............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ 旱冬瓜旱冬瓜(AlnusnepalensisD.Don),又名蒙自榿木(中國(guó)樹木分類學(xué)),尼泊爾榿木(中國(guó)植物志),冬瓜樹(云南),為樺木科榿木屬大喬木,高約18米,胸徑1米;小樹樹皮光滑綠色,老樹樹皮黑色粗糙縱裂;枝條無(wú)毛,幼枝有時(shí)疏被黃柔毛;芽具柄,芽鱗2枚,光滑。葉紙質(zhì),卵形、橢圓形,長(zhǎng)10-16厘米,頂端漸尖或驟尖,稀鈍圓,基部寬楔形,稀近圓形,邊緣具疏齒或全緣,葉面翠綠,光滑無(wú)毛,背面灰綠,密生腺點(diǎn),幼時(shí)疏被棕色柔毛,沿中脈較密,或多或少宿存,脈腋間具黃色髯毛,側(cè)脈12-16對(duì);葉柄粗壯,長(zhǎng)1.5-2.5厘米,近無(wú)毛。雄花序多數(shù)組成圓錐花序,下垂。果序長(zhǎng)圓形,長(zhǎng)約2厘米,直徑約8毫米,序梗短,長(zhǎng)2-3厘米,由多數(shù)組成頂生,直立圓錐狀大果序;果苞木質(zhì),宿存,長(zhǎng)約4毫米,頂端圓,具5淺裂。果為小堅(jiān)果,長(zhǎng)圓形,長(zhǎng)約2毫米,翅膜質(zhì),寬為果的1/2,稀與果等寬。