Quercus jonesii Trel.

Mexico (San Luis Potosi, Chihuahua, Durango, Aguascalientes, Guanajuato, Nuevo Leon, Sinaloa, Sonora) ; 600 - 2880 m ;

usually 6 m, sometimes to 10-15 m, with trunk 8-40 cm in diameter; rounded crown;

7-14 cm long, 6-12 wide; broadly oboval, oval or suborbicular; thick, leathery; adaxial surface smooth ; apex rounded sometimes acute and aristate; base cordate, auricled; margin thick, more or less revolute, entire, or sometimes with 1-5 pairs of bristle-tipped teeth; green above, slightly lustrous, with some short fascicled hairs, sessile or not, mainly along midrib and base, and sometimes golden uniseriate glandular hairs; paler beneath, yellowish, with scattered golden glandular hairs and stipitate fascicled hairs at axils, sometimes almost glabrous except axil tufts; 6-10 straight vein pairs, sometimes impressed adaxially; epidemis papillose; petiole 0.8-1.2 mm long, becoming glabrous;

male catkins 7-12 cm long, with around 13 flowers; pistillate flowers singly or paired, on 1 cm long rachis;

acorn 8-10 mm long, 5-8 mm in diameter; stalkless or on a 5 mm long peduncle, solitary or 2-4 clustered at tip of branches; enclosed 1/3 or 1/2 by cup; maturing in 1 year;

not hardy; prefers wet places;

– A. Camus : n° 179; – Sub-genus Quercus, section Lobatae, Series Erythromexicanae, Group Aristatae; – For Govaerts & Frodin, 1998, and for S. Valencia-A., 2006, Q.aerea is a true species in Mexixo (Chihuahua), with small, ovoid-rounded buds, and with leaves “old golden bronze” couloured beneath, because of wax. – For some Authors, the name of this taxon is coccolobifolia , and jonesii is a synonym…. – Resembles Q. radiata which is reticulate adaxially, has a greater number of clustered acorns (to 8 or more) and abaxially with fascicled stipitate hairs on the whole surface of the blade.