Wavyleaf Oak
Quercus × undulata
Family: Fagaceae
OTHER COMMON NAMES
Spanish: encinillo ondulata
CHARACTERISTICS
Wavyleaf oak is a naturally occurring cross between Q. gambelii and Q. turbinella, all native to Utah and the Intermountain West. It has a shrubby appearance, growing about 10 feet tall and wide. Thick, leathery leaves are a dark blue-green above and dull-green and hairy underneath. The leaves are toothed with wavy margins. In our region it will usually retain most of its leaves (though some leaf drop is nothing to be too concerned about). In colder places leaves will definitely drop.
LANDSCAPE USE
This plant is usually grown as a shrub, though it can be trained into a small tree. It makes a good screen.
GROWING CONDITIONS
AN EXPLANAITION OF TERMS USED
SUN in the low desert, afternoon shade from summer sun, can take full sun when mature and at higher elevations
WATER moderate
SOIL amended soil with good drainage
HARDINESS hardy to well below zero °F
BASIN terrace
CONTAINER not recommended
NUTRITION moderate
MAINTENANCE remove dead branches in spring
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
Oak acorns can often be made edible with blanching and other preparation methods but this isn’t the most edible of the species.
NATURAL DISTRIBUTION
Wavyleaf oak is a naturally occurring cross between Q. gambelii and Q. turbinella, all native to Utah and the Intermountain West.
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 undulata refers to the wavy margins of the leaves.
Toumey oak is most often a large shrub. Photo by arborsam, iNaturalist
Foliage detail, photo by Curren Frasch, iNaturalist
Flowers usually occur in April or May, photo by Sue Carnahan, SEINET
Acorns follow the flowers and ripen late summer into fall. Photo by Steve Ganley, iNaturalist