North Dakota Tree Handbook
Quick Reference Legend
The Quick Reference to Tree and Shrub Characteristics (Table 2-1) gives, at a glance,
the plant's ability to meet the needs of the user with respect to 26 different plant and
adaptation characteristics. Spend a few minutes reviewing the following definitions to
better utilize the data contained.
Determination of adaptability or representation of characteristics is based on the best
literature, experience and observation available. Trees and shrubs have the ability to do
the unexpected. They may die when planted in ideal situations and they can do well when
planted on very challenging sites. Recommendations are based on average situations likely
to be found throughout North Dakota. Individual experiences may vary.
Y = Yes, best, well adapted, or representative of the characteristic. Generally
recommended for a particular application. Presents the greatest number of desirable
characteristics with the fewest number of drawbacks for each listed characteristic.
M = Moderately well adapted, or representative of the characteristic. May work for a
particular application or have potential but will require greater inputs to be successful.
Still provides predominantly desirable benefits, but exhibits a few more negative
attributes for some of the listed characteristics.
N = No, not well adapted or representative of the characteristic, or generally not
recommended. Perceived or actual negative attributes outweigh any potential positive
benefits for the listed characteristic.
Plant and Adaptation Characteristics
The numbers listed before each plant and adaptation characteristic below correspond to
the numbers in parenthesis under the column headings in Table 2-1, "Quick Reference
Guide to Tree and Shrub Characteristics."
- Twenty Year Height, Mature Height and Crown Spread - Assumes healthy stock
planted on the most appropriate sites with good to excellent weed control. Less than ideal
conditions or maintenance will result in greater mortality and stunted growth. Generally,
tree heights and crown spread will decrease from east to west across North Dakota.
- Growth Rate - Assumes optimum growing conditions. Different species exhibit
growth spurts at different stages of development. Some grow fast immediately after
planting. Some do not grow fast until several years old. Growth rates compared to 20 year
heights, may not seem appropriate but in fact reflect the different growth characteristic
of each plant.
Slow = < 1 foot per year.
Med = 1-2 feet per year.
Fast = > 2 feet per year.
- Landscape - Appropriate for planting in urban settings such as yards, boulevards,
parks, etc. Note: Certain varieties released in the nursery trade have been selected to
eliminate objectionable characteristics; e.g., (thornless honeylocust vs. common
Y = Has few if any objectionable characteristics that would
require extra maintenance efforts.
M = Has a few characteristics that are not appropriate for
a landscape setting, that with advance planning, can be
N = Actual or perceived drawbacks of this plant make it
unacceptable in a landscape planting.
Y = Obvious color, shape or structure when viewed from
M = Unique color, shape or structure when viewed up close.
N = Inconspicuous color, shape or structure when viewed
- Usable Fruit - Fruit is consumable by humans.
Y = Commonly used as a food.
M = Infrequently used, varying with individuals or cultural
N = Rarely or not used as a food.
- Fall Leaf Color - Indicates the normal fall color of leaves, however, numerous
environmental and soil conditions may affect ultimate coloration.
RED = red
YEL. = yellow
ORG. = orange
BRN. = brown
PUR. = purple or reddish purple
NONE = do not turn color in the fall.
- Wildlife Cover - Viable wildlife populations are dependent upon the presence of
four habitat cover types. The listed tree or shrub provides one or more of the following
cover types: nesting, loafing, escape, winter cover.
Y = Provides three or more of the cover types.
M = Provides two cover types.
N = Provides only one of the cover types.
- Wildlife Food - Provides food for wildlife. Of particular concern is the plant's
ability to provide needed food for resident wildlife throughout the winter.
Y = Excellent source of winter food.
M = Provides food prior to winter. Most food is utilized
during the growing season.
N = No food supplies carried into winter and little food
available or utilized during the growing season.
- Windbreaks - Particular plant's ability to withstand the exposed conditions,
moisture stress, and limited maintenance commonly associated with conservation and
Y = Ability to withstand exposed field conditions and
eventual vegetative competition.
M = Ability to withstand exposed field conditions but
survival and growth rates are significantly reduced.
N = Inability to withstand exposed conditions and
- Forest Products - Particular plant's value as a forest product such as Christmas
trees, poles, pulp, lumber, chemicals, pharmaceuticals, food processing (e.g. smoking
meats), etc. Only the ability to produce the material is considered. Availability of
markets is not addressed.
Y = Currently utilized in North Dakota.
M = Currently utilized in other places but not North Dakota.
N = Currently not utilized for forest products.
- Suckers - Plant's ability to produce root suckers or basal trunk sprouts. Does
not include basal sprouts arising from the stump when a tree is cut.
Y = Commonly develops root suckers.
M = Rarely develops root suckers unless roots are damaged
but may produce basal trunk sprouts or spread by
N = Does not develop root suckers or basal trunk sprouts.
- Powerlines - Applicability to planting under powerlines.
Y = Tree and shrub species that are appropriate for planting
under or near powerlines. Mature trees under most
North Dakota conditions grow 25 feet or less. These
trees do not require significant pruning to eliminate
problems for public safety or reliable service.
M = Tree and shrub species that may reach an ultimate height
where they are not compatible with power lines. These
species may not reach their full height on a poor soil
condition whereas on a fertile, well watered site the
tree may achieve a taller mature height.
N = Trees that should not be planted under or near powerlines
due to excessive height.
Certain trees rated M or N, particularly those with narrow growth habit, can be
compatible if offset at planting to minimize contact with powerlines. For further
information, contact your city forester, nurseryman or electric utility before planting
trees under or near powerlines.
- USDA Hardiness Zones - The northern limit of the upper
Great Plains in which a particular plant may be expected to do well within the range of
temperatures given. (See map on page II-28.)
North Dakota Hardiness/Adaptation Zones - Assists in the selection of species suitable
to various parts of the state. Tree and shrub species are designated to various zones by
their interaction to overall climatic factors: moisture, temperature and general soil
conditions. Zone A is considered the most favorable for woody plant survival and
adaptation, while Zones B and C are progressively less favorable. More favorable sheltered
sites, e.g. snow cover, wind protection, supplemental irrigation, etc., will allow
particular woody plants to be grown in zones beyond those recommended.
Woody plants designated with an asterisk (*) are particularly difficult to categorize by
zone due to native habitat, variability in seed source, cultivar hardiness or other
factors. Mature representatives of these species are in trial plantings in one or more
North Dakota zones and have shown success in survival and establishment. These plants may
be from particular winter hardy seed sources. Nursery stock propagated from these sources
or other mature specimens currently growing in the northern plains may be better adapted
for the North Dakota environment. There are numerous cultivars of apples and ornamental
crabapples which are not adaptable to northern plains conditions. Check with knowledgeable
authorities for specific woody plant cultivars adaptable to your area. (See map on page
- Soil Adaptation - Modification of limiting soil characteristics may allow species
to be planted on soils not otherwise suitable. Species listed in this handbook are assumed
to be suitable for planting on all other types of soil not described below, as long as
climatic, geographic and topographic characteristics are appropriate.
Dry Soils - These soils are well drained to very droughty. Tree species are limited.
Sand blasting and water stress are the principle concerns. No additional water reaches the
plants from off site during the growing season. Bedrock may limit rooting depth.
Dry soil conditions can be corrected with irrigation. However, if the species is not
adapted to a dry site, the irrigation must continue for the life of the plant. For some
situations this irrigation need could approach 100 gallons per day during the summer for a
large deciduous tree.
Y = Ability of established plants to survive and grow
satisfactorily on excessively drained or shallow,
M = Same capability as plants designated in Y, but may not
survive extended drought.
N = Established plants will require supplemental water (e.g.
snow collection, high water table, irrigation, etc.).
Wet Soils - An established plant's ability to withstand saturation or surface
pond-ing. NOTE: Most plants will withstand extended periods of flooding when dormant.
Excess wetness may be corrected with subsurface tiling or surface drainage, but may
require cooperation from neighbors and will require periodic maintenance for the life of
Drained soils may periodically become too wet to support nonadapted species during times
of flood or excessive precipitation.
Y = Ability to withstand flooding or soil saturation for
more than three weeks during the growing season.
M = Ability to withstand flooding or soil saturation for
one to three weeks during the growing season.
N = Inability to withstand flooding or soil saturation for
one to seven days during the growing season.
Sodic/Saline Soils - Excess soluble salts or sodium in the soil limit the
ability of trees to survive. Soluble salts restrict the availability of water to the
Y = Established plants able to withstand moderate salinity
from 8 to 16 deciSiemens per meter (millimhos per
M = Established plants able to withstand slight salinity from
4 to 8 deciSiemens per meter (millimhos per centimeter).
N = Established plants not able to with stand saline
conditions exceeding 4 deciSiemens per meter (millimhos
Certain plants will do well on soils that are moderately saline. Deterioration of a
soil's physical properties, including the development of a dense soil layer associated
with sodium salts, limits rooting depth. Many of these soils are droughty and the ability
of woody plants to withstand extended periods of drought is limited. Even adapted species
will not grow to their maximum potential and chances of mortality increase on sodic and
saline soils. The problem of excessive salt in the soil is nearly impossible to correct.
Any methods that might work are prohibitively expensive. (See glossary for additional
information under Saline Soil.)
Alkaline Soils - This chemical property of soils affects tree survival. Tree and
shrub survival decreases as pH (alkalinity) increases. Few plants will do well on soils
that have a pH in excess of 8. In certain situations soil pH can be lowered with the
addition of soil amendments such as sulfur. If successful, this practice will likely need
to be repeated throughout the life of the tree.
Y = Ability to survive and perform satisfactorily on soils
with a pH greater than 8.0.
M = Ability to survive and perform well on soils with a pH
of 7.5 to 8.0.
N = Ability to survive and perform well on soils with a pH
lower than 7.5.
- Temperature Adaptation
Cold/Wind - The ability of established plants to withstand intense cold and
desiccating wind. This is of particular importance to those plants that are outside, or on
the edge, of their hardiness zone. Site specific microclimates may allow plants to survive
outside their native range. (Use same legend as under Hot/Wind below.)
Hot/Wind - The ability of established plants to withstand hot temperatures and
dry summer winds that exert a strong transpiration demand, especially on young plants.
Survival can be increased by providing irrigation and mulch. (See legend below.)
Y = Established plant is able to withstand North Dakota
temperature/wind extremes without supplemental care
beyond initial weed control.
M = Established plant will survive if protected from
temperature/wind extremes in a favorable microclimate
(e.g. in developed urban settings or protected by
established windbreaks, native timber stands or in
N = Established plants of certain seed sources will often
not survive North Dakota temperature/wind extremes even
when located in a favorable microclimate. Select a
better adapted seed source or species.
- Shade - Plant's ability to do well when shaded from direct sunlight for
most of each day during the growing season.
Y = Tolerant
M = Moderately tolerant
N = Intolerant
- Establishment - Plant's ability to withstand the shock of planting, moisture
stress and windburn that often threaten newly planted trees. (Based upon survival within
the first three years after planting.)
Y = Plant survives planting well, with little extra care
beyond occasional weed control.
M = Plant will do well but will need good weed control and
supplemental water on occasion for the first few years.
N = Plant will do well but only if pro vided excellent weed
control, extra water and protection from sand blasting
and desiccating winds.
Wind protection could include wood shingles, grass or crop rows, other tree/shrub rows,
snow fence, etc. In addition, snow trapped by these barriers protects new seedlings from
winter desiccation and provides needed water during the growing season.
- Snow/Ice - Plant's ability to withstand normal snow drifts and ice loading,
without severe deformity or breakage, such as commonly found on the windward edges of
multiple row plantings.
Y = Withstands heavy snow/ice loading with minimal damage.
M = Heavy snow/ice loads cause damage to small limbs and
branches, but basic plant form and function is maintained.
N = Heavy snow/ice loads cause severe deformity and destruction
to plant form and function, respectively.
Note: Throughout this quick reference, shrubs are generally listed as moderate (M) even
though they are often broken or deformed from snow and ice loading. Most shrubs, however,
have the ability to regrow vigorously and usually provide continuous habitat and wind
protection. Most deciduous trees handle snow well once the canopies grow above the snow
- Unique Features - Particular plant features that are unique, interesting or of
particular importance to the successful utilization of the plant listed.
Table 2-1. Quick reference guide to tree and shrub characteristics (table 2-1 is a PDF file)