Feature Tree: September 2001
Turkish Filbert
Common Name: Turkish
Filbert
Scientific Name: Corylus
colurna
Family: Betulaceae
This Tree in Colorado: These
trees deal well with temperature extremes (zone 4), snowstorms and windstorms.
Both the form and leaf shape closely resemble that of a littleleaf linden and
therefore this tree makes an excellent substitute when a formal, medium sized,
pyramidal tree is desired. Boulder has a nice row of established Turkish
filberts and the current state champion (14” DBH). Their forestry staff plants
several additional trees each year and has been impressed at how it has
performed as a street tree.
Habit: Has
a densely pyramidal form when younger, very similar to that of a littleleaf
linden. It is pyramidal-oval to almost round at maturity. Considered a medium
sized shade tree, the mature size is approximately 40-50 feet in height with a
20-30 foot spread.
Landscape Value: The
tree is somewhat difficult to transplant and must receive supplemental watering
for the first few summers. Once established it is quite drought tolerant. It is
able to withstand somewhat alkaline soils but doesn’t like heavy clay soils
that remain saturated.
Fruit: The filbert nuts develop inside an unusual bract that is actually a modified leaf.
Leaves: The attractive dark green summer foliage resembles that of a linden from a distance. The fall color is usually just a yellow-brown but a nice yellow color occurs periodically.
Bark:
The bark becomes flaky with age and as scales fall off a brown or orange-brown
bark is exposed.
Insects and Diseases: The tree seems to be free from insect or disease problems. Even the aphids tend to feed elsewhere. When other species such as maples and lindens display scorch symptoms, the Turkish filberts remain green and vigorous.
Information Sources:
Dirr, Michael Dr., "Manual of Woody Landscape Plants," 1990
Michigan State University Extension
Colorado State University Extension