850 TREES OF NORTH AMERICA 



with the wing longer or shorter than the body, and sometimes only about f ' long and T ^ ' 

 wide, with the wing longer or not more than half the length of the body. 



A tree, usually 20-30 high, with a trunk 6'-8' in diameter, and ashy gray branchlets 

 pale pubescent when they first appear, becoming glabrous or puberulous during their second 

 season. 



Distribution. Mountain canons at altitudes of 5000-600(); in Arizona more common 

 than F. velutina; less abundant in southern New Mexico; in Sonora. 



Often used to shade the streets in the towns of southern Arizona. 



15. Fraxinus oregona Nutt. 



Leaves 5'-14' long, with a stout grooved and angled pubescent, tomentose or glabrous 

 petiole, and usually 5-7, rarely 3, or on young trees occasionally 9, ovate to elliptic or rarely 

 oval or obovate leaflets usually contracted at apex into a short broad point, gradually nar- 



Fig. 754 



rowed at base, and entire or remotely and obscurely serrate, usually coated below and on 

 the petioles with thick pale tomentum when they unfold and pubescent above, or nearly 

 glabrous or pilose with a few scattered hairs, and at maturity light green on the upper sur- 

 face, paler and usually tomentose, puberulous or rarely glabrous (var. glabra Rehd.), on 

 the lower surface, 3'-7' long and I'-lf ' wide, with a broad pale midrib, conspicuous veins 

 arcuate near the margins, and reticulate veinlets, the lateral usually sessile, rarely on petio- 

 lules up to \' , or that of the terminal leaflet up to 1 ' in length ; turning yellow or russet 

 brown in the autumn before falling. Flowers dioecious, appearing in April or May when 

 the leaves begin to unfold, in compact glabrous panicles covered in the bud by broad- 

 ovate scales coated with rufous pubescence; staminate flower composed of a minute calyx, 

 short filaments, and short-oblong apiculate anthers; calyx of the pistillate flower lacini- 

 ately cut and shorter than the ovary narrowed into a stout style divided into long conspic- 

 uous stigmatic lobes. Fruit in ample crowded clusters, oblong, obovate to oblanceolate 

 or elliptic, rounded and often emarginate or acute at apex, 1/-2' long and \'-\' wide, the 

 wing decurrent to the middle or nearly to the attenuate base of the clavate or ellipsoid 

 slightly compressed many-rayed body. 



A tree, frequently 70-80 high, with a long trunk occasionally 4 in diameter, stout 

 branches forming a narrow upright head or a broad shapely crown, and thick terete branch- 

 lets more or less densely coated with pale or rarely rufous silky pilose tomentum per- 

 sistent during their second year or occasionally deciduous during their first summer, be- 

 coming light red-brown or orange color, glabrous or puberulous, often covered with a 

 slight glaucous bloom, marked by small remote pale lenticels, and during their first and 



