by Eric Hammond, James Klett, and Alison S. O’Connor* (9/20)
- Trees provide shade, beauty, and protection from harsh winter winds.
- Columnar and fastigiate tree forms provide the benefits of larger trees, and can fit into smaller landscapes.
- Trees with narrower forms can be evergreen or deciduous.
- Often, columnar trees can be used to make a statement and provide interesting forms and textures.
Everyone enjoys the beauty of shade trees, but many Colorado landscapes are too small to accommodate large trees. Narrow, columnar, and fastigiate trees are great options to enjoy the beauty and environmental benefits of trees and fit into smaller spaces.
How to Select Columnar and Fastigiate Trees
The terms “columnar” and “fastigiate” are generally used interchangeably.
These trees are more narrow than wide, with a ratio of height to width of 5-to-1 or greater. These species have varied forms and shapes, from stovepipe to light pole appearances. Species can have interesting forms, textures, shapes, fall color, fruit, flowers, and bark. There are also trees with pendulous forms that grow upright but have some drooping or weeping branches.
Many columnar selections have been made from naturally occurring narrow species. These selections are propagated asexually through grafting
and cuttings. The narrow form of trees is most pronounced when trees are
young; as they mature, the form may widen.
Select a tree species with a mature size that fits your available space. Check for obstructions from buildings or fences and overhead utility lines. Be sure to plant for the mature height and width of the tree (refer to Table 1).
https://cmg.extension.colostate.edu/Gardennotes/636.pdfWhen planting, dig a saucer-shaped hole approximately three times the
width of the root ball. The root flare should be visible following planting and slightly above grade. Ensure the large structural roots are at soil grade. For detailed planting instructions, refer to CSU Extension Garden Note #636 “Tree Planting Steps”.
Species vary in water requirements and this needs to be accounted for during the tree selection process. Plant trees with higher water needs in areas that can be easily irrigated during periods of drought. Do not plant trees that have low-water needs in heavily irrigated lawn areas or at the base of slopes. Water is paramount to overall tree health and establishment. Though trees are narrower in shape, it doesn’t mean they are drought resistant (unless stated).
Culture and Maintenance
All trees will benefit from regular water during establishment. It is
recommended that wood mulch be used at the base of trees, instead of
plant material (including turf) or rocks. Wood mulch has been found to be
beneficial to tree growth and health and doesn’t compete with the tree for
Pruning for narrow trees is undertaken mainly to correct structural defects, like co-dominant trunks or to remove lower branches. Ideally, pruning should be done in the late winter or early spring, prior to budbreak.
Columnar Trees and Storm Damage
Columnar trees are often more prone to storm damage. This is especially true for fast growing species and those that have narrow branch angles and codominant trunks. Slower growing species and those with shorter and more horizontal branching are less likely to be damaged with heavy snows and wind.
Description of Table 1
Table 1 has a list of both columnar evergreen and deciduous trees for Colorado landscapes. The table includes the species name, mature size (H x W), growth rate, soil moisture needs, and aesthetic value and cultural hints. this list is not comprehensive, as new cultivars are introduced into the nursery trade and others replaced. Some of these species may not be as readily available as others. Contact your local garden centers and nurseries for availability.
Table 1. Columnar and Fastigiate Trees for Colorado
|Genus||Species||Cultivar||Common Name||Mature Size (HxW)||Water Use||Aesthetic Value and Cultural Hints|
|Acer||platanoides||‘Crimson Sentry’||Crimson Sentry Norway maple||30 x 15||Med-High||Red-purple summer foliage; leaves more scorch resistant|
|Acer||platanoides||‘Columnare’||Columnar Norway maple||50 x 20||Med||Yellow flowers in early spring; dense canopy|
|Carpinus||betulus||‘Frans Fontaine’||Frans Fontaine hornbeam||25 x15||Med||Interesting bark; one of the more narrow hornbeams; yellow fall color|
|Celtis||occidentalis||‘JFS-KSU1’||Prairie Sentinel® hackberry||45 x 12||Low-Med||Drought and heat tolerant; leaves susceptible to nipple gall; yellow fall color|
|Ginkgo||biloba||‘Princeton Sentry’||Princeton Sentry ginkgo||40 x 15||Med||Tolerant to urban conditions once established; seedless male cultivar; yellow fall color|
|Juniperus||chinensis||‘Blue Point’||Blue Point juniper||12 x 6||Low||Dense blue-green foliage|
|Juniperus||chinensis||‘Hetzi Columnaris’||Hetzi Columnar juniper||15 x 5||Low||Bright green foliage; dusty-blue fruit|
|Juniperus||chinensis||‘Spartan’||Spartan juniper||18 x 5||Low||Rich green foliage|
|Juniperus||chinensis||‘Spearmint’||Spearmint juniper||12 x 5||Low||Bright green foliage|
|Juniperus||scopulorum||Rocky Mountain juniper||20 x 15||Low||Drought tolerant;|
|Juniperus||scopulorum||‘Blue Arrow’||Blue Arrow juniper||20 x 5||Low||Bright blue foliage|
|Juniperus||scopulorum||‘Cologreen’||Cologreen juniper||15 x 8||Low||Green foliage|
|Juniperus||scopulorum||‘Gray Gleam’||Gray Gleam juniper||15 x 8||Low||Male cultivar (no fruit); silvery-gray color|
|Juniperus||scopulorum||‘Medora’||Medora juniper||12 x 6||Low||Male cultivar; blue-green foliage|
|Juniperus||scopulorum||‘Moonglow’||Moonglow juniper||15 x 8||Low||Blue-gray foliage|
|Juniperus||scopulorum||‘Skyrocket’||Skyrocket juniper||18 x 3||Low||Male cultivar; very narrow form; silvery-blue foliage|
|Juniperus||scopulorum||‘Wichita Blue’||Wichita Blue juniper||18 x 5||Low||Male cultivar; light silvery-blue foliage|
|Juniperus||scopulorum||‘Woodward’||Woodward juniper||18 x 4||Low||Plant Select® recommendation; resistant to snow load breakage; blue-green foliage|
|Juniperus||virginiana||‘Taylor’||Taylor redcedar||15 x 4||Low||Believed to be a male cultivar; soft silvery blue-green foliage|
|Malus||x||‘Red Baron’||Red Baron crabapple||20 x 4||Low-Med||Reddish-purple foliage in the spring turning to bronze-green; dark red fruit and flowers|
|Malus||x||‘Adirondack’||Adirondack crabapple||18 x 10||Low-Med||Floriferous white blooms|
|Picea||abies||‘Cupressina’||Columnar Norway spruce||18 x 4||Med||Short dark green needles; large cones; sheds heavy wet snow|
|Picea||glauca||‘Pendula’||Weeping White spruce||20 x 6||Low-Med||Weeping branches with an upright habit; rich blue-green needle color|
|Picea||glauca||‘North Star’||North Star white spruce||15 x 7||Low-Med||Shorter height; dense, dark green needles|
|Picea||pungens||‘Baby Blue Eyes’||Baby Blue Eyes spruce||15 x 8||Med||Smaller than most spruce; baby blue needle color|
|Picea||pungens||‘Bakeri’||Bakeri blue spruce||30 x 15||Med||Silvery-blue needles|
|Picea||pungens||‘Fastigiata’||Columnar blue spruce||25 x 10||Med||Striking blue needle color|
|Picea||pungens||‘Hoopsii’||Hoops blue spruce||35 x 18||Med||Very blue needle color|
|Picea||pungens||‘Blue Totem’||Blue Totem blue spruce||18 x 9||Med||Sharp angled branches; very blue color|
|Pinus||heldreichii||Bosnian pine||20 x 10||Low||Stiff, dark green needles; salt tolerant|
|Pinus||heldreichii||‘Compact Gem’||Compact Gem Bosnian pine||12 x 6||Low||Stiff, very dark green needles; slow growing|
|Pinus||heldreichii||‘Emerald Arrow’||Emerald Arrow Bosnian pine||20 x 8||Low||Upright selection of Bosnian pine; bark is silvery|
|Pinus||heldreichii||‘Satelit’||Satelit Bosnian pine||20 x 8||Low||Upright selection of Bosnian pine|
|Pinus||mugo||‘Columnaris’||Columnar mugo pine||20 x 10||Low-Med||Shorter in height; emerald green foliage|
|Pinus||mugo||‘Fastigiata’||Upright mugo Pie||15 x 4||Low-Med||Narrower uprght habbit|
|Pinus||mugo||‘Tannenbaum’||Tannenbaum mugo pine||30 x 18||Low-Med||Compact pyramidal form; good winter color|
|Pinus||nigra||‘Arnold Sentinel’||Arnold Sentinel Austrian pine||15 x 8||Low-Med||Narrower version of Austrian pine; prone to storm breakage due to longer needles|
|Pinus||nigra||‘Komet’||Komet Columnar Austrian pine||25 x 7||Low||Upright selection of Austrian pine; dark green needles; prone to snow damage|
|Pyrus||calleryana||‘Cleveland Select’ or ‘Glen’s Form’||Chanticleer pear||35 x 15||Med||Glossy green leaves in summer; red-purple fall color; white flowers in spring; few fruits|
|Pyrus||ussuriensis||‘Bailfrost’||Mountain Frost® pear||25 x 15||Med||Glossy green leaves in summer; red-purple fall color; white flowers; few fruits|
|Pyrus||x||‘NCPX1’ PP 26159||Javelin pear||25 x 15||Med||Leaves emerge purple and turn to bronze-green; tightly columnar|
|Quercus||robur||‘Fastigiata’||Upright English oak||40 x 12||Med||Upright form of English oak; prone to snow damage|
|Quercus||robur||‘Skyrocket’||Skyrocket English oak||35 x 10||Med||More columnar form of Fastigiate English oak|
|Quercus||robur x alba||‘Crimschmidt’||Crimson Spire™ oak||40 x 15||Low-Med||Dark green foliage in summer; rusty red fall color; not susceptible to iron chlorosis; holds leaves into winter|
|Quercus||robur x alba||‘JFS-KW1QX’||Street Spire oak||45 x 15||Med||Green leaves that turn red in the fall; leaves drop in the fall and are not persistent|
|Quercus||robur x bicolor (x warei)||‘Long’||Regal Prince® oak||45 x 15||Low-Med||Dark green foliage in summer; brownish-yellow fall color; holds leaves into winter|
*E. Hammond, horticulture agent, Colorado State University Extension; J. Klett, Extension Specialist, Colorado State University; and A.S. O’Connor,
horticulture agent, Colorado State University Extension.