Zanthoxylum arborescens Rose

Zanthoxylum arborescens Rose, Contr. U. S. Nat
Herb. 5 : 112. 1897.
Zanthoxylum peninmlare Brand. Zoe 5 : 249. 1908.
A tree 3-3.6 m. high; branches unarmed, or armed with few, short prickles ; young twigs, rachis of the leaves and branches of the panicles more or less densely hispidulous ; leaves odd-pinnate, 0.8-1.8 dm. long; leaflets 3-7, commonly 5, oblong-elliptic to ovate or somewhat obovate, 5-7.5 cm. long, 2.5-4 cm. broad, more or less inequilateral and cuneate at the base, acute or often obtusely short-acuminate at the apex, slightly crenulate, mostly above the middle, or entire, glabrate above, hispidulous especially on the veins beneath ; panicles terminal or sometimes also lateral and terminal on the branches ; staminate flowers : calyx small ; sepals 5, triangular to triangular-ovate ; petals 5, reflexed, narrowly ovate to ovate or elliptic, 2.5-3 mm. long, 1-1.2 mm. broad, greenish-yellow; stamens 5, a little longer than the petals ; pistillate flowers not seen ; gynoecium apparently 2or 3-carpellary; follicles solitary, oblong-ellipsoid to subglobose, 4.5-5.5 mm. long, the valves 3-4 mm. broad; seeds ellipsoid, 3.5-4.5 mm. long, 2.5-3.5 mm. broad, often somewhat pointed at both ends, black, shining.
Type locality : Vmala, Sinaloa.
Distribution : Lower California and Sinaloa.

Zanthoxylum arborescens là một loài thực vật có hoa trong họ Cửu lý hương. Loài này được Rose miêu tả khoa học đầu tiên năm 1897.