, usually crowded toward ends of branchlets, multibranched; rachis and branches slender, densely tomentose. Flowers white, ca. 3 mm; receptacle cup-shaped, abaxially tomentose. Sepals nearly subulate, ca. 2 mm, hairy on both surfaces. Petals ovate, ca. 3 mm, abaxially tomentose. Stamens nearly equal. Ovary sessile, globose; style sparsely pubescent; stigma shallowly 5-lobed. Infructescence with many linear pedicels without fruits. Drupe nearly ovoid, one side dilated, 7-10 × 6-8 mm, ± obtusely deltoid in cross section, attenuate at both ends, apex with a point, base with persistent shallowly cupular calyx. Fl. Apr, fr. May-Nov.
Garuga forrestii W. W. Smith in Not. Bot. Gard. Edinb. 13: 162. 1921; Hand. -Maza. Symb. Sin. 7:631. 1933, Kalkm. in Blumea 7 (2): 461, fig. 2. 1953; 雲南植物志1: 461, 圖版45: 10-14. 1977; 雲南種子植物名錄, 上冊826. 1984.——G. yunnanensis Hu in Bull. Fan Mem. Inst. Biol. Bot. ser. 7: 212. 1936.
白頭樹分布範圍
白頭樹主要分布於雲南、四川之金沙江谷地及雲南省之怒江、瀾滄江、紅河河谷。
標本分布
雲南: 昆明、祿勸、峨山、麗江、墨江、鳳慶、蒙自、建水、金平