Log in

Editor's Picks

Michael Eason hiking in Anza-Borrego Desert State Park to observe Washingtonia filifera in situ
Currently at San Antonio Botanic Garden, Michael's work has...
Amy Byrne | Feb 15, 2023
An exhibition that beautifully depicts and locates oaks
Roderick Cameron | Feb 09, 2023
Burke Oak Collection at New York Botanical Garden
The Coleman and Susan Burke Oak Collection at The New York...
Todd Forrest | Feb 08, 2023

Plant Focus

Quercus xjackiana acorns
The hybrid of Q. alba and Q. bicolor

Allan Taylor

Member profile by Ryan Russell, first published in Oak News & Notes Vol. 17, No. 1 (Winter 2013)


Allan Taylor
Alan Taylor - Photo John Sooklaris

Allan Taylor is a proud, long-stand­ing member of the International Oak Society, having joined at the very beginning. He was elected to the IOS Board in 2009, and served as editor of Oak News & Notes from 2009–12. This was a gratifying experience because it kept him in touch with the direction of the Society and it gave him the opportunity to write articles about his interests as well as the interests of other members. Allan says that his time as a member of the IOS has been a “con­tinuous source of inspiration” and has put him and kept him in touch with others of similar interests. Allan received a Lifetime Service Award at the 7th Tri­ennial Conference in Bordeaux for his service to the Society.

A lifelong resident of Colorado, the only  extended amount of time he spent away from the Centennial State were the three years he spent in the military, and four years during his graduate study. Allan has traveled extensively throughout the United States, Canada, Mexico, Europe and the Far East, but despite enjoying these travels immensely, he always returns with a greater ap­preciation of what his home state has to offer.

Allan’s professional career was spent in academia, working as a linguist at the University of Colorado where he was a faculty member for more than thirty years. He specialized in the study of Native American languages formerly spoken throughout the Great Plains and Southwest of the United States. Study of these languages often took Allan to reservations in different western Ameri­can states, and his work there was al­ways enhanced by exploring local flora, which sometimes included oaks.

Allan first became interested in oaks over fifty years ago when he learned that Colorado is home to a couple of interesting populations of hybrid oaks. These hybrid popula­tions are made up of the native Rocky Mountain Oak, Quercus gambelii Nutt. and a few other oak species found in the Middle West and Southwest of the United States. Over the years, Allan has visited most of the parts of the state that are home to these hybrid populations. It has become a great source of pleasure for Allan to compare and document the morphologies of these hybrids. Since these hybrids draw from more than one genome, there are an infinite number of possible combinations in genetic makeup which guarantees that there is enormous variation between individu­als. These differences include all parts of the plant’s physiology: growth habit and rate, stature, bark type, type and structure of leaves, frost hardiness, drought tolerance, fruit morphology as well as traits such as deciduous or ev­ergreen habit, bloom time, presence of fall color and timing of leaf drop.

Quercus xundulata Dolores River
Quercus ×undulata 'Dolores River'

Allan’s favorite oaks belong to the complex known as Quercus ×undu­lata Torr. (syn. Q. ×pauciloba Rydb.), which is the result of hybridization of no less than seven oak species. Most individuals in this complex are more shrub-like than tree-like, but in this case he says “size does not matter!” Whether a low shrub or a medium sized tree, there is more than enough variety in this complex to keep a researcher busy for a lifetime. The morphological variation, combined with the consider­able frost hardiness and drought tolerance, make Q. ×undulata selections a very attractive landscape addition in most areas of his region where winters can be severe and summers hot and dry.

Quercus xundulata Dolores River
Quercus ×undulata 'Dolores River'

Over his many years of observing Q. ×undulata and its parent species, Allan has made around 60 selections. He is most interested in leaf shape and color and whether the plant has attractive fall color. Most individuals of the complex have lobed leaves, inherited from the Q. gambelii parent, but most of the lobes are pointed, likely inher­ited from Q. turbinella Greene which also happens to be evergreen. Hence, many Q. ×undulata have blue, holly-like evergreen leaves which are a very desirable trait for a region with very few broad-leaved evergreen plants. A number of Allan’s selections are now under evaluation at Heri­tage Seedlings, in Salem, Oregon. After the evalu­ation, many (at least 10) will be offered for sale through the nursery trade. Fellow IOS member Dirk Benoit also offers several of Allan’s selections in Europe through his Pavia Nursery in Deerlijk, Belgium. These selections should constitute a major contribution to the plant palette for areas with hot dry summers and cold dry winters. Al­lan is reluctant to name a favorite (“they’re all my favorites” he says), but if forced to choose he would pick a selection which he named ‘Dolores River’. This small tree, to 18' tall (5m), has wide blue, holly-like leaves and is likely an F2 hy­brid of Q. gambelii and Q. turbinella. Strongly favoring its Q. turbi­nella parent, it grows as a clump at 4,800' (1,463 m) as in the beautiful red-rock country of the Dolores River Canyon, in Montrose County Colorado, on the eastern edge of the Colorado Plateau. “This is truly a unique tree!” says Allan, “A once in a lifetime discovery.”

Quercus xundulata Dry Cimarron
'Dry Cimarron', Quercus ×undulata type, shrub, taken in NE New Mexico, Union County, not far from Kenton, Oklahoma

Having seen a few of the parent trees of Allan’s selections and now growing a couple myself in central Missouri, I can say that they are out­standing. Allan has a wealth of knowl­edge and a great eye when it comes to selecting attractive oaks. This publica­tion certainly benefited from his lead­ership and eye for detail and we hope that he can be coaxed out of “retire­ment” someday soon. 

Ryan Russell

Photographs by Allan Taylor unless noted.

Allan has kindly provided the photographs below of more of his selections for the web version of this article. 

Phantom Canyon
(Above and below) 'Phantom Canyon', Quercus ×undulata type, tree form, taken in Phantom Canyon, near Canyon City, Colorado
Phantom Canyon


Azul de Salina
'Azul de Salinas', Quercus ×undulata but close to Q. turbinella, taken near Mountain Air, New Mexico
Phantom Holly
'Phantom Holly', Quercus ×undulata type, tree form, taken in Phantom Canyon, near Canyon City, Colorado
Phantom Sprite
(Above and below) 'Phantom Sprite', an environmentally dwarfed Quercus ×undulata type, taken in Phantom Canyon, near Canyon City, Colorado.
Allan comments: "In the background of the picture below are other very short 'trees'. They have trunks as big as your wrist, but are only 3 feet tall. I attribute their low stature to browsing by livestock and/or deer."
Phantom Sprite
'Rimrock', Quercus ×undulata  type very close morphologically to Q. grisea; taken in Phantom Canyon, near Canyon City, Colorado
'Tinnie', a Quercus ×undulata type, very large shrub/small tree, hybrid including (probably) Q. gambelii, Q. grisea, and Q. oblongifolia; taken just north of the village of Tinnie, in Lincoln County, New Mexico
Erick the Red
'Erick the Red'. Hybrid tree (actually a clump of trees, not evident because the leaves hide the several trunks), cross between Quecus stellata and Q. havardii, taken near Erick, Oklahoma