Alberta Range Plants and Their Classification

Alberta rangelands consist of native and introduced plant species that exist in plant communities. These lands are made up of grasses, sedges, forbs, shrubs and even trees. Rangelands provide an important source of forages for domestic and native animals as well as protection to the soil and watersheds.

Specific to the plant species found in a particular area at any point in time, plant communities group various population sizes of plants occurring together on the landscape. These communities are managed in pastures, grazing reserves and ranches as range ecosystems, which are complex collections of living and non-living (biotic and abiotic) parts that interconnect with each other within the rangeland environment.

This complex network of individual biotic and abiotic entities works together cohesively as a single unit. This unit functions as a continuum of cause-and-effect relationships that is never ending as long as the ecosystem can support life in any form. If one part of this unit is affected, the whole network and every individual part within it is affected as well.

Rangeland environments and range ecosystems are inherently complex. However, they are largely based on individual plants that are important as forage for livestock and herbivorous wildlife. To maintain the site stability, stand longevity and structural integrity of their communities, range managers must know these plants and their various structural and habitual characteristics.

Using this factsheet

In this factsheet, each range plant species is shown under two names: a common (English) name and a scientific (Latin or Greek) name. This presentation is so that the plants can be sorted into the various taxonomic genera, families and classes based on that species’ unique physical characteristic[s] and to help managers find more information on that particular plant. See the tables later in this factsheet.

Because a plant can have several different common names in different parts of the province or country, the scientific name helps pinpoint the identity of that plant more accurately, especially if it is discussed among range managers all over the globe.

Range plants can also be grouped based on various characteristics like plant type, lifespan, origin, response to grazing (or other disturbances like fire and drought) and forage value. In the “Definitions” section below, Plant type groups various species with similar physical characteristics to define them as grasses, grass-like plants, forbs, shrubs or trees.

Also in the section below, a plant’s life span, noted as an annual, biennial or a perennial, determines the longevity of a plant. Origin refers to plants indigenous to North America or that have been introduced recently from other continents. Plants with varying responses to grazing are grouped as decreasers, increasers or invaders.

Finally, forage value, grouped as good, fair, poor and/or poisonous, is determined by palatability (acceptance by grazing animals based on taste), nutritional value and abundance for grazing. Poisonous plants are deemed as such if they contain toxins harmful to grazing animals.

Range plants can also be classified according to what part of the growing season they tend to grow best in. Most of the plants listed in this publication show a “cool season” response where the major portion of their growth occurs during spring and early summer when temperatures range from 18°C to 24°C. Some plants, including blue grama (Bouteloua gracilis), little bluestem (Schizachyrium scoparium) and red three-awn (Aristida purpurea var. longiseta), are classed as “warm season” plants because they grow slowly during the early part of the season, but grow best in late spring and summer when temperatures range from 32°C to 35°C.

Definition of plant characteristics

Plant type

Grasses - herbaceous plants with narrow, long, parallel-veined leaves and hollow, jointed stems. Spikes of small seeds borne between two scales are found at the top portion of these stems.

Grass-like plants – look very similar to grasses but have solid stems (not hollow) that are often three-sided and not jointed. Leaves are no different from grasses. These are made up of sedges and rushes.

Forbs – herbaceous, broad-leaved plants with annual tops and leaves with net-like veins (range weeds and flowers).

Shrubs – woody, often deciduous perennials with stems that live over the winter and branch out from near the base or at ground level.

Trees – woody, single-stemmed perennial plants that reach a mature height of at least 3 metres.

Life span

Annual plants – live only for one growing season. They do not come up a second year from roots or a crown but rather from seeds deposited by a parent plant.

Biennial plants – require two years to complete life cycle. Vegetative growth is focused during the first year, then in the second year, flowering, fruit production and death.

Perennial plants – live and reproduce year after year, producing leaves, stems and flowers for more than two years from the same root system.

Origin

Native plants – those plants that are indigenous to North America.

Introduced plants – plants that have been brought in from outside North America in the last few centuries and are not usually present in the original plant community.

Response to grazing

Grazing response - the reaction a species has to continuous defoliation, usually by grazing and hoof damage. Soil type, moisture levels and climate ultimately affect the response to defoliation for any one species. Where a species is a primary decreaser in one environmental condition, it may become an increaser in a different environmental situation. (Note that the response of plants to defoliation is not limited to grazing animals. The response is also related to the effects of fire, insect damage and drought.) Types of range plants responses are grouped as follows:

• Decreasers – plant species of an original or climax plant community that decrease in relative amount with continued disturbances, such as heavy grazing. These plants may be either highly palatable, being continually sought out by grazing animals and often the first ones to be defoliated throughout the growing season, or they may lack certain physical characteristics that would otherwise help them in their recovery.
• lncreasers – plant species of an original plant community that will increase in relative amount for period of time under continued disturbances such as heavy grazing. Increasers will generally take over the community. Increaser plants are typically those adapted to heavy defoliation because they grow close to the ground and possess physiological attributes that allow them to recover quickly from grazing and hoof damage. They may also be less palatable and therefore less desirable to grazing animals. Such plants need to be monitored since they are a sign of heavy grazing (such as high intensity, high frequency grazing) and can increase in abundance beyond what is acceptable. Overuse, however, can cause even these plant types to decrease in the community.
• Invaders – commonly are weedy plants that have established themselves in a plant community because the more desirable species have died out from heavy grazing and trampling. A high proportion of invader species is generally a sign of excessive grazing pressure; however, some noxious range weeds such as leafy spurge (Euphorbia esula), spotted knapweed (Centaurea maculosa) and even aspen poplar (Populus tremuloides) are capable of invading healthy range ecosystems.

• Good – plants are nutritious, highly palatable and tend to produce abundant forage in their original community.
• Fair – plants are very likely to produce adequate nutrients when consumed; however, they may not have substantial palatability or do not produce an abundance of forage in their original community.
• Poor – plants that lack adequate nutrients for the grazing animal. Also, most plants that contain anti-nutritional factors that cause reduced intake or possible illness are also classed as having “poor” forage value.
• Poisonous – plants classed as “poor” quality forage due to compounds or toxins that cause illness or death of grazing animals.

Common name	Scientific name	Life span	Origin	Grazing response	Forage value
Absinthe	Artemesia absinthium	Perennial	Introduced	Invader	Poor
Alfalfa	Medicago sativa	Perennial	Introduced	Invader	Good
Alpine milk vetch	Astragalus alpinus	Perennial	Native	Increaser	Fair
Alumroot	Heuchera richardsonii	Perennial	Native	lncreaser	Poor
American milk vetch	Astragalus americanus	Perennial	Native	Decreaser	Good
American vetch	Vicia americana	Perennial	Native	Decreaser	Good
Ascending purple milk vetch	Astragalus striatus	Perennial	Native	Increaser	Fair
Arnicas	Arnica spp.	Perennial	Native	lncreaser	Poor
Aster	Aster spp.	Perennial	Native	lncreaser	Fair
Baby’s-breath	Gypsophila paniculata	Perennial	Introduced	Invader	Poor
Ball-head sandwort	Arenaria congesta	Perennial	Native	lnvader	Poor
Balsam-root	Balsamorhiza sagittata	Perennial	Native	lncreaser	Fair
Baneberry	Actaea rubra	Perennial	Native	Increaser	Poor and poisonous
Bastard toad-flax	Comandra umbellata	Perennial	Native	Increaser	Poor
Beard-tongue	Penstemon spp.	Perennial	Native	Increaser	Fair
Bird’s-foot trefoil	Lotus corniculatus	Perennial	Introduced	Invader	Good
Black medick	Medicago lupulina	Perennial	Introduced	Invader	Good
Blazing star	Liatris spp.	Perennial	Native	Increaser	Poor
Bluebell	Campanula rotundifolia	Perennial	Native	lncreaser	Poor
Blue-eyed grass	Sisyrinchium montanum	Perennial	Native	Increaser	Poor
Broomweed	Gutierrezia sarothrae	Perennial	Native	Increaser	Poor and poisonous
Buffalo bean/golden bean	Thermopsis rhombifolia	Perennial	Native	Increaser	Poor
Buttercup/crowfoot	Ranunculus spp.	Perennial	Native	lncreaser	Poor
Canada anemone	Anemone canadensis	Perennial	Native	Increaser	Poor
Canada milk vetch	Astragalus canadensis	Perennial	Native	Decreaser	Good
Canada thistle	Cirsium arvense	Perennial	Introduced	Invader	Good
Cicer milk vetch	Astragalus cicer	Perennial	Introduced	Increaser	Good
Cinquefoil	Potentilla spp.	Perennial	Native	lncreaser	Poor
Clover	Trifolium spp.	Perennial	Introduced	lncreaser	Good
Common horsetail	Equisetum arvense	Perennial	Native	Increaser	Poor
Common nettle	Urtica dioica	Perennial	Native	Increaser	Poor
Common peppergrass	Lepidium densiflorum	Annual	Native	Invader	Poor
Common scouring rush	Equisetum hyemale	Perennial	Native	Increaser	Poor
Common tansy	Tanacetum vulgare	Perennial	Introduced	Invader	Poor
Common yarrow	Achillea millefolium	Perennial	Native	lncreaser	Poor
Corydalis/touch-me-not	Corydalis & Impatiens spp.	Perennial	Native	Increaser	Poor
Cow parsnip	Heracleum lanatum	Perennial	Native	Decreaser	Good
Cream-coloured pea vine	Lathyrus ochroleucus	Perennial	Native	Decreaser	Good
Cut-leaved anemone	Anemone multifida	Perennial	Native	lncreaser	Poor
Dandelion	Taraxacum officinale	Perennial	Introduced	lnvader	Fair
Death camas	Zigadenus venenosus	Perennial	Native	lncreaser	Poor and poisonous
Dock/sorrel/wild begonia	Rumex spp.	Perennial	Native	Invader/Increaser	Poor
Dotted blazing star	Liatris punctata	Perennial	Native	Decreaser	Good
Drummond milk vetch	Astragalus drummondii	Perennial	Native	Decreaser	Good
Early blue violet	Viola adunca	Perennial	Native	Increaser	Poor
False dandelion	Agoseris glauca	Perennial	Native	lncreaser	Fair
False hellebore	Veratrum eschscholtzii	Perennial	Native	Increaser	Poor and poisonous
Field chickweed	Cerastium arvense	Perennial	Native	Increaser	Fair
Fireweed/willow-herb	Epilobium spp.	Perennial	Native	Increaser	Fair
Fleabane	Erigeron spp.	Perennial	Native	lncreaser	Poor
Gaillardia	Gaillardia aristata	Perennial	Native	lncreaser	Poor
Geranium	Geranium spp.	Perennial	Native	Decreaser	Good
Goat’s-beard	Tragopogon dubius	Biennial	Introduced	lnvader	Poor
Goldenrod	Solidago spp.	Perennial	Native	lnvader	Poor
Ground plum	Astragalus crassicarpus	Perennial	Native	Decreaser	Good
Gumweed	Grindelia squarrosa	Biennial	Native	lncreaser	Poor
Hairy golden aster	Heterotheca villosa	Perennial	Native	lncreaser	Fair
Hawksbeard	Crepis spp.	Perennial	Native	Decreaser	Fair
Hawkweed	Hieracium spp.	Perennial	Native	Decreaser	Good
Hedysarum	Hedysarum spp.	Perennial	Native	lncreaser	Fair
Indian milk vetch	Astragalus aboriginum	Perennial	Native	Increaser	Good
Knapweed	Centaurea spp.	Biennial	Introduced	lnvader	Poor
Lamb’s-quarters	Chenopodium album	Introduced	Annual	lnvader	Poor
Larkspurs	Delphinium spp.	Perennial	Native	Increaser	Poor and poisonous
Leafy spurge	Euphorbia esula	Perennial	Introduced	lnvader	Poor and poisonous
Little clubmoss	Selaginella densa	Perennial	Native	Increaser	Poor
Locoweed	Oxytropis spp.	Perennial	Native	lncreaser	Poor and poisonous
Long-leaved chickweed	Stellaria longifolia	Perennial	Native	Increaser	Fair
Lupine	Lupinus spp.	Perennial	Native	lncreaser	Poor and poisonous
Meadow rue	Thalictrum spp.	Perennial	Native	lncreaser	Poor
Missouri milk vetch	Astragalus missouriensis	Perennial	Native	Increaer	Fair
Moss phlox	Phlox hoodii	Perennial	Native	lncreaser	Poor
Narrow-leaved milk vetch	Astragalus pectinatus	Perennial	Native	lncreaser	Poor and poisonous
Narrow-leaved wormwood	Artemisia dracunculus	Perennial	Native	lncreaser	Poor
Northern bedstraw	Galium boreale	Perennial	Native	Increaser	Poor
Northern gentian	Gentianella amarella	Annual / Biennial	Native	Increaser	Poor
Ox-eye daisy	Chrysanthemum leucanthemum	Perennial	Introduced	Invader	Poor
Paint-brush	Castilleja spp.	Perennial	Native	Increaser	Poor
Pasture sage	Artemesia frigida	Perennial	Native	Increaser	Poor
Plantain	Plantago spp.	Annual	Native	Increaser	Poor
Prairie clovers	Petalestemon spp.	Perennial	Native	Increaser	Fair
Prairie cone-flower	Ratibida columnifera	Perennial	Native	Increaser	Poor
Prairie crocus	Anemone patens	Perennial	Native	lncreaser	Poor
Prairie onion	Allium textile	Perennial	Native	lncreaser	Fair
Prairie sage	Artemisia ludoviciana	Perennial	Native	lncreaser	Poor
Purple milk vetch	Astragalus dasyglottis	Perennial	Native	Increaser	Fair
Purple pea vine	Lathyrus venosus	Perennial	Native	Decreaser	Good
Pussy-toes/everlasting	Antennaria spp.	Perennial	Native	Increaser	Poor
Prostrate pigweed	Amaranthus graecizans	Annual	Native	lnvader	Poor
Rock cress	Arabis spp.	Biennial	Native	Increasers	Poor
Russian thistle	Salsola kali	Annual	Introduced	lnvader	Poor
Sainfoin	Onybrychis viciifolia	Perennial	Introduced	Invader	Good
Scarlet mallow	Sphaeralcea coccinea	Perennial	Native	lncreaser	Poor
Scentless chamomile	Matricaria perforata	Perennial	Introduced	Inavder	Poor
Seaside arrow-grass	Triglochin maritima	Perennial	Native	lncreaser	Poor and poisonous
Showy milkweed	Asclepias speciosa	Perennial	Native	Increaser	Poor and poisonous
Silver saltbush	Atriplex argentea	Annual	Native	Increaser	Fair
Slender milk vetch	Astragalus flexuosus	Perennial	Native	Increaser	Fair
Sow thistle	Sonchus spp.	Perennial	Introduced	Invader	Fair
Spiny ironplant	Haplopappus spinulosus	Perennial	Native	Increaser	Poor
Star-flowered solomon’s seal	Smilacina stellata	Perennial	Native	Increaser	Fair
Sticky geranium	Geranium viscosissimum	Perennial	Native	Decreaser	Good
Strawberry blite	Chenopodium capitatum	Annual	Introduced	Invader	Poor
Sweet clover	Melilotus spp.	Biennial	Introduced	lnvader	Good; mature plants become poor
		Three-flowered avens
(old man’s whiskers)	Geum triflorum	Perennial	Native	lncreaser	Poor
Timber milk vetch	Astragalus miser	Perennial	Native	Increaser	Poor and poisonous
Tumbleweed	Amaranthus albus	Annual	Native	Invader	Poor
Water hemlock	Cicuta maculata	Perennial	Native	Increaser	Poor and poisonous
Water parsnip	Sium suave	Perennial	Native	Increaser	Poor
Water smartweed	Polygonum amphibium	Perennial	Native	Increaser	Poor
Wavy-leaved thistle	Cirsium undulatum	Perennial	Native	Increaser	Fair
Western Canada violet	Viola canadensis	Perennial	Native	Increaser	Fair
Western wood lily	Lilium philadelphicum	Perennial	Native	Decreaser	Fair
White camas	Zigadenus elegans	Perennial	Native	Increaser	Poor and poisonous
Wild blue flax	Linum lewisii	Perennial	Native	Increaser	Poor
Wild licorice	Glycyrrhiza lepidota	Perennial	Native	Increaser	Poor
Wild strawberry	Fragaria virginiata	Perennial	Native	Increaser	Poor
Yellow umbrella plant	Eriogonum flavum	Perennial	Native	lncreaser	Poor