WOOTON AND STANDLEY—FLORA OF NEW MEXICO, 165 
There are several well-marked groups of closely-related species, the most conspicuous 
of which is that clustered about Q. gambelii, including Q. utahensis, Q. submollis, Q. 
gunnisonii, Q. vreelandu, Q. novomericana, and Q. leptophylla, all of which have 
green deciduous leaves of much the same texture and outline with varying degrees of 
pubescence. Another group is that consisting of shrubs of small or large size (never 
forming trees) of the higher mountains, having more or less persistent blue green 
leaves—Q. undulata, Q. fendleri, Q. rydbergiana. Yet another well-marked group 
contains the low trees of the southern part of the State, occurring among the rocks 
and canyons of the drier and hotter mountains. These are Q. grisea, Q. arizonica, and 
Q. reticulata, the last being a large tree in the mountains of New Mexico. A single 
chestnut oak, known from two stations, is Q. muhlenbergii, a most unexpected find. 
The affiliations of the other species are not so easily seen, each species standing 
more or less by itself in New Mexico. 
Acorns of the different oaks were formerly used by the Indians as food. They were 
boiled or roasted or sometimes dried and ground into flour. 
KEY TO THE SPECIES. 
Acorns sericeous-tomentose inside, maturing the second year.... 1. Q. hypoleuca. 
Acorns not sericeous-tomentose inside, maturing the first year. 
Leaves bluish, grayish, or yellowish green (never bright 
chlorophyll green), more or less coriaceous, mostly 
persisting until the appearance of new leaves, hence 
the plant leafy all the time. 
Leaves not persisting; medium-sized shrub............ 2. Q. fendleri. 
Old leaves persisting till after the appearance of the 
young ones; shrubs or trees. 
Mature plants shrubs, never trees. . 
Plant about 1 meter high, with very small 
acorns and leaves............------------ 4. Q. rydbergiana. 
Plants more than a meter high, the leaves and 
acorns large. 
Leaves fulvous beneath; cup turbinate.... 6. Q. turbinella. 
Leaves not fulvous beneath; cup hemis- 
pheric. 
Leaves only moderately coriaceous, 
erisped..............---------- 3. Q. undulata. 
Leaves strongly coriaceous, much 
crisped and spinulose-toothed. . . 
Mature plants trees (shrubby forms immature, 
usually not fruiting). 
Scales of the cup thin, only slightly corky- 
thickened on the back; mature leaves 
yellowish green. 
Leaves of the same color on both surfaces... 7. Q. emoryi. 
Leaves fulvous beneath, especially when 
young.............2.-2-22--2.----- 8. Q. wilcoxit. 
Scales of the cup corky-thickened on the back; 
leaves fulvous beneath, glabrate above. 
Acorns large; mature leaves all more or less 
conspicuously toothed (resembling 
those of Q. fendleri). ..........0.2-2-- 9. Q. confusa. 
on 
a) 
. pungens, 
