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Cass County Extension |
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Evergreen Trees |
Colorado Spruce
- Dense, symmetrical, pyramidal form; varies from green through blue-green, bluish to
silver-blue. 1" needles are very stiff and spiny. Shorter lived in heavy soil. Need
good drainage. Canker and Needlecast diseases are a serious problem; worse under stress
conditions. Excellent steel blue cultivars available; `Hoopsii' is one of the best. `Fat
Albert' and `Foxtail' have a dense, upright pyramidal form; good blue color. Compact dwarf
cultivars (Baker Blue, Montgomery Blue and Globe
Blue) are steel blue in color and very slow growing but excellent for home
landscaping.
Black Hills Spruce
- Not as attractive as the Colorado spruce; less dense. 1/2" needles are green to
slightly blue-green in color. Faster growing when young than the Colorado spruce; more
drought tolerant but more susceptible to mites. Less disease problems; needs good
drainage. Dwarf Alberta Spruce is very slow
growing with an extremely compact conical growth habit. Its fine needles suffer from
winter drying; burns badly. May be short lived. Very susceptible to spider mites.
Norway Spruce - Loosely branched tree with pendant secondary branches. Less drought tolerant and dense than above species; greener needles with a glossy sheen. 4-8" long, woody cones. Loses its form with age. Declines in dry years. Compact dwarf cultivars include: Birds Nest Spruce is very slow growing, spreading and flat topped; a bit borderline in hardiness. Dwarf Norway Spruce (broad globe shape; hardy).
Serbian Spruce - Narrow pyramidal tree with dark green needles above contrasted by silvery-white beneath. Plant in a protected spot; may winterburn. Questionable hardiness. Dwarf Serbian Spruce is a dense dwarf form usually broader than tall. Black Spruce has a conical shape with dull blue green needles; does well in high moisture sites of eastern Minnesota. Blue Nest Spruce is a dense mound shaped form; blue green needles.
Scotch Pine -
Pyramidal when young but becomes rounded and open with age; self elevating. Upper trunk
and branches coppery orange in color; needles
2-4" long and somewhat twisted. Irregular shaped tree; faster growing than Ponderosa.
Too large for small lots. 'Watereri' is steel-blue in color, slower growing and densely
pyramidal to flat topped. Dwarf Scotch Pine and Sentinel Pine (columnar
shape) merit trial.
Ponderosa Pine -
Pyramidal in shape; become more open with age. 4-6" needles; darker green than
Scotch. Good drainage required; drought tolerant. Self elevating. Best pine for general
use; too large for small lots.
Austrian Pine -
Stiff thick 4-7" dark green needles; Silver-white colored sticky buds. Pyramidal when
young but becomes flat topped with age. Winter burn can be a serious problem; borderline
in hardiness.
Swiss Stone Pine - Narrow pyramidal growth habit; slow growing. Five needles per bundle. Very attractive; drought tolerant. Denser, narrower and much better adapted than White Pine. Siberian Stone Pine is taller than species with shorter needles; both are very winter hardy.
Balsam Fir - Soft flat green needles in two rows; thicker and denser than Douglas Fir. Becomes sparser with age. Slow growing. Prefers acidic soil and adequate moisture. Hardy but spruce are better adapted. Fraser Fir is similar but more compact. Very slow growing; questionable adaptation.
Siberian Larch -
Delicate, feathery bright green needles; drop in the
fall. Has good yellow fall color. Rapid growing with good moisture but must transplant in
the fall; very early spring growth. American Larch is a boggier tree; not as
satisfactory here. European Larch also performs satisfactory in Northern Plains.
(Actually a deciduous tree).
Pyramidal Juniper
- Slender pyramidal to columnar in growth habit; varying in color from green to silvery
blue-green. Capable of maturing at 10-20'; annual pruning needed to keep in bounds once
desired height has been reached. Mites can be a problem. Recommended selections of the Rocky
Mountain Juniper include: 'Grizzly Bear' (bluish
gray color and broader than 'Medora'), 'Medora', 'Welchii' (blue-green color; 15-20'), and 'Wichita Blue'
(bluish green color; pyramidal form). Eastern Red-cedar is faster growing but due
to its purple-brown winter color, lack of branch density and questionable hardiness of
cultivars, it is not generally recommended except for shelter plantings. `Taylor'
(columnar; dark green color).
American Arborvitae - Loose pyramidal growth habit; tends to develop
multiple trunks. Dark green in color. Gets too large for single story homes; annual
pruning is needed once desired size is reached. Occasional winter desiccation may occur. Pyramidal Arborvitae (good columnar form;
occasional winter burn. 25'+), 'Brandon' (columnar and dark green color; occasional winter
burn), `Emerald' (severe winter burn), 'Holmstrup' (dense narrow conical shape; bright
green color; layered look; slow growing; occasional winter burn). Techny Arborvitae (dense pyramidal form; commonly
sheared into a globe shape). Siberian Arborvitae
(broad pyramidal form. Coarser foliage, more dense, very hardy and lower growing than the
species. Resistant to winter burn). Compact golden or yellow-leafed cultivars are more
subject to winter burn.
This page was last updated March 2003
| Todd Weinmann, Extension Horticulturist & Master Gardener Coordinator |
| Phone: (701) 241-5707 |
| E-mail: tweinman@ndsuext.nodak.edu |