A mature plant that tillers at the base is very attractive when it is in full bloom. Also, the foliage is somewhat ornamental and remains attractive throughout the growing season. This plant is not easily confused with any other species, perhaps the most similar being Dalea candida (White Prairie Clover), which has white flowers and foliage that is lighter-colored and somewhat longer. In the past, the scientific name for this plant was Petalostemum purpureum. Return

This native perennial plant is unbranched and ¾–3' tall. Older plants may tiller at the base and send up multiple stems, creating a bushy effect. The central stem is slightly ridged and hairless. The odd-pinnate compound leaves alternate as they ascend the stem. They consist of 3-7 leaflets and tend to be quite short, approximately 2-5' long. Each leaflet is dark green, linear in shape, and about 1' long and 1/8' across. There are scattered translucent dots across the surface. At the top of the plant is a dense cylindrical spike of flowers about 1-2' long and about half as much or less across. Each purple flower is about 1/3' across, with 5 small petals and 5 golden anthers that protrude outward. These flowers bloom together as a flowery wreath at the bottom of the spike, which gradually moves upward at the season progresses. There is no noticeable floral scent. The blooming period occurs from early to mid-summer, and lasts about 1-1½ months. The root system consists of a stout taproot that runs deep into the ground. The seeds travel only a short distance from the mother plant when the cylindrical spikes are shaken by the wind. Cultivation

General: The Legume family (Fabaceae). Purple prairie clover is a native, warm season, herbaceous, perennial, leguminous forb. The plant has an erect type growth habit that typically grows to a height of

30 to 90 cm. It can be identified by its alternate, pinnately compound leaves and multiple stems which arise annually from a woody caudex. The inflorescence is a terminal spike (2-4 cm), numerous, many-flowered and cylindrical in shape. The flower petals which are rose-purple with projecting gold-orange anthers are small and simple compared to many pea shaped flowers of typical legumes. The calyx is densely villous. Flower petals are 6 mm long, 4 of the petals and the five stamens are joined near the calyx tip and the banner petal is separate. The first flowers to bloom are located at the bottom of the spike and the circle of flowers moves upward along the spike as new buds open and old flowers fade. Pollination is accomplished by a host of native insects ranging from bumblebees to beetles (Art, 1991). The fruit is a one seeded legume pod enclosed by the persistent calyx which is 2-2.5 mm long. The legume seed is yellowish-green to brown and is 1.5-2.0 mm long and punctuate. Purple prairie clover flowers the last of May to September in the central Great Plains. It flowers some what later (July-August) in the northern Great Plains. This plant is deep rooted with a 2.0 meter tap root. It also has three to seven lateral roots within the upper 30 cm of tap root which extend horizontally up to 45 cm before turning downward (Weaver, 1954).

Distribution: For current distribution, please consult the Plant Profile page for this species on the PLANTS Web site. Purple prairie clover ranges from Indiana to Saskatchewan and Montana, south to Tennessee, Arkansas, Texas and New Mexico. It is also found in Alabama and has been introduced east into New York State.

Habitat: Purple prairie clover occurs in prairies, rocky open glades, along railroad tracks, and rocky or open woods.

violet prairie clover, red tassel flower, thimbleweed, and wanahcha (Lakota)

Purple Prairie Clover occurs occasionally in central and northern Illinois, but is rare or absent in southern Illinois (see Distribution Map). It is not common in areas that have been disturbed by modern development. Habitats include mesic to dry black soil prairies, gravel prairies, sand prairies, hill prairies, typical savannas and sandy savannas, limestone glades, and sandy hills or dunes near Lake Michigan. Recovery from occasional wildfires is good. Faunal Associations

(key to state/province abbreviations)
UNITED STATES

AL	AZ	AR	CO	IL	IN
IA	KS	KY	LA	MI	MN
MS	MO	MT	NE	NM	NY
ND	OH	OK	SD	TN	TX
WI	WY

CANADA

AB

BC

MB

ON

SK

More info on this topic.

This species can be found in the following regions of the western United States (according to the Bureau of Land Management classification of Physiographic Regions of the western United States):

BLM PHYSIOGRAPHIC REGIONS [11]:

8 Northern Rocky Mountains

9 Middle Rocky Mountains

10 Wyoming Basin

11 Southern Rocky Mountains

13 Rocky Mountain Piedmont

14 Great Plains

15 Black Hills Uplift

16 Upper Missouri Basin and Broken Lands

Purple prairie clover is indigenous through a large portion of North America. It is distributed  from eastern British Columbia eastward through Manitoba and south to western Alabama and west to Arizona. Frequent to infrequent populations exist in its extreme western extent in eastern Colorado, Wyoming, and Montana and in its extreme eastern extent in Ontario southward to New York and Tennessee [48,63,100,112]. There is considerable overlap of distributions between Dalea purpurea var. purpurea and D. p. var. arenicola, although D. p. var. arenicola's distribution is more restricted to the western Great Plains [49]. Plants database provides a distributional map of purple prairie clover.

Psoralea purpurea Sessé & Moc.:
Mexico (Mesoamerica)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Dalea purpurea Vent.:
Canada (North America)
United States (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Petalostemon standleyanus Rydb.:
Mexico (Mesoamerica)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Petalostemon purpureus fo. albiflorus Horr & McGregor:
Canada (North America)
United States (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Petalostemon purpureus (Vent.) Rydb.:
Canada (North America)
United States (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Canada

Origin: Unknown/Undetermined

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

This species grows on prairies, plains, and hills

in soils ranging from clay loams to loamy sands. Found growing more vigorously on well drained sites and moderately alkaline calcareous soils. Thrives in 40 to 50 cm precipitation zones, but found in suitable sites in the 30 to 38 cm rainfall zones. Purple prairie clover is moderately drought tolerant, has fair fire tolerance in its dormant state, and fairly shade tolerant and medium in competitiveness. Local ecotypes are fairly winter hardy and plants have been found up to about 2,200 meters in elevation in the Rocky Mountains. Purple prairie clover is normally found growing in association with native warm-season grasses such as Sorghastrum nutans, Bouteloua curtipendula, Andropogon gerardii, Schizachyrium scoparium, and Panicum virgatum.

More info for the term: forb

The following description provides general characteristics that may be relevant to fire ecology, and is not meant for identification. Keys for identification are available (e.g. [6,43,48,49,100,108,112]).

Purple prairie clover is a perennial forb, 8 to 35 inches (20-90 cm) tall, with a woody stem. The numerous leaves are 0.4-1.6 inches (1-4 cm) long, with 3 to 7 leaflets. The inflorescence is a 0.4- to 2.6-inch (1-7 cm) spike located at the ends of the branches. Branches are numerous, usually 3 per stem, but sometimes as many as 10 to 12. The mature purple prairie clover has a coarse, nonfibrous root system with a strong woody taproot that is 5.5 to 6.5 feet (1.7-2.0 m) deep. The taproot gives rise to several minutely branched lateral roots. The fruit is a 1- to-2-seeded pod enclosed in bracts [6,48,62,100,112].

Perennial, Herbs, Stems woody below, or from woody crown or caudex, Taproot present, Nodules present, Stems erect or ascending, Stems less than 1 m tall, Plants gland-dotted or with gland-tipped hairs, Stems solid, Stems or young twigs sparsely to densely hairy, Leaves alternate, Leaves clustered on spurs or fasicles, Leaves petiolate, Stipules inconspicuous, absent, or caducous, Stipules setiform, subulate or acicular, Stipules deciduous, Stipules free, Leaves compound, Leaves odd pinnate, Leaf or leaflet margins entire, Leaflets opposite, Leaflets 3, Leaflets 5-9, Leaves glandular punctate or gland-dotted, Leaves glabrous or nearly so, Leaves hairy on one or both surfaces, Inflorescences spikes or spike-like, Inflorescence terminal, Bracts conspicuously present, Calyx 5-lobed, Calyx hairy, Petals separate, Petals clawed, Petals blue, lavander to purple, or violet, Banner petal narrow or oblanceola te, Banner petal ovoid or obovate, Wing petals narrow, oblanceolate to oblong, Wing tips obtuse or rounded, Keel tips obtuse or rounded, not beaked, Fertile stamens 5, Stamens monadelphous, united below, Filaments glabrous, Style terete, Fruit a legume, Fruit unilocular, Fruit indehiscent, Fruit elongate, straight, Fruit oblong or ellipsoidal, Fruit enclosed in calyx, Fruit glabrous or glabrate, Fruit hairy, Fruit 1-seeded, Seeds reniform, Seeds cordiform, mit-shaped, notched at one end, Seed surface smooth, Seeds olive, brown, or black.

Holotype for Petalostemon standleyanus Rydb.
Catalog Number: US 496689
Collection: Smithsonian Institution, National Museum of Natural History, Department of Botany
Verification Degree: Original publication and alleged type specimen examined
Preparation: Pressed specimen
Collector(s): D. Griffiths
Year Collected: 1903
Locality: Raton Mts., near Colorado-New Mexico Line., New Mexico, United States, North America

More info for the terms: mesic, xeric

Purple prairie clover grows on a variety of sites throughout the Great Plains including dry plains, prairies, hillsides, open woodlands, shaded ravines, sandhills, and roadsides. It occurs on mesic and xeric sites in mixed-grass and tallgrass prairies of the northern and central Great Plains and the shortgrass prairie of the southern Great Plains [24,49,80]. It is most common on marginal sites where soil is exposed and grasses have not formed dense stands [82]. Mean annual precipitation for regions where purple prairie clover subsists ranges from 11 inches (280 mm) in southeast Alberta [32] to 32 inches (810 mm) in Kansas [105] and Oklahoma [13] to 53 inches (1,350 mm) in Mississippi [115].

Soils: Purple prairie clover can be found in most soil types throughout the Great Plains [31]. In the northern Great Plains purple prairie clover is found in sandy to silty loams [17,19]. Some specific soil characteristics have been identified with purple prairie clover in the Nebraska Sandhill prairie region. Here purple prairie clover occurs most frequently in sandy soils that contain medium to coarse grains. It is thought that the coarse sands intercept precipitation with minimal runoff, allowing most of the moisture to reach far below the surface. Due to its taproot morphology, purple prairie clover is able to access moisture from deep in the soil profile and thus is able to persist in areas where other shallow-rooted species cannot [7]. Soils in Minnesota where purple prairie clover is present were found to have pH values of 6.4 to 6.7 [16], with soil depths ranging from 6 to 24 inches (15-6.1 cm) [22].

Elevation: In eastern Colorado purple prairie clover occurs at elevations from 3,500 to 7,500 feet (1,067-2,286 m) [53].

More info for the terms: forb, forbs, mesic, shrubs

Purple prairie clover is an important component of Great Plains grassland
communities. It is considered "common" in most
grassland habitat types of the midwestern United States and southern Canada. Graminoids dominate these regions, comprising 80%
to 90% to the total plant population. Purple prairie clover and other forbs generally make up 10% or less
of total plant population in the Midwest [119]. Purple prairie clover is found in tallgrass, shortgrass, or mixed-grass prairies.
Common associates in tallgrass prairies include little bluestem (Schizachyrium scoparium), big bluestem
(Andropogon gerardii), prairie Junegrass (Koeleria macrantha),
prairie dropseed (Sporobolus heterolepis), lead plant (Amorpha canescens),
and silky aster (Aster sericeus). Associates in mid-grass
prairie include silver bluestem (Bothriochloa saccharoides),
purple threeawn (Aristida purpurea), sideoats grama (Bouteloua curtipendula), and sand dropseed
(Sporobolus cryptandrus). Grass associates in shortgrass prairie include blue grama (Bouteloua gracilis),
hairy grama (B. hirsuta), and buffalo grass (Buchloe
dactyloides). Forb associates include wavyleaf thistle (Cirsium undulatum),
gayfeather (Liatris punctata), and scarlet globemallow (Sphaeralcea
coccinea). Forbs may be interspersed with several shrubs including American hazelnut (Corylus
americana), smooth sumac (Rhus glabra), creeping juniper (Juniperus
horizontalis) and/or trees including green ash (Fraxinus pennsylvanica),
eastern cottonwood (Populus deltoides), eastern redcedar (Juniperus
virginiana), white oak (Quercus alba), bur oak (Q. macrocarpa),
and shagbark hickory (Carya ovata). Woody associates are especially
common near riparian areas and on grassland/forest ecotones in the northern and
eastern fringes of purple prairie clover's distribution [7,8,17,18,19,32,62].

Purple prairie clover also occurs in Nebraska sandhill prairie [7], cedar
glade, limestone glade, dolomite glade [8], dry-mesic savanna, dry-mesic prairie, wet-mesic alluvial floodplain [19], quaking
aspen (Populus
tremuloides)-prairie ecotone [18], and mesic bur
oak (Quercus macrocarpa), black oak (Quercus velutina),
white oak (Quercus alba), and northern pin oak (Quercus
ellipsoidalis) savanna communities [17]. In Illinois, it occurs in dolomite-hill
prairie and "barren" communities [2,19].
In northern Arizona's Grand Canyon National Park,
purple prairie clover is considered an "exotic species,"
and is found in riparian areas of the canyon [95].

More info on this topic.

This species is known to occur in association with the following Rangeland Cover Types (as classified by the Society for Range Management, SRM):

More info for the terms: cover, hardwood, vine

SRM (RANGELAND) COVER TYPES [94]:

301 Bluebunch wheatgrass-blue grama

303 Bluebunch wheatgrass-western wheatgrass

304 Idaho fescue-bluebunch wheatgrass

305 Idaho fescue-Richardson needlegrass

309 Idaho fescue-western wheatgrass

310 Needle-and-thread-blue grama

311 Rough fescue-bluebunch wheatgrass

322 Curlleaf mountain-mahogany-bluebunch wheatgrass

323 Shrubby cinquefoil-rough fescue

502 Grama-galleta

505 Grama-tobosa shrub

601 Bluestem prairie

602 Bluestem-prairie sandreed

603 Prairie sandreed-needlegrass

604 Bluestem-grama prairie

605 Sandsage prairie

606 Wheatgrass-bluestem-needlegrass

607 Wheatgrass-needlegrass

608 Wheatgrass-grama-needlegrass

609 Wheatgrass-grama

610 Wheatgrass

611 Blue grama-buffalo grass

612 Sagebrush-grass

613 Fescue grassland

614 Crested wheatgrass

615 Wheatgrass-saltgrass-grama

701 Alkali sacaton-tobosagrass

702 Black grama-alkali sacaton

703 Black grama-sideoats grama

704 Blue grama-western wheatgrass

705 Blue grama-galleta

706 Blue grama-sideoats grama

707 Blue grama-sideoats grama-black grama

708 Bluestem-dropseed

709 Bluestem-grama

710 Bluestem prairie

711 Bluestem-sacahuista prairie

712 Galleta-alkali sacaton

713 Grama-muhly-threeawn

714 Grama-bluestem

715 Grama-buffalo grass

716 Grama-feathergrass

717 Little bluestem-Indiangrass-Texas wintergrass

718 Mesquite-grama

719 Mesquite-liveoak-seacoast bluestem

720 Sand bluestem-little bluestem (dunes)

721 Sand bluestem-little bluestem (plains)

722 Sand sagebrush-mixed prairie

724 Sideoats grama-New Mexico feathergrass-winterfat

725 Vine mesquite-alkali sacaton

727 Mesquite-buffalo grass

728 Mesquite-granjeno-acacia

729 Mesquite

730 Sand shinnery oak

731 Cross timbers-Oklahoma

732 Cross timbers-Texas (little bluestem-post oak)

733 Juniper-oak

734 Mesquite-oak

735 Sideoats grama-sumac-juniper

801 Savanna

802 Missouri prairie

803 Missouri glades

804 Tall fescue

805 Riparian

809 Mixed hardwood and pine

More info on this topic.

This species is known to occur in association with the following cover types (as classified by the Society of American Foresters):

More info for the terms: cover, swamp

SAF COVER TYPES [41]:


14 Northern pin oak

15 Red pine

16 Aspen

20 White pine-northern red oak-red maple

25 Sugar maple-beech-yellow birch

26 Sugar maple-basswood

27 Sugar maple

28 Black cherry-maple

39 Black ash-American elm-red maple

40 Post oak-blackjack oak

42 Bur oak

46 Eastern redcedar

51 White pine-chestnut oak

52 White oak-black oak-northern red oak

53 White oak

55 Northern red oak

57 Yellow-poplar

58 Yellow-poplar-eastern hemlock

59 Yellow-poplar-white oak-northern red oak

61 River birch-sycamore

62 Silver maple-American elm

63 Cottonwood

64 Sassafras-persimmon

65 Pin oak-sweetgum

66 Ashe juniper-redberry (Pinchot) juniper

67 Mohrs (shin) oak

68 Mesquite

73 Southern redcedar

87 Sweetgum-yellow-poplar

88 Willow oak-water oak-diamondleaf (laurel) oak

89 Live oak

91 Swamp chestnut oak-cherrybark oak

92 Sweetgum-willow oak

93 Sugarberry-American elm-green ash

94 Sycamore-sweetgum-American elm

108 Red maple

109 Hawthorn

110 Black oak

235 Cottonwood-willow

236 Bur oak

237 Interior ponderosa pine

241 Western live oak

242 Mesquite

More info on this topic.

This species is known to occur in association with the following plant community types (as classified by Küchler 1964):

More info for the term: shrub

KUCHLER [68] PLANT ASSOCIATIONS:

K016 Eastern ponderosa forest

K017 Black Hills pine forest

K018 Pine-Douglas-fir forest

K019 Arizona pine forest

K023 Juniper-pinyon woodland

K053 Grama-galleta steppe

K056 Wheatgrass-needlegrass shrubsteppe

K058 Grama-tobosa shrubsteppe

K059 Trans-Pecos shrub savanna

K060 Mesquite savanna

K061 Mesquite-acacia savanna

K062 Mesquite-live oak savanna

K063 Foothills prairie

K064 Grama-needlegrass-wheatgrass

K065 Grama-buffalo grass

K066 Wheatgrass-needlegrass

K067 Wheatgrass-bluestem-needlegrass

K068 Wheatgrass-grama-buffalo grass

K069 Bluestem-grama prairie

K070 Sandsage-bluestem prairie

K071 Shinnery

K073 Northern cordgrass prairie

K074 Bluestem prairie

K075 Nebraska Sandhills prairie

K076 Blackland prairie

K081 Oak savanna

K082 Mosaic of K074 and K100

K083 Cedar glades

K084 Cross Timbers

K085 Mesquite-buffalo grass

K086 Juniper-oak savanna

K087 Mesquite-oak savanna

K088 Fayette prairie

K089 Black Belt

K095 Great Lakes pine forest

K098 Northern floodplain forest

K099 Maple-basswood forest

K100 Oak-hickory forest

K101 Elm-ash forest

K102 Beech-maple forest

K111 Oak-hickory-pine

More info on this topic.

This species is known to occur in the following ecosystem types (as named by the U.S. Forest Service in their Forest and Range Ecosystem [FRES] Type classification):

ECOSYSTEMS [44]:

FRES10 White-red-jack pine

FRES14 Oak-pine

FRES15 Oak-hickory

FRES17 Elm-ash-cottonwood

FRES19 Aspen-birch

FRES21 Ponderosa pine

FRES29 Sagebrush

FRES31 Shinnery

FRES32 Texas savanna

FRES33 Southwestern shrubsteppe

FRES36 Mountain grasslands

FRES38 Plains grasslands

FRES39 Prairie

Purple Prairie Clover occurs occasionally in central and northern Illinois, but is rare or absent in southern Illinois (see Distribution Map). It is not common in areas that have been disturbed by modern development. Habitats include mesic to dry black soil prairies, gravel prairies, sand prairies, hill prairies, typical savannas and sandy savannas, limestone glades, and sandy hills or dunes near Lake Michigan. Recovery from occasional wildfires is good. Faunal Associations

This species is easily established from seed and the seed is commercially available through plant vendors. Germination of this species is rather poor without some type of scarification procedure. Mechanical scarification using sandpaper or a laboratory scarifier is acceptable. Purple prairie clover should be planted on a prepared, weed free, firm seedbed. The seedbed should be firm enough to allow planting at a 6 to 12 mm depth. Seed should be inoculated with the proper Rhizobium (Nitragin-type F) strain prior to planting.

Planting using a drill with depth bands and a legume box would provide good seed depth placement and seed to soil contact. The use of broadcast seeding will require a greater overall seeding rate to compensate for a less accurate delivery system. A normal seeding rate of 323 to 388 PLS seeds per square meter would have to be increased to accommodate a broadcast seeding.

Fischbach et al. (2005) found that in Minnesota in a seeding rate experiment that purple prairie clover had increased number of seedlings the year after establishment at all seeding rate levels tested. All legumes in the test had the highest percentage of seeds that develop into plants at the lowest seeding rate and the lowest seeds that develop into plants at the highest seeding rate. Launchbaugh and Owensby (1970), working with several native grass species, also noticed an inverse relationship between increased seeding rates and final plant establishment.

Dalea purpurea (Purple Prairie Clover)
(Bees collect pollen or suck nectar; flies and beetles usually suck nectar, although some species may feed on pollen; other insects suck nectar; observations are from Petersen, Moure & Hurd, and Reed as indicated below, otherwise they are from Robertson)

Bees (long-tongued)
Apidae (Apinae): Apis mellifera sn cp fq; Apidae (Bombini): Bombus affinis (Re), Bombus auricomus sn cp (Rb, Re), Bombus bimaculatus (Re), Bombus fervida (Pt, Re), Bombus fraternus sn cp fq, Bombus griseocallis sn cp fq (Rb, Re), Bombus impatiens sn cp fq (Rb, Re), Bombus pensylvanica sn cp fq (Rb, Re), Bombus ternarius (Re), Bombus vagans (Re), Psithyrus variabilis sn; Anthophoridae (Anthophorini): Anthophora walshii sn; Anthophoridae (Ceratinini): Ceratina dupla dupla sn cp; Anthophoridae (Epeolini): Epeolus bifasciatus sn, Triepeolus concavus sn fq, Triepeolus lunatus concolor sn fq, Triepeolus lunatus lunatus sn, Triepeolus remigatus sn; Anthophoridae (Eucerini): Melissodes agilis sn (Rb, Re), Melissodes bimaculata bimaculata sn cp fq (Rb, Re), Melissodes communis sn cp fq, Melissodes comptoides sn fq, Melissodes denticulata sn, Melissodes illata (Re), Melissodes tepaneca sn cp fq, Melissodes trinodis sn, Svastra obliqua obliqua sn cp fq, Synhalonia speciosa sn cp, Tetraloniella albata sn; Anthophoridae (Xylocopini): Xylocopa virginica sn; Megachilidae (Coelioxini): Coelioxys alternata alternata sn, Coelioxys germana sn, Coelioxys octodentata sn fq, Coelioxys rufitarsis rufitarsis sn (Rb, Re), Coelioxys sayi sn; Megachilidae (Megachilini): Megachile brevis brevis sn cp fq, Megachile inimica sayi sn, Megachile latimanus sn cp fq (Rb, Re), Megachile parallela parallela sn; Megachilidae (Osmiini): Hoplitis cylindricus sn cp fq, Hoplitis pilosifrons sn cp; Megachilidae (Trypetini): Heriades leavitti sn cp

Bees (short-tongued)
Halictidae (Halictinae): Agapostemon sericea sn (Rb, Re), Agapostemon splendens sn (Rb, Re), Agapostemon texanus texanus sn (Rb, Re), Agapostemon virescens sn cp fq (Rb, Re), Augochlorella aurata sn cp fq, Augochlorella striata sn cp fq (Rb, Re), Augochloropsis metallica metallica sn cp fq (Rb, Re), Halictus confusus sn cp fq (Rb, Re), Halictus ligatus sn cp, Halictus parallelus sn cp fq (Rb, MH), Halictus rubicunda sn cp fq (Rb, Pt), Lasioglossum sp. (Re), Lasioglossum albipennis cp fq (Rb, Re), Lasioglossum cressonii (Re), Lasioglossum lineatulus (Re), Lasioglossum nymphaearum (Re), Lasioglossum paradmirandus (Re), Lasioglossum perpunctatus (Re), Lasioglossum pictus (Re), Lasioglossum pilosus pilosus sn cp (Rb, Re), Lasioglossum pruinosus sn, Lasioglossum rohweri (Re), Lasioglossum tegularis (Re), Lasioglossum versatus sn cp fq, Lasioglossum vierecki (Re); Halictidae (Nomiinae): Nomia nortoni nortoni sn; Colletidae (Colletinae): Colletes aberrans (Re), Colletes albescens sn cp olg, Colletes robertsonii sn cp olg, Colletes susannae cp olg (Re), Colletes wilmattae cp olg (Re); Colletidae (Hylaeinae): Hylaeus affinis (Re); Andrenidae (Andreninae): Andrena commoda (Re)

Wasps
Sphecidae (Bembicinae): Bembix americana, Bembix nubilipennis, Bembix sayi (Re); Sphecidae (Philanthinae): Cerceris bicornuta, Philanthus sanbornii (Re), Philanthus ventilabris (Rb, Re); Sphecidae (Sphecinae): Ammophila kennedyi, Ammophila nigricans fq, Ammophila pictipennis, Ammophila procera, Eremnophila aureonotata, Prionyx atrata (Rb, Re), Prionyx thomae, Sphex ichneumonea; Vespidae (Eumeninae): Eumenes fraterna; Tiphiidae: Myzinum quinquecincta fq (Rb, Re); Scoliidae: Campsomeris plumipes

Flies
Syrphidae: Allograpta obliqua sn, Eristalis stipator sn, Eristalis tenax (Re), Eupeodes sp. (Re), Helophilus latifrons sn (Rb, Re), Neocnemodon sp. (Re), Sphaerophoria contiqua sn (Rb, Re), Syrphus sp. (Re), Toxomerus geminatus (Re), Toxomerus marginatus sn (Rb, Re), Tropidia quadrata sn; Bombyliidae: Exoprosopa fasciata sn, Systoechus vulgaris sn, Villa sp. (Re); Conopidae: Physocephala texana sn, Thecophora occidensis sn, Zodion obliquefasciatum sn; Sarcophagidae: Ravinia anxia sn

Butterflies
Lycaenidae: Everes comyntas; Pieridae: Colias cesonia, Colias philodice

Skippers
Hesperiidae: Pholisora catullus, Polites peckius, Polites themistocles

Beetles
Cerambycidae: Typocerus sinuatus sn; Chrysomelidae: Diabrotica sp. (Re), Diabrotica undecimpunctata sn; Meloidae: Epicauta atrata sn, Epicauta pensylvanica sn

Plant Bugs
Miridae: Adelphocoris rapidus; Pentatomidae: Euschistus ictericus

More info for the terms: forbs, headfire, interference, severity

Fire severity affects purple prairie clover survivorship and postfire productivity. Bidwell and others [12,13] noted the effects of using a backing fire versus a headfire. In postfire year 1, abundance of forbs (including purple prairie clover) was 26% greater on backfired plots compared to headfired plots. This may be due to a reduction in interference from tallgrasses, such as prairie Junegrass and little bluestem, which are negatively affected by late spring burning. Also, backfires often create a mosaic of burned and unburned patches that may provide favorable microsites where purple prairie clover can escape lethal fire temperatures [13].

More info for the terms: competition, forbs

Annual burning of prairie lands reduces available soil nitrogen
and increases competition among plants limited by nitrogen availability [78]. Legumes including
purple prairie clover have the ability to fix
atmospheric nitrogen, and may have an advantage over other forbs and some grasses
in nitrogen-stressed environments [69].

More info for the terms: cover, fire management, forb, forbs, frequency, litter, long-term effects, natural, phenology, prescribed burn, prescribed fire, presence, restoration, root crown

Plant growth: Purple prairie clover may recover from fire by establishing from soil-stored seed and sprouting from the root crown. Purple prairie clover has responded favorably to prescribed fire in various studies [12,13,39,64]. Due to the hard seedcoat of legumes like purple prairie clover, these species' germination rates maybe enhanced by burning [70].

Towne and Knapp [104] noted that purple prairie clover that was top-killed by fire showed great capacity to sprout after fire. There is no specific information available on how quickly purple prairie clover recovers after burning. Further research is needed on this topic.

Productivity: Several studies have focused on how the frequency of burning relates to productivity of purple prairie clover. Generally, annual burning favors annual grasses and reduces the abundance of perennial forbs including purple prairie clover [66]. Studies conducted in Minnesota in 1984 [101] and Missouri in 1964 [66] suggest that, compared to annual burning, biennial burning increases frequency and basal areas of legume species [66] including purple prairie clover [101]. In Wisconsin prairie restoration projects where purple prairie clover has prospered, managers recommend a 5-year burning interval [21].

Burning can enhance flower productivity in several prairie forbs including purple prairie clover. Purple prairie clover produced a greater abundance of inflorescences after a single spring burn on a Minnesota prairie than prior to burning [80]. The effects of this burn are attributed to the removal of litter and standing dead stems by the fire. Removal of litter allows for increased light intensities near the soil and thus higher soil temperatures, which enhance plant productivity. Litter reduces the presence and productivity of many forbs including purple prairie clover [39]. For more on the effects of litter on purple prairie clover, see Management Considerations.

The Great Plains region where purple prairie clover commonly occurs is typical of prairie and savanna ecosystems that require fire to maintain historical ranges of species composition and species richness [30]. Most of the available information has been based on short-term research [58]. Long-term effects (beyond the scope of current research; >20 years) of various FIRE REGIMES are not well known.

Season of burning: Interactions between season of burn and purple prairie clover phenology are not well known [60]. While spring burning generally decreases the immediate abundance of forb species that are actively growing [2], legume species including purple prairie clover in Kansas have shown increased growth and vigor 3 years following spring burns, nearly doubling stem biomass on upland sites and quadrupling stem biomass on lowland sites [104].

While most studies find that forb production is compromised after late spring burning, Bidwell and others [12,13] found that late spring backburning increased the productivity of purple prairie clover and other forb species (see Fire Management Considerations). Testing seasonal differences in annual prescribed annual burning on a Kansas prairie for 8 years, Towne and Kemp [103] found that legume species including purple prairie clover increased in cover in response to burning at any season. Greatest increases occurred 6 years after fire treatments, on autumn and winter prescribed burn plots. Others have found that most forbs including purple prairie clover decrease in abundance after being top-killed by late spring burning, while purple prairie clover increases after autumn and early spring burning [46,87].

The effects of  mid-summer burning are not available in current literature (2005). For the purposes of restoration ecology, dormant-season fires probably do not resemble historical disturbance regimes found before European settlement. It is suspected that varied burn seasons, and intervals brought by natural ignitions from lightning prior to the European settlement era, produced greater levels of biodiversity and species assemblages than any single management method for native prairie lands [60]. Unfortunately, information on purple prairie clover frequency and abundance prior to European settlement is not available.

Purple prairie clover is top-killed by fire [104].

More info for the terms: ground residual colonizer, root crown

POSTFIRE REGENERATION STRATEGY [97]:
Caudex/herbaceous root crown, growing points in soil
Ground residual colonizer (on-site, initial community)

More info for the terms: interference, natural, prescribed fire, root crown

Fire adaptations: Purple prairie clover establishes from soil-stored seed after fire. While not specifically documented, it is implied that purple prairie clover root crowns may survive burning that consumes the aerial portions of the plant, allowing postfire sprouting from the root crowns [104]. The large woody taproot allows for photosynthate and nutrient storage that can support postfire root crown sprouting. Additionally, fire creates favorable conditions (disturbed soil, decreased levels of mulch, reduced interference from forbs) that are favorable for purple prairie clover seedling establishment and growth [12,13,39,64].

FIRE REGIMES: Historically fire has been an important natural component of grassland communities where purple prairie clover occurs [35]. Frequent, stand-replacement surface fires in plains grasslands and prairies affect species composition and vegetation dynamics [79]. Across the Great Plains, lightning-caused and human-caused fires may have occurred as frequently as every 1 to 10 years for thousands of years prior to European settlement [67,117]. The implications of the cessation of historical FIRE REGIMES in the last century on purple prairie clover are unknown. Purple prairie clover has responded favorably to burning in several prescribed fire studies [12,13,39,64] using various annual intervals and seasons (see Plant Response to Fire).

In some habitats fire is necessary to maintain purple prairie clover. For example, along woodland-grassland ecotones in purple prairie clover's eastern range, the cessation of fire has caused encroachment of woody species that shade out purple prairie clover and reduce its abundance [45].

The following list provides fire return intervals for plant communities and ecosystems where purple prairie clover is important. It may not be inclusive. For further information see the FEIS reviews on the dominant species listed below.

Community or Ecosystem	Dominant Species	Fire Return Interval Range (years)
sugar maple-basswood	Acer saccharum-Tilia americana	> 1,000 [109]
bluestem prairie	Andropogon gerardii var. gerardii-Schizachyrium scoparium	67,79]
Nebraska sandhills prairie	A. gerardii var. paucipilus-S. scoparium	< 10
bluestem-Sacahuista prairie	A. littoralis-Spartina spartinae	79]
silver sagebrush steppe	Artemisia cana	5-45 [56,85,117]
sagebrush steppe	A. tridentata/Pseudoroegneria spicata	20-70 [79]
basin big sagebrush	A. tridentata var. tridentata	12-43 [89]
mountain big sagebrush	A. tridentata var. vaseyana	15-40 [5,23,75]
Wyoming big sagebrush	A. tridentata var. wyomingensis	10-70 (40**) [107,118]
plains grasslands	Bouteloua spp.	79,117]
blue grama-needle-and-thread grass-western wheatgrass	B. gracilis-Hesperostipa comata-Pascopyrum smithii	79,88,117]
blue grama-buffalo grass	B. gracilis-Buchloe dactyloides	79,117]
blue grama-tobosa prairie	Bouteloua gracilis-Pleuraphis mutica	79]
cheatgrass	Bromus tectorum	81,114]
sugarberry-America elm-green ash	Celtis laevigata-Ulmus americana-Fraxinus pennsylvanica	109]
northern cordgrass prairie	Distichlis spicata-Spartina spp.	1-3 [79]
black ash	Fraxinus nigra	109]
Ashe juniper	Juniperus ashei	79]
cedar glades	J. virginiana	3-22 [52,79]
yellow-poplar	Liriodendron tulipifera	109]
wheatgrass plains grasslands	Pascopyrum smithii	79,85,117]
pine-cypress forest	Pinus-Cupressus spp.	4]
sycamore-sweetgum-American elm	Platanus occidentalis-Liquidambar styraciflua-Ulmus americana	109]
eastern cottonwood	Populus deltoides	79]
aspen-birch	P. tremuloides-Betula papyrifera	35-200 [38,109]
quaking aspen (west of the Great Plains)	P. tremuloides	7-120 [4,50,73]
mesquite	Prosopis glandulosa	71,79]
Texas savanna	P. glandulosa var. glandulosa	79]
black cherry-sugar maple	Prunus serotina-Acer saccharum	> 1,000 [109]
mountain grasslands	Pseudoroegneria spicata	3-40 (10**) [3,4]
bur oak	Quercus macrocarpa	109]
oak savanna	Q. macrocarpa/Andropogon gerardii-S. scoparium	2-14 [79,109]
shinnery	Q. mohriana	79]
Fayette prairie	S. scoparium-Buchloe dactyloides	109]
little bluestem-grama prairie	S. scoparium-Bouteloua spp.	79]
elm-ash-cottonwood	Ulmus-Fraxinus-Populus spp.	38,109]

**mean

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More info for the terms: forbs, natural, sere, succession

Generally purple prairie clover is considered a mid- to late successional species [102]. Purple prairie clover can also fill a pioneer role, as seen in roadsides and disturbed locations [91]. The following is a general description of the successional pathways on prairie lands. Many details of succession in these associations remain unknown.

On the mixed-grass prairies of the southern Great Plains, purple prairie clover is part of a group of forbs found in late successional seres. A common pattern of succession in disturbed prairie regions begins with the dominance of native prairie annuals, nonnative annual weeds, and ragweeds (Ambrosia spp.), which may persist for 1 to 3 years. Soon following, a collection of nonnative and native grasses and perennial forbs, including purple prairie clover, create a mosaic of species that may take 15 to 40 years to develop, depending on environmental conditions and "competitive" factors. Common species that coexist with purple prairie clover in the tallgrass prairie during the later stages of succession include lead plant and prairie dropseed [91].

In its eastern range in forest openings where fires and other natural disturbances are suppressed, purple prairie clover can be shaded out by encroaching woody species [55]. Purple prairie clover is thought to be an indicator of prairie in its later successional sere and may be an indicator of pristine prairie ecosystems [91].

More info for the terms: duff, forb, forbs, litter, prescribed fire, reclamation, root crown, top-kill

Purple prairie clover reproduces by seed [16].

Breeding system: Purple prairie clover is cross pollinated [16]. Mating system is primarily xenogamous, but self-pollination also occurs. In a Wisconsin prairie study, 45% of hand-pollinated, outcrossed flowers produced large, viable seeds, and 19% of selfed flowers produced seeds. Native bees and honeybees were pollinators [27].

Pollination is insect-mediated [16,27].

Seed production is highest with favorable soil moisture and nutrient conditions. A survey of native plant horticulturists in Minnesota indicated that purple prairie clover frequently produces low seed yields [15]. Another Minnesota study compared the phenological development of purple prairie clover in cultivated fields to noncultivated managed prairie. Cultivated fields produced 3 times as much seed as noncultivated prairie. Seed and inflorescence production on cultivated and noncultivated native prairie were [16]:

Item	Cultivated Fields	Noncultivated Prairie
Number of inflorescences initiated/plant	35.0	29.1
Weight/inflorescence (g)	0.36	0.25
Seed weight/inflorescence	0.043	0.015
Number of seeds/inflorescence	33.5	11.5
Seed weight/plant (g)	0.49	0.22
Number of seeds/plant	379.8	173.4

Cultivated fields were devoid of any other competing plants, fertilized, and only contained evenly spaced transplanted purple prairie clover plants from native prairie lands. The noncultivated, native prairie had a variety of other forb and grass species. The noncultivated prairie was under a regimen of prescribed fire every 2 to 3 years. Season of burning was not described [16]. Stevens [96] found that a single purple prairie clover plant may produce 368 seeds per plant (many of which may not mature), with seeds weighing 1.5 g/1,000 seeds.

Seed dispersal: Neither fruits nor seeds have specialized means of dispersal; thus, most seed falls near the parent plant [110].  A seed dispersal study using purple prairie clover and other seed in cattle feed showed that following ingestion, cattle were inefficient vectors for dispersing viable purple prairie clover seed [37].

Seed banking: Purple prairie clover has soil-stored seed [110], but further studies are needed on the relative importance of seed banking to purple prairie clover regeneration. A study on native Kansas prairie found low numbers of buried viable purple prairie clover seed [1].

Germination: Purple prairie clover germinates at soil temperatures ranging from 59 to 86 °F (15-30 °C) [9] while temperatures as low as 41 °F (5 °C) have broken dormancy [14].  A survey of native plant horticulture in Minnesota indicated low rates of germination of purple prairie clover [16].  Germination of purple prairie clover is enhanced by scarification, disturbing the litter and duff layers to expose soil, and stratification [14,100].

Seedling establishment/growth: Bjugstand and Whitman [14] used several varieties of forbs for reclamation of strip-mined land and found that purple prairie clover showed "excellent" germination and subsequent "vigorous" growth in the greenhouse. Purple prairie clover transplanted to reclamation areas continued to show excellent vigor and growth [14].

Asexual regeneration: The ability of purple prairie clover to regenerate vegetatively is unclear. Meier and Weaver [72] state that purple prairie clover does not reproduce asexually. However, Towne and Knapp [104] suggest that purple prairie clover sprouts from the root crown following top-kill by fire. Further research is needed on the ability of purple prairie clover to regenerate asexually.

More info on this topic.

More info for the term: hemicryptophyte

RAUNKIAER [86] LIFE FORM:
Hemicryptophyte

More info for the term: forb

Forb

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More info for the terms: forb, warm-season

Purple prairie clover is a warm-season forb that generally germinates during spring [84]. In May to August (depending on climate and geographic location), purple prairie clover produces several to many inflorescences. Average flowering dates for purple prairie clover from 5 years of observation in North Dakota were [99]:

Earliest 1st bloom	Latest 1st bloom	Median date of full flowering	Median date when 95% of flowering complete	Flowering period (days)
June 17th	July 13th	July 15th	August 15th	35

Flowering dates for purple prairie clover are influenced more by temperature than precipitation. Warmer temperatures seem to promote earlier flowering, while warm temperatures and ample moisture in summer increase the duration of blooming [26]. Purple prairie clover seed matures in most locations from August to September [9]. In Minnesota seed development from anthesis to seed maturity took 15 weeks [16].

The following is a representative barcode sequence, the centroid of all available sequences for this species.


No available public DNA sequences.

Download FASTA File

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 3
Specimens with Barcodes: 7
Species With Barcodes: 1

Purple prairie clover is globally ranked as G5: demonstrably secure [74]. State rankings are as follows [106]:

Location	Rank
Kentucky	Special Concern
Michigan	Probably Extirpated
Ohio	Presumed Extirpated
Tennessee	Endangered

Canada

Rounded National Status Rank: NNR - Unranked

United States

Rounded National Status Rank: N5 - Secure

Rounded Global Status Rank: G5 - Secure

Please consult the PLANTS Web site and your State Department of Natural Resources for this plant’s current status (e.g. threatened or endangered species, state noxious status, and wetland indicator values).

Grasshoppers and small rodents in moderate numbers can cause damage to seedling stands.

More info for the terms: cover, density, forb, forbs, frequency, litter, prescribed fire

Low- to moderate grazing pressure may enhance purple prairie clover production
by removing vegetative cover [18], but overgrazing can decrease coverage and frequency of purple prairie
clover [49]. In Illinois, populations of purple prairie clover have recovered in areas where
they had been removed
under high grazing pressure [19]. In Iowa, purple
prairie clover
was 1 species in a large group of native forbs that decreased or disappeared
under unspecified grazing pressure [111].

In prairies near forest lands, encroachment of forest species
into grasslands changes vegetation structure and composition. In eastern Nebraska, eastern redcedar encroachment
into prairies has been linked to the decline of many prairie species, including
purple prairie clover, due to shading [45].
The accumulation of litter on prairies affects purple
prairie clover
populations. In Kansas, purple prairie clover decreased during a 50-year study on
tallgrass prairie that has seen a shift
from summer haying to spring biannual burning. The author speculates that these
decreases resulted from the cessation of mid-summer
mowing. In this study mowing was thought to be responsible for the removal
of biomass during the summer months, altering microhabitat conditions that had
supported purple prairie clover. The
increase of mulch thickness may explain decreases in purple
prairie clover and
other native forbs [36]. In a study of the effects of cessation of mowing and
introduction of prescribed fire, forbs including purple prairie
clover increased in abundance due to the reduction of mulch [29]. For more on the effects of litter on purple prairie clover,
see Fire Effects
Experimental research on effects of small rodent herbivory on native forb populations
found that herbivory by meadow voles reduced  purple prairie clover density [59,77]. Whether or not
these findings in laboratory communities were applicable to prairie
communities was unclear.

Contact your local Natural Resources Conservation Service office for more information. Look in the phone book under ”United States Government.” The Natural Resources Conservation Service will be listed under the subheading “Department of Agriculture.”

‘Kaneb’ purple prairie clover was released by the Manhattan, Kansas Plant Materials Center in 1975 in cooperation with the Nebraska Agriculture Experiment Station in Lincoln, Nebraska. It was first collected in 1948 in a native grassland area in Riley County, Kansas. Testing indicated it was superior in stand, height and vigor to other collected accessions. This accession was also grown and tested at SCS Plant Materials Center’s in North Dakota and New Mexico. Foundation seed is maintained by the Manhattan Plant Materials Center.

Bismarck Germplasm is a selected class release from the Bismarck, North Dakota Plant Materials Center. It was collected originally in 1975 in Lyman County, South Dakota by Tom Pozarnsky. Bismarck was compared to ten purple prairie clover accessions and was selected for its superior vigor, forage abundance and above average seed yield. Generation 1 seed is maintained by the Bismarck Plant Materials Center and is available in limited quantities for commercial seed increase.

Central Iowa Germplasm is a source identified release from the Elsberry, Missouri Plant Materials Center. It is a composite of collections of purple prairie clover made through out central Iowa. Breeder’s seed is maintained by the Elsberry Plant Materials Center and the University of Northern Iowa (UNI) at Cedar falls, Iowa. Source identified seed will be available to interested seed producers.

McGraw et al. (2004) determined seed production potential by measuring the weight of seeds per plant and the number of seeds per plant. Purple prairie clover which produced only 2.1 g of seed per plant, produced as many seeds per plant as the top three legumes due to its relatively smaller seed size. Purple prairie clover averaged 698 seed per gram which yields 698,000 seeds per kilogram which would be 317,000 seeds per pound for this species. Seed can be collected by hand stripping pods from mature plants and then hammer milling and re-cleaning in a fanning mill. Field size stands can be harvested with a standard combine and then cleaned in a fanning mill.

Five year average seed yields at Manhattan Plant Materials Center (PMC) were 136.5 kg per hectare. Purity of harvested, processed seed is typically 99 percent or better with a germination range of 36 to 83 percent (including germination and hard seed). A long term seed storage study conducted by the Manhattan PMC indicates that ‘Kaneb’ purple prairie clover can be stored successfully under ideal (cool and dry) conditions for up to 26 years and retain good germination. Kaneb’s initial germination was 81 percent and after 26 years of storage the germination result was still 77 percent. There was however, a much lower percentage of hard seed in the latest test results when compared to the initial test results.

Purple prairie clover does not spread aggressively by seed or vegetatively (Platt and Harder 1991).

Weed control during establishment of native forbs is essential to produce healthy plant stands. Mowing at a height that will not affect purple prairie clover seedlings is one method of reducing weed competition. Masters et al. (1996) found that the use of Imidazolinone herbicides was successfully used to establish purple prairie clover. Irrigated and non-irrigated plots of purple prairie clover experienced greater foliar cover when treated with herbicides when compared to non-herbicide treated plots (Masters et al. 1996).

McGraw et al. (2004) found that while purple prairie clover tended to have good forage quality, it had relatively poor forage yields when compared to other native legumes. Posler et al. (1993) found that the influence of purple prairie clover was positive on forage digestibility when compared to values for grasses alone. They concluded that the use of mixtures of purple prairie clover with adapted warm-season grasses as forage crops appeared promising.

More info for the terms: forbs, interference, invasive species, natural, reclamation, restoration

Purple prairie clover is commonly found in seed mixtures recommended for revegetation, reclamation [34,93], and native prairie restoration projects [65]. Gustafson and others [51] found that by using several local seed sources of purple prairie clover for restoration projects, local gene pools were maintained and regional genetic diversity was enhanced, promoting persistence and vigor in restored purple prairie clover populations. Purple prairie clover is frequently used in seed mixes for erosion control due to its ability to establish on disturbed sites and its capability to condition soil with nitrogen [92]. Legumes such as purple prairie clover fix atmospheric nitrogen in the soil. They may have an advantage over forbs and some grasses in degraded prairie or pasture sites [24,62].

Propagation: Purple prairie clover germination is enhanced in scarified soils [100]. Purple prairie clover in its natural habitat is often found in disturbed locations such as black-tailed prairie dog towns [98] and on dug mounds created by American badgers [83]. Stratification [100] and inoculation with rhizobium [65] have increased germination success of purple prairie clover in the laboratory. Purple prairie clover has been successfully used in several roadside vegetation projects throughout the Great Plains [28,33]. In a strip-mine reclamation project, purple prairie clover demonstrated excellent success as a colonizer, exhibiting high rates of germination and subsequent vigorous seedling growth in the greenhouse and afterwards during transplanting [14].

Purple prairie clover is highly dependent upon mycorrhizal fungi. A mycorrhizal inoculation study found prairie species uptake and transport of soil nutrients such as phosphorus and zinc was enhanced by mycorrhizae, but the study did not show any substantial effects on purple prairie clover seedling emergence  [54]. Conversely, a study that used a benomyl (a fungicide specifically for the removal of mycorrhizae in soils) considerably lowered survivorship of purple prairie clover [116].

Purple prairie clover is susceptible to interference from with exotic species during establishment due to its relatively slow rate of seedling growth compared to that of nonnative invasive species. In North Dakota some populations of purple prairie clover have been completely eliminated by infestations of leafy spurge (Euphorbia esula) [25]. Reducing weed interference using herbicide applications (imazethapyr + imazapic) has been successful in improving establishment of purple prairie clover in Nebraska [10].

More info for the terms: cover, restoration

Purple prairie clover produces excellent forage for livestock and wildlife. When abundant on pasture lands it may be an important component in hay [62,100]. Purple prairie clover is recommended for use in restoration seed mixtures. It produces forage with high yields, extended grazing periods, and increased nutritional values [84,90]. Pronghorn graze purple prairie clover on summer ranges of Montana [113]. A 2-year study in Minnesota found that white-tailed deer did  not browse purple prairie clover [40], although this does not imply that deer and other ungulates never graze this species.

Palatability/nutritional value:
In North Dakota, crude protein levels of purple prairie clover ranged from 12% in June to 8% in August [84]. Due to its high palatability and high concentrations of nutritional protein, purple prairie clover is generally considered one of the most important legumes in native grasslands on the Great Plains, although some rare instances of bloat have been reported in livestock [62,100]. Crude and digestible protein content of purple prairie clover are as follows [76]:

Crude Protein	14.1%
Digestible Protein
cattle	9.9 %
domestic goats	9.7 %
domestic rabbits	9.6 %
domestic sheep	10.1 %
horses	9.5 %

Cover value: No information is available on this topic.

Native Americans boiled purple prairie clover leaves for food. The Ponca tribe chewed the roots for their pleasant flavor and made tea from leaves. The Pawnee used the stems to make brooms.  Native American used boiled leaves to make a poultice for dressing on wounds [47]. Laboratory studies have found antibacterial and fungicidal compounds in purple prairie clover [61].

This leguminous forb produces excellent forage for livestock and wildlife. It is high in protein and highly palatable, although it may cause bloat. (Stubbedieck and Conard 1989) This species will decrease and disappear under persistent overgrazing. It is an important legume in native grasslands because of nitrogen fixation. Purple prairie clover is used in seed mixtures for re-vegetation and prairie restoration. It is a potentially useful plant for roadside and rest area beautification, park plantings and recreational garden natural area plantings. This species is also used in mixtures on dam face structures and critical area plantings. Native Americans ate fresh and boiled leaves of purple prairie clover. Bruised leaves were steeped in water and applied to fresh, open wounds. Ponca Indians chewed the roots for their pleasant flavor and made tea from the leaves. Pawnee Indians used the bundled stems to make brooms. (Stubbendieck et al. 1989).