TREES AND SHRUBS. 



PTEROCARYA REHDERIANA, C. K. Schneid. 



(Pterocarya fraxinifolia X stenoptera.) 



Pterocarta Rehderiana (stenoptera X fraxinifolia), C. K. Schneider, III. Ilandb. Laubholzk. 



i. 93 (1904). 

 Pterocarya stenoptera, Render, Bailey Cycl. Am. Hort. hi. f. 3013 (not C. De Candolle) 



(1901). 

 Pterocarya fraxinifolia x stenoptera, Render, Mitt. Deutsch. Dendr. Ges. xii. 116 (1903). 



Leaves imparipinnate, from 25 to 35 centimetres long, with puberulous petioles from 4 to 5 

 centimetres in length ; rhachis sparingly glandular and hairy or nearly glabrous, narrowly winged 

 between the upper leaflets, particularly on vigorous branches ; leaflets from eleven to twenty-one, 

 sessile, narrow-oblong to oblong-lanceolate, acute or acuminate, very oblique at the base, crenate- 

 serrate, with glandular-tipped teeth, glabrous, dark yellowish green on the upper surface, lighter 

 green on the lower surface, sparingly pubescent while young, at maturity glabrous with the excep- 

 tion of the axillary tufts of brown hairs, from 6 to 14 centimetres long, the lower ones the smallest, 

 the terminal leaflet slender-petioluled, oblong-obovate, cuneate at the base. Flowers monoecious ; 

 staminate flowers in short-peduncled or nearly sessile catkins from 5 to 7 centimetres in length 

 and originating from lateral axillary naked buds near the ends of the branchlets of the previous 

 year ; flowers sessile, glandular, and sparingly villous ; the bract and the two bractlets connate, 

 free at the apex, the upper sepal always conspicuous, the lower sepals often minute or wanting ; 

 stamens from eight to ten, with very short filaments and oval-oblong anthers ; pistillate flowers 

 in many-flowered slender pendulous and long-stalked racemes from 15 to 20 centimetres in length 

 and terminal on the branchlets of the year ; flowers sessile, remote, each flower subtended by a 

 small subulate bract shorter than and adnate to the two lateral oval bractlets connate to the mid- 

 dle with the perianth; perianth divided above the middle into four lanceolate teeth exceeding the 

 bractlets, the whole covered with minute yellow glands ; style with two oblong-ovate recurved 

 stigmata. Fruit winged, subglobose, with a conical apex, about 1 centimetre long, the wings 

 spreading, elliptic to oblong-ovate, from 10 to 15 millimetres long and from 6 to 7 millimetres 

 broad. 



A tree, usually with several ascending stems, covered with light gray bark divided by shallow 

 longitudinal fissures into narrow ridges broken into small thin plates, and branchlets glandular 

 and slightly villous while young, soon glabrous, becoming greenish brown during the first season 

 and brown and lustrous in their second year. Winter-buds naked, the axillary usually superposed 

 in pairs ; the upper one long-stalked. Flowers proterandrous, appearing in May with the leaves. 

 Fruits ripen in September. Leaves fall without change of color after the first frost. 



There is little doubt that this handsome tree is a hybrid between Pterocarya fraxinifolia, Spach, and Pterocarya 

 stenoptera, C. De Candolle. It originated from seeds of Pterocarya stenoptera, and in all its characters it is interme- 

 diate between the two species. From Pterocarya fraxinifolia it chiefly differs in its narrowly winged rhachis usually 

 sparingly villous while young, the narrower less distinctly acuminate leaflets, and the narrower and longer wings of the 

 fruits ; from Pterocarya stenoptera it differs in its more coarsely serrate acute and larger leaflets, with the axils of the 

 veins bearded beneath, in the narrow, not serrate, wings of the rhachis, the wings being usually absent between the lower 

 leaflets, and in the shorter and broader wings of the fruits. 



The trees of Pterocarya Rehderiana at the Arnold Arboretum were raised from seeds received in 1879 and 1880 



