English Oak, Truffle Oak,
Pedunculate Oak
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Quercus robur
Family: Fagaceae
Habit: Large, open headed shade tree with an initially
rounded or pyramidal crown becoming broad and rounded at maturity.
Hardiness: Zone 4 to 8
Leaves: Alternate, simple, 2 to 5” long and ¾” to 2 ½” wide, with 6 to 14
shallow, rounded lobes. English Oak leaves are thick and glossy. They are dark
green to almost blue-green above with a pale blue-green underside in the summer.
They sometimes drop when still green but usually turn yellow/brown late in the
fall and hang on into winter.
Bark: Dark green or brown and smooth when young, changing to brown and
then a deeply furrowed dark gray at maturity.
Flowers: Males produce a yellow-green catkin in the spring.
Fruit: Acorns are ½” wide and 1” long. They occur singly or in clusters
of up to five and ripen the first year (English oaks are in the White oak
group). They are a shiny brown color, usually enclosed about 1/3 by their cap.
Landscape Value: This tree adapts well to most soil types and is
relatively pest free. Plant in full sun, allow plenty of space for growth, and
prune for structure often when young. English Oaks provide dense summer shade.
When considering placement in the landscape, remember that the brown leaves
often persist through the winter creating an ice/snow shadow on the north side
of the tree. Don’t plant on the south side of a building, street, driveway or
parking lot. This tree is considered drought tolerant once established but is
not as xeric as Bur or Gambel oak.
How It Will Do in Colorado: Several English Oaks in Europe are
believed to be more than 1,000 years old. It is a large shade tree at maturity
with a massive trunk and branches. It is an underused tree along the Front Range
mainly due to its lack of fall color. There are several fine examples of mature
English Oaks at Fairmount Cemetery in Denver.
Cultivars: More than 100 cultivars have been introduced. The most
common is ‘Fastigiata,’ or Columnar English Oak which grows only 15’ wide by
50-60’ tall.
Information Sources:
Dirr, Michael Dr., Manual of Woody Landscape
Plants, 5th Ed., 1998
University of Connecticut Plant Database
Photos - David Flaig, City of Littleton
Photos - University of Connecticut Plant Database