22 MISC. PUBLICATION 101, U. S. DEPT. OF AGRICULTURE 
Mexican oak, a small tree or shrub, as having value for goats in 
southern New Mexico, but its importance is derived more from 
abundance and distribution than from exceptional palatability. 
Utah oak, a large shrub or small tree, is ordinarily a fair browse 
on dry chaparral-covered hills and slopes, especially over limestone, 
between about 4,000 and 9,000 feet in Utah, southern Wyoming, 
Colorado, and northern Arizona and New Mexico. Excessive eat- 
ing of the acorns, however, has caused losses from bloat among 
sheep in Utah. Vreeland oak, a small shrub not over 5 feet high, 
is abundant on dry slopes and loamy bench lands, chiefly of the 
yellow pine type, in southwestern Colorado and northern New 
Mexico, and provides considerable fair browse, especially in spring 
and fall, on certain ranges; its acorns are freely taken by all classes 
of stock in the fall. 
Arizona white oak (@Q. arizonica), or Arizona oak, a medium- 
sized tree, is (with the possible exception of gray oak, Q. grisea) 
the commonest live oak in southern New Mexico and Arizona and 
adjacent Mexico, being abundant in rocky foothills and canyons 
of the pifion-juniper belt up to subalpine elevations. Its palatabil- 
ity to goats, cattle, and sheep is fair and, because of its quantity 
and availability in late fall, winter, and early spring, it is locally 
one of the more important browse species. 
Gray oak (Q. grisea), one of the commonest Southwestern live 
oaks, occurs both as a shrub and a tree in the region from Arizona 
to western Texas. The thickish, gray-green, or somewhat bluish 
leaves persist until the following spring. It is typical of the wood- 
land type, or pifon-juniper belt, and is often the most abundant oak 
in its range, frequently growing in thick clumps. This member 
of the white oak group is in a number of places the most important 
local browse species. Analysis of the leaves and younger twigs, as 
made by the Bureau of Chemistry and Soils, is as follows: 
Per cent 
VE OTS CUT eo aE I a etn pe 5. 94 
AS The oS es es es eo ee ea 3. 30 
ft] 80 Sol ean S| As KG) ea ec ARE a cette ae peo ihe i Nee eh gt 2.61 
Proteins ies! 72t 8h Ski AE eae ode 9.13 
Crude; fibemse 4. bi 6. seyytey haha WE Es Ret eae 7A Gs 
Nitrogen-free, extract.24.-4. 4) ot ee ee 51.91 
100. 00 
While high in crude fiber this species is fairly comparable to 
alfalfa hay both in nitrates (protein) and in carbohydrates (nitro- 
gen-free extract), but rather low in fats (ether extract). It fur- 
nishes, therefore, a good body-building and energy-sustaining browse 
but with considerable roughage and rather inferior fattening qual- 
ities. The species is high in tannin content, and perhaps has poten- 
tial utility for tanning. 
California scrub oak (Q. duwmosa), because of its abundance as 
chaparral on dry foothills and slopes and its typically low habit 
(rarely a small tree), is often a fairly important sheep and goat 
browse but is distinctly inferior on cattle range. Mackie’s (79) 
analyses of the leaves of six native California oaks show that this 
species has a much higher amount of tannin than the other five, 
the percentage being 14.06 on an air-dry basis. Apparently, ewes 
