Gambel Oak
Quercus gambelii

Family: Fagaceae

OTHER NAMES
oak brush, Rocky Mountain White Oak, Utah White Oak

CHARACTERISTICS
Deciduous tree—this plant reaches variable heights depending on conditions, sometimes just a small shrub, sometimes reaching 40-50’ or more. Flowers April-June. Acorns ripen in September. Nice fall color—oranges and yellows, sometimes red. In nature browsing and fires usually keep plants dwarf (the come back readily from fire, growing from the roots) and they can sucker to form colonies. In the low desert they don’t tend to get as large as they get in the mountains. But this species DOES grow very upright, unlike most other Arizona native oaks which are very bushy when younger.

LANDSCAPE USE
Landscape shrub or tree.

GROWING CONDITIONS
AN EXPLANAITION OF TERMS USED

SUN afternoon shade encouraged for plants in the low desert, upper elevation plants can take full to part sun or even light shade
WATER moderate
SOIL prefers good drainage, amendments encouraged
HARDINESS hardy to about -30°F
BASIN middle zone
CONTAINER does ok in container but will not attain full size
NUTRITION moderate
MAINTENANCE very little

Photo of very large Gambel oaks near Sedona, Arizona by kankisa_ne_tunal, iNaturalist
Quercus gambelii on SEINET

ECOLOGY
Flowers in spring with inconspicuous, wind-pollinated flowers. Acorns ripen in fall. Oaks are wildlife keystone species hosting a mind-boggling number of insects. This brings in a vast array of substrate-insectivorous birds (birds that spend their time on these trees eating the insects). The acorns are important food for many birds and mammals (and some species eaten by people). The trees also provide important habitat for many birds and mammals. Almost all the oaks host a multitude of moths and butterflies including the following species:

Mexican-M Hairstreak (Parrhasius moctezuma)

Arizona Sister (Adelpha eulalia)

Short-tailed Skipper (Zestusa dorus)

Arizona Dull Firetip (Apyrrothrix araxes ssp. arizonae)

Burgess’s Sleepy Duskywing (Erynnis brizo ssp. burgessi)

Clitus Duskywing (Erynnis juvenalis ssp. clitus)

Meridian duskywing (Erynnis meridianus ssp. meridianus)

Scudder's Duskywing (Erynnis scudderi)

Mournful Duskywing (Erynnis tristis)

Oaks also host a diversity of insects that cause growths called “galls”. Galls are protective nests for the larvae of various insects (mostly tiny stingless wasps) to develop protected from pests. The have a diversity of shapes from giant ball-like growths, to small growths, on leaves or young stems. These galls do not harm healthy trees. Emory oaks that grow in riparian zones and get really tall are a favorite nesting site for owls and other raptors.

Oaks attract numerous other insects which, in turn, attracts canopy-gleaning birds.

ETHNOBOTANY
This species is native within the ranges of many indigenous peoples who use the acorns as food, usually with some leaching—the acorns have a lot of tannins. The wood is used as fuelwood, for furniture, other building materials, toys, ceremonial items, and other household implements.

NATURAL DISTRIBUTION
Found in forests, generally in association with ponderosa pine at higher elevations from 4,000-10,000’ across the intermountain west to Wyoming and south into northern Mexico.

TAXONOMY AND NAME
This plant is in the family Fagaceae, the beech family. There are 627 accepted species in the genus Quercus widely distributed in the northern hemisphere.
The genus "Quercus" is from Latin, meaning "oak", and the species name “gambelii” is named for William Gambel (1821-1849) an assistant curator at the National Academy of Sciences.