This description covers characteristics that may be relevant to fire ecology and is not meant for identification. Keys for identification are available (for example, [10,38,48,84,117,138]).
Leadplant is a low, spreading [36] subshrub [38,123,132], with semiwoody stems [65]. Stems are single or clustered at the woody root crown [114]. They are erect and/or ascending [128]. Mature plants may reach 1.0 to 3.5 feet (0.3-1.1 m) tall [38,128]. Leadplant is sometimes termed a forb because on sites that are regularly burned, mowed, or heavily grazed, it remains short and its stems remain mostly herbaceous due to frequent top-kill [62,117,118,134,136]; however, its root crown remains woody [62]. This species is called leadplant due to its leaves, which are a leaden gray-green and covered with fine hairs. Leaves are compound. The inflorescences are several [114], arranged in densely clustered racemes [10,38,128]. There may be 200 to 300 flowers/raceme [147]. The fruit is a hairy [117], indehiscent [147] legume [48,117,128]. The seeds are solitary in the pod [14,114,118,128] and small, about 2 mm long [10,128,128]. Leadplant is generally rhizomatous [38,48,147], although this may not be true of all plants [48]. Leadplant has a taproot [119,147] and secondary lateral and vertical roots [147]. Roots are branched [14] and typically deeper than those of associated bunchgrasses [62,136]. They may penetrate 7 to 20 feet (2-5 m), depending on the soil [10]. Weaver [133,136] excavated leadplant roots from depths of 6 to 16 feet (2-5 m) in tallgrass prairies. A 7-year-old plant had 11 primary vertical and horizontal roots that extended 4 to 5 feet (1-1.5 m) from the root crown. Some secondary roots extended 16.5 feet [133]. Leadplant roots are nodulated; nitrogen-fixing bacteria in the nodes form a symbiotic relationship with leadplant [27]. Weaver [133] observed small nodules 10 to 12 feet (3-3.6 m) below the root crown of the 7-year-old plant; nodules occurred along the entire length of some of its roots.
Leadplant is drought-tolerant [53,66,132]. During the Dust Bowl years of 1936 to 1939, leadplant increased its cover on 4 prairie sites in Nebraska, while it disappeared from 2 other sites. Seedlings were noted on some Nebraska sites in 1938 but did not survive [137].
Leadplant occurs across most of the Great Plains. It is apparently extirpated from Montana and is rare in Ontario, Michigan, and Arkansas [65].
States and provinces (as of 2011 [123]):
United States: AR, CO, IA, IL, IN, KS, LA, MI, MN, MO, MT, ND, NE, NM, OK, SD, TX, WI, WY
Canada: MB, ON
Frequent prescribed fires apparently benefit leadplant. In Minnesota, remnant tallgrass prairie communities along Highway 56 have been maintained by frequent prescribed burning. Leadplant is an important component of these prairie remnants and is considered an indicator of remnant sites in good condition [61].
Betz [18] claims that tallgrass prairies and oak savannas cannot be restored without frequent, possibly annual, prescribed fires. An Illinois study investigating the relationship between fire frequency and long-term (25 years) successional changes in ungrazed tallgrass prairies found herbaceous species diversity increased and woody species diversity decreased with increasing fire frequency. This relationship held for both mesic and dry-mesic prairies (abstract by [23]). The studies discussed in Plant response to fire show that typically, leadplant survives frequent grassland fires, usually assuming a forb-like growth form.
The benefits of prescribed fire in tallgrass and mixed-grass prairies include controlling woody species, increasing herbage production, and increasing palatability of bluestems and other coarse tallgrasses. On sites dominated by warm-season grasses such as sideoats grama, spring burning helps control cool-season species [144]. Prescribed fire can also reduce litter build-up, raising soil temperatures and encouraging growth of nitrifying soil bacteria (review by [124]).Fire histories for tall- and mixed-grass prairies are usually not available due to the lack of fire-scarred trees. However, it is certain that fires historically occurred in the Great Plains, and they were probably frequent. Fire histories near prairie-woodland ecotones, such as ponderosa pine woodlands to the west and the oak-hickory woodlands to the east of the Great Plains, have been extrapolated to estimate fire frequencies in adjacent prairies. Such fire histories show a regime of low-severity surface fires ranging from 2 to 25 years apart. Based on pioneer accounts of fires in the settlement period, fire-return intervals ranged from 5 to 10 years in tallgrass prairies and from 20 to 30 years in the dissected, rolling plains on the Edwards Plateau of Texas. Although accurate presettlement fire histories are unknown, it is generally accepted that tallgrass prairies developed under a regime of fires at 1- to 10-year intervals (review by [124]).
Fire exclusion may reduce leadplant cover. Cores from Lake West Okoboji in Iowa revealed that leadplant pollen and seeds were abundant from 9,000 years before present to 1865. Leadplant occurrence in core samples dropped steeply after 1865, which corresponds to the period of European settlement and increasingly fewer prairie fires [9].
See the Fire Regime Table for further information on FIRE REGIMES of vegetation communities in which leadplant may occur. Find further fire regime information for the plant communities in which this species may occur by entering the species name in the FEIS home page under "Find FIRE REGIMES".
Plant response to fire: Leadplant is favored by fire [124] and is rated as fire tolerant [132]. On ungrazed, upland areas of the Konza Prairie Research Natural Area, for example, leadplant was codominant on a big bluestem site that had been spring-burned annually for at least 10 years. Leadplant did not occur on an adjacent unburned site [47]. Because of postfire rhizome sprouting, fire tends to increase leadplant's clonal size [80]. Rather than remove leadplant from prairie landscapes, frequent fire apparently restricts leadplant top-growth, so that leadplant assumes a forb-like appearance and growth form [134,136].
As of 2011, information on leadplant's ability to establish from seed after fire was lacking. One seed bank study suggests that leadplant stores seed in the soil [105], so postfire establishment from soil-stored seed may be possible. Leadplant seeds collected from burned and unburned plots on 2 tallgrass prairies showed no trend in germination when stratified for 4 weeks, then grown in the greenhouse. Small sample size (n=30 seeds/ treatment) [104] makes the study results difficult to interpret. Further tests are needed to determine if fire affects leadplant's ability to germinate.
Germination (%) of leadplant seed from 2 tallgrass Nebraskan prairies [104] Site Burned Unburned Hover Prairie 33 20 Stolley Prairie 3 3 Days to emergence (x, across sites) 14 40Fire may increase leadplant flower and seed production. After fall prescribed burning on the Hayden Prairie in northeastern Iowa, Ehrenreich [43] noted a marked difference in summer flowering on her study sites: "Myriads of flowers of many forbs contributed to a continued contrast of the burned and unburned areas. The number of purple flowers of Amorpha canescens...accentuated this difference". Leadplant showed a similar response after an April prescribed fire on the Kalsow Prairie, Iowa. By August (postfire month 4), the mean number of inflorescences was significantly greater on burned plots (1,016/10 m²) compared to unburned plots (506/10 m²). Is biomass was significantly less on burned than unburned plots in June (postfire month 2), but by August, these differences were not significant (P=0.1) [100]. In Buffalo State River Park, Minnesota, a leadplant population produced more flowers the summer after a spring prescribed fire than before burning. The study site was on a tallgrass prairie-quaking aspen (Populus tremuloides) gallery ecotone [93]. On Wisconsin tallgrass prairie remnants, leadplant flower production was greater on sites burned under prescription in May than on unburned plots. On dry sites, flower production was greater on sites burned in early spring than those burned in midspring. Flower production and growth on dry sites were 50% greater on plots burned on 26 March or 17 April compared to plots burned on 20 May (P≤0.1). On mesic sites, however, flower production and growth were similar on early- and midspring burns [52]. In contrast to these results, there was no significant difference in leadplant raceme production on burned and unburned sites in tallgrass prairie of northwestern Wisconsin [80].
Leadplant generally increases in abundance after prescribed fire. Increases are noted after both spring [73,92] and fall [91] burning.
Several studies have been conducted on the effects of spring prescribed fires on leadplant. In general, even annual burning has little effect on warm-season species such as leadplant if burning is conducted before about 1 May [4,127].
On lowlands on the Konza Prairie, leadplant had greater cover on sites burned annually under prescription than on unburned sites. On uplands, however, leadplant cover was similar on annually burned and unburned sites. Treatment areas were lowland tallgrass prairies on silt clays and upland tallgrass prairies on cherty silt-loams. Big bluestem dominated the community, and leadplant was an important associate in both areas. Annual burning was conducted for 14 years [1].
Mean leadplant cover (%, (SD)) on annually burned and unburned areas of the Konza Prairie [1] Area burned unburned Lowland 4.4 (1.9)a 0.3 (0.1)b Upland 1.1 (0.4)b 1.6 (0.5)b Values followed by different letters are significantly different (P<0.05).In a big bluestem-little bluestem loess prairie in Iowa, the short-term cover of leadplant on prescribed burned sites was greater than leadplant cover on an adjacent, unburned site. Sites were burned in spring (early May), summer (early June), or fall (mid-September) of 1983. By postfire year 3, leadplant cover was greatest on fall-burned plots and least on unburned plots [25]:
Mean leadplant cover (%, (SD)) after burning in different seasons on a tallgrass prairie in Iowa [25] Year Spring Summer Fall Unburned 1981 (prefire) 0 2 (1.2) 2 (1.2) trace 1983 (postfire months 4 & 3 for spring & summer plots, respectively) 1 (0.8) 8 (4.5) no data* 4 (2.1) 1984 (postfire year 1) 4 (2.1) 7 (3.6) 23 (5.2) 5 (2.7) 1986 (postfire year 3) 4 (3.2) 8 (2.7) 16 (4.8) 1 (0.8) *Because burning had not yet been conducted, plots slated for fall burning were not sampled in 1983.Repeated prescribed fires favored leadplant on the Konza Prairie Research Natural Area. Treatments included burning at 1-, 2-, or 4-year intervals or mowing at 1- or 2-year intervals with hay left in place or removed. Treatments began in 1972; the table below reports results as of 1983 (posttreatment year 12). Leadplant cover and frequency were greatest on plots burned every 4 years in April and least on plots mowed in July [46].
Leadplant abundance under different burning and mowing treatments on the Konza Prairie [46] Treatment % cover (% frequency) March burn, 1-yr interval 2.9 (35) April burn, 1-yr interval 10 (37) Nov. burn, 1-yr interval 1.9 (38) April burn, 2-yr interval 11 (77) April burn, 4-yr interval 21 (95) July mow, hay left 0.02 (5) July mow, hay removed 0.2 (5) Nov. mow, hay left 7.2 (95) Unburned 0.4 (22)Leadplant sprouted on an east-central Nebraska big bluestem prairie restoration site after sod transplanting was followed by spring or fall prescribed fires. The authors speculated that leadplant was sprouting from remnant rootstocks (rhizomes) below the 12-inch (30 cm) deep cuts made for sod transplanting. Leadplant had 10% frequency before sod removal, sod transplant, and fire treatments. It had 1% to 3% frequency in postfire year 1 [24].
Leadplant response to season of burning was neutral in dry indiangrass-sideoats grama remnant prairie in south-central Wisconsin. Leadplant was a dominant forb. After late fall, early spring, or late spring prescribed burning for 8 of 10 years (1979-1989), leadplant showed no significant change in density. There was a severe spring and summer drought in 1988; most species declined on all plots during the drought. Leadplant's response to drought, however, was similar to its response to fire: Across treatments, it showed no significant change in density [53].
The authors speculated that the dryness of the sites, especially during the drought, hindered postfire reproduction of leadplant. In 1990, a year of "ample" rain, they observed high leadplant seedling densities [53].
Similarly, leadplant canopy cover and frequency remained stable after 14 years of annual spring or summer prescribed fires on the Konza Prairie. Prior to the study, the sites had been burned under a 3-year rotation, spring-burn prescription. Leadplant was dominant with the 3-year fire rotation, and it remained so with annual burning. The plant community was mixed big bluestem-sideoats grama prairie [121].
Mean percent canopy cover (and frequency) of leadplant in the 1st and 14th year of annual prescribed fires on the Konza Prairie [121] Year Spring fires Summer fires Uplands Lowlands Uplands Lowlands 1994 3.4 (63.4) 2.8 (45.2) 3.4 (64.2) 6.5 (82.6) 2007 3.4 (63.4) 4.0 (56.3) 2.9 (67.8) 7.6 (82.6)On big bluestem rangelands in Kansas, leadplant increased on plots burned annually in fall or winter for 8 years [91].
Because it is slow-growing, leadplant recovery may take decades on degraded prairie sites, even after frequent prescribed fires. On the Willa Cather Memorial Prairie in Nebraska, a program of prescribed fire at least every 3 years and light-intensity, rotation grazing approximately every 4 years was implemented. Leadplant comprised 0.02% of total aboveground plant community biomass the first few years of treatments. After 16 years of treatments, its relative proportion of total aboveground biomass had increased to 0.13%. The plant community was mixed-grass big bluestem-western wheatgrass-little bluestem-sideoats grama prairie. The warm-season grasses, such as sideoats grama, declined "almost to extirpation" under this management [85].
Reviews report that tallgrass prairies accumulate fuels quickly in the absence of fire. Tall grasses typically produce litter more quickly than the litter can decompose. This build-up results in decreased plant productivity and diversity, with much of the decrease attributed to low soil temperatures and nitrate levels that are associated with litter build-up. Historically, grazing and frequent fire reduced this litter build-up [5,30,124,145].
Little information was available on leadplant's relative contribution to fuel loads or its flammability as of 2011. Weaver [135] estimated its average dry-forage production at 150+ lbs/acre in tallgrass prairies across the Northern and Central Great Plains. A survey of 3 big bluestem prairies in Saline County, Kansas, showed leadplant reached greatest aboveground biomass (4.2 g/m²) and frequency (8.3%) in June [95].
Fire top-kills leadplant [17,80,133]. Because grassland fires tend to move rapidly and have relatively low temperatures ([3], review by [5]), the heat rarely penetrates more than 0.4 inch (1 cm) below the soil surface. Soil usually protects root crowns and other belowground tissues of prairie plants from fire (review by [5]).
A laboratory study suggests that grassland fires have little effect on leadplant seed. Leadplant germination with fire surrogate treatments (hot water or scarification) was similar to that of untreated seed. Pouring 140 °F (90 °C) water over leadplant seed and allowing the seed to soak for 4 hours resulted in 48% germination. Tumble scarification for 2 to 3 hours resulted in 58% germination, while untreated seed had 57% germination [40].
Leadplant provides important forage for wildlife and livestock. Stubbendieck and others [118] describe it as "excellent, highly nutritive, and palatable for livestock and wildlife; commonly selected over other species".
Many insects feed on leadplant. A survey on prairie remnants in eastern Minnesota found 47 insect species visited leadplant flowers [98]. Butterflies and honeybees consume leadplant nectar; honeybees also eat the pollen [65,80]. The federally endangered Karner blue butterfly [125] feeds on the nectar [83,108]. Grasshopper, leafhopper, and beetle species browse the foliage [70,80].
Palatability and nutritional value: Typically, leadplant is highly palatable to browsing ungulates [55,117,119,135], which usually select it before other species [117]. In the Central Black Hills, cattle browsed leadplant in summer [126]. However, leadplant use may vary spatially and temporally. In another Black Hills study, white-tailed deer did not browse leadplant [56]. In a restoration project in the Hyland Lake Park Reserve, Minnesota, leadplant was among the species that white-tailed deer, eastern cottontails, and rodents avoided. The area had been plowed and sown with native herbs. Asters (Asteraceae) were most heavily consumed [44].
See these sources: [87,107] for information on the nutritional value of leadplant.
Cover value: Small mammals, nongame birds [39], and game birds use leadplant as cover. On the Sheyenne National Grasslands of North Dakota, prairie sharp-tailed grouse in upland switchgrass (Panicum virgatum) communities used leadplant as their primary day-roost plant [82].
Leadplant is grown as an ornamental [117,128].
Native Americans used leadplant medicinally [65,118,118]. Dried leaves were used to make tea [118,118] and for smoking [118].
Many insects visit leadplant flowers (see IMPORTANCE TO LIVESTOCK AND WILDLIFE), but bees (Apoidea) and beetles (Coleoptera) are apparently the most efficient pollinators. Solitary bees are leadplant's primary native pollinators [113]; honeybees also pollinate the flowers [65]. In northwestern Iowa and southwestern Minnesota, leadplant fruit set increased with increasing bee species diversity (P≤0.03) [113]. In Wisconsin, 3 beetle species pollinated most leadplant flowers [80].
Leadplant is an obligate outcrosser with protogynous flowers [113].
Leadplant apparently has a soil seed bank [105], although longevity of soil-stored seed was unknown as of 2011. In a common garden in Wisconsin, leadplant seeds germinated the year they were sown, with no emergents the next year [60]. In the greenhouse, leadplant seedling emergence was greatest in soils collected from mixed-grass communities in the Loess Hills Wildlife Area of Iowa [105]:
Density of leadplant emergents from soils of different Iowa plant communities [105] Community (dominant species) Emergents/m² Deciduous shrub (Cornus drummondii/Ulmus spp.) 0.0 Deciduous woodland (Ulmus spp./Cornus drummondii) 0.0 tallgrass prairie (Andropogon gerardii-Sorghastrum nutans) 29.3 nonnative grassland (Poa pratensis-Bromus inermis) 64.2 mixed-grass prairie (Schizachyrium scoparium-Bouteloua curtipendula) 128.3Leadplant may comprise a small portion of total plant community seed rain. In a large-scale harvest of seeds in big bluestem-indiangrass tallgrass prairies in Minnesota and North Dakota, leadplant seeds never exceeded 1% of total plant community seed production. To increase total seed yields, most prairies had been burned under prescription the spring before late summer and fall seed collections. Big bluestem and indiangrass dominated the plant communities' seed rains. Seeds were collected for restoration projects [90].
Flower and Leadplant can be a prodigious flower and seed producer. A single plant may support up to 30 flowering stems and 3,000 flowers [113]. In Dickinson County, Iowa, leadplant showed good flower and seed production on remnant prairies, including those on private reserves and along roadsides. Across 8 populations, the absolute number of flowering leadplant stems (and flowering stem density) ranged from 12,545 stems (1 stem/m²) for a population on a private reserve to 14 stems (0.6 stem/m²) for a roadside population. The roadside population had significantly fewer flowers fertilized, more seeds destroyed by predators, and fewer filled seeds than populations from larger areas (P<0.01 for all variables). The reason for this low production was unclear. The authors suggested that small population size was a factor; however, because other small roadside populations showed relatively good flower production, there might have been other contributing factors [54]. In another study in Dickinson County, seed set was not correlated with leadplant population size [80].
On the northern Flint Hills of Kansas, leadplant produced fewer flowering stems on sites with moderate- or high-level cattle grazing intensity than on sites with low-level or no grazing (P≤0.05). Intensities were set as:
low= 0.26 AU/ha
moderate=0.36 AU/ha
high=0.56 AU/ha [55].
No information was available on leadplant seedling establishment.
Leadplant may spread slowly in tallgrass communities [8]. Several researchers reported relatively slow leadplant growth in tallgrass restoration projects [50,110,142]. Leadplant may spread over time, however. After leadplant seedlings were transplanted on the Russell R. Kirt Prairie, Illinois, leadplant frequency increased from 4% in its transplant year to 73% in its 15th year [69]. On an old-field restoration site in Illinois that covered approximately 0.7 acre (0.3 ha), seeded leadplant increased from 4 to 69 plants in 9 years [68].
Site characteristics:
Topography and elevation: Leadplant is a species of dry, sandy flats and valleys [28,111,114], high plains [138], hillsides [28,28,111,111,114,114,118], and streambanks [128]. Weaver [136] reported high leadplant importance values on both upland and lowland sites in tallgrass prairies across the Northern and Central Great Plains; leadplant was the most important forb on uplands and 3rd most important on lowlands [136]. Leadplant is most common on dry plains, slopes [48,114,128], and sand dunes, although it also occurs on wet to mesic sites. In eastern Kansas, it occurs on sand dunes in sand bluestem (Andropogon hallii) communities and in dry valleys in prairie sandreed-blue grama-spike dropseed (Calamovilfa longifolia-Bouteloua gracilis-Sporobolus cryptandrus) communities [63]. A 1917 Kansas publication reported it as common along streams and ditches [115].
There were few reports of leadplant's elevational ranges as of 2011. Leadplant occurs from 3,500 to 4,500 feet (1,100-1,400 m) in Colorado [51] and from 5,300 to 7,000 feet (1,600-2,100 m) in New Mexico [28].
Soils: Leadplant prefers well-drained or dry soils [11,147]. By the Middle Loup River, Nebraska, it did not occur where the water table was shallower than 40 inches (100 cm) above ground level [86]. In central and southern Wisconsin, leadplant grows in deep sands lacking groundwater seepage and in shallow soils above sandstone [71].
Leadplant grows in several different soil textures [118]. It typically grows in sandy, gravely, or rocky soils [21,114,128], although it is found in loams or clay loams in Kansas [78]. Leadplant tolerates slightly acidic [132] to mildly alkaline [66,132] soils. In South Dakota, it grows in mixed-grass sand bluestem-prairie sandreed communities on stabilized sandhills or loamy sands; soil pH ranges from 6.4 to 8.4 [12]. Leadplant grows in alluvium in Kansas [78]. It is considered an indicator species of mesic, mixed-grass shale-limestone prairies of western Kansas. Big bluestem and purple threeawn (Aristida purpurea) dominate these prairies. Soils are clay loams with a modal pH of 7.8 [57]. A leadplant-prairie dropseed (Sporobolus heterolepis) community occurs on gravel and dry-dolomite prairies in Wisconsin [6].
Plant communities: Leadplant occurs in tall- and mixed-grass prairies, moist to mesic meadows and shrublands, oak (Quercus spp.) and conifer savannas and woodlands, and southwestern scrublands. Details on these plant communities are provided below. See the Fire Regime Table for a list of plant communities in which leadplant may occur and information on the FIRE REGIMES associated with those communities.
Prairies: In its core distribution in the Northern and Central Great Plains, leadplant is very common in tallgrass and mixed-grass prairies. Weaver [135] described leadplant as "perhaps the most conspicuous, most widely distributed, and most abundant of prairie plants except for certain grasses" [135]. Leadplant is especially common in sandhill prairies [118,131,140]. Curtis [35] classified leadplant as a characteristic species of Wisconsin's tallgrass prairies, being especially prevalent on dry sites and sites with limestone-derived soils [79].
Leadplant is associated with bluestems (Andropogoneae) throughout its range [11,62,78]. It is the most common subshrub or forb of the tallgrass prairie and is characteristic of the ecosystem [79]. Leadplant is an indicator species of tallgrass prairie in Manitoba, where the tallgrass prairie is on the northern edge of its distribution [64]. It is a characteristic, and often dominant, subshrub in dry-sand and dry-gravel tallgrass prairies of Iowa; it also occurs in rare, mesic tallgrass prairies on moraines and till plains [18]. It is a dominant species in big bluestem-little bluestem (Andropogon gerardii-Schizachyrium scoparium)-leadplant dry to mesic prairies of Iowa [34]. A study of 216 tallgrass prairie sites in Illinois showed leadplant was most abundant in little bluestem-Canada bluegrass (Poa compressa) transition communities situated between mesic lowland and dry, hillslope prairies [31]. Leadplant is important to dominant in Nebraska's sand bluestem-prairie sandreed tallgrass communities [109,139]. A leadplant-sand cherry (Prunus pumila) minor association occurs in sandhill prairies of the Great Plains [36].
Once extensive across the eastern Great Plains [75], tallgrass prairies are now mostly reduced to remnant patches. About 2% of the original tallgrass prairie still existed as of 1996 [102]. Tallgrass prairie once covered about one-third of Minnesota; now, it is one of the state's rarest plant communities. Leadplant and other tallgrass prairie species are most common in remnant patches along roadsides and railway rights-of-way [61].
Leadplant is associated with tallgrass prairies in the Ozark Mountains of Missouri [33,103]. These prairie communities develop on loess hills; indiangrass (Sorghastrum nutans) and little bluestem usually dominate [122].
It may be an important component of mixed-grass prairies [99], although leadplant is not typically dominant. It is most common on well-drained, upland mixed-grass prairies, often called "high prairies" [140]. Dominant short grasses include prairie sandreed, needlegrasses (Stipeae)—especially needle-and-thread grass (Nassella comata)—blue grama, other gramas (Bouteloua spp.), and buffalo grass (Buchloe dactyloides). Big bluestem and little bluestem are dominant tall grasses [12,13,112].
Meadows and shrublands: Leadplant sometimes associates in or near seasonally wet or mesic communities of the Great Plains. It is a minor component of tussock sedge (Carex stricta) meadows in Wisconsin [35]. In Nebraska, it frequents streamsides and lakeshores within the tall dropseed (Sporobolus asper)-little bluestem series. Soils are saturated in spring but drain in summer [63]. Throughout the Northern and Central Great Plains, leadplant may associate in chokecherry (P. virginiana) shrublands near streams, draws, and canyon bottoms [94].
Oak communities: On the eastern edge of the Great Plains, leadplant intermingles in oak (Quercus spp.) savannas and open woodlands [21,114,118,128]. It is especially common in oak-hickory (Carya spp.) savannas on tallgrass prairie-woodland interfaces [21]. The white oak-pin oak (Q. ellipsoidalis)/leadplant community is diagnostic of tallgrass prairie-oak-hickory forest transitions in Wisconsin (review by [147]). Bur oak (Q. macrocarpa), black oak (Q. velutina), white oak, shagbark hickory (C. ovata), and bitternut hickory (C. cordiformis) are typical overstory dominants in oak communities containing leadplant [21,41,147]. Leadplant is a characteristic, and often dominant, subshrub in black oak savannas of Iowa [18]. It is generally common in northern pin oak savannas of the Great Lakes states [106]. In Wisconsin, it has been noted in northern pin oak barrens [59]. Kotar and others [72] describe a white oak-northern pin oak/leadplant habitat type of northern Wisconsin; the type is most common on outwashes. Leadplant is rare in white oak-bur oak savannas and woodlands of southeastern Michigan [2,78].
In the Ozark Mountains, leadplant occurs in upland oak woodlands [33,103]. Overstory dominants include white oak, post oak (Q. stellata), and black oak [74,122].
Conifer communities: At the western, northern, and southern edges of its distribution, leadplant occurs in several open conifer communities. It is sometimes dominant in interior ponderosa pine (Pinus ponderosa var. scopulorum) savannas in the Black Hills [45,58,114], where it occupies the low-shrub layer [120]. It is one of the most common shrubs on cattle rangelands near Rapid City in the central Black Hills [126].
Leadplant occurs in several conifer communities in the Great Lakes states. It may skirt the southern and western edges of northern spruce-fir (Picea-Abies) forest-oak savanna interfaces [71]. In southern Wisconsin, leadplant was noted in a former jack pine (Pinus banksiana)-northern pin oak community that converted to tallgrass prairie after burning twice in 30 years. Also in Wisconsin, it is a dominant component of eastern redcedar (Juniperus virginiana) glades [35]. In Minnesota, leadplant is a component of eastern white pine/low sweet blueberry (Pinus strobus/Vaccinium angustifolium) habitat types [71].
In the Ozark Mountains of Missouri, leadplant occurs in eastern redcedar glades [33,103], and it is a secondary species in shortleaf pine (P. echinata)-oak woodlands [81]. In the Carolinas, leadplant grows in longleaf pine/pineland threeawn (P. palustris/Aristida stricta) savannas [29].
Southwestern scrublands: In eastern New Mexico, leadplant is an occasional to important member of plains mesa sand-scrublands. Honey mesquite (Prosopis glandulosa), shin oak (Q. havardii), or soaptree yucca (Yucca glauca) may dominate the overstory, and a mix of tall- and mixed grasses including big bluestem, purple threeawn, and hairy grama (Bouteloua hirsuta) typically dominate the understory [37].Leadplant prefers open sites [128] but tolerates partial shade [132]. In bur oak communities of Wisconsin, leadplant frequency increased with increasing light intensity [35]. Leadplant may occur in all stages of plant succession on open sites, but it does not occur in closed-canopy forests (see Plant communities).
Leadplant tolerates frequent fire or mowing. When comparing species composition of remnant little bluestem-big bluestem prairies in Illinois, leadplant was found on managed cemeteries dating back to European settlement; most cemeteries with leadplant were burned under prescription "regularly". However, leadplant was not found on unmanaged railroad areas [32]. An Indiana study found leadplant on 23 of 24 pioneer cemeteries surveyed, sometimes surviving on a regularly mowed Kentucky bluegrass (Poa pratensis) lawn. The cemeteries were on silt loams, with big bluestem and indiangrass persisting around tombstones and fencerows [20].
Leadplant decreases with fire exclusion and/or heavy grazing. It is more common on ungrazed than grazed sites [114]. Its absence is considered an indicator of depauperate tallgrass prairies [21]; that is, of tallgrass prairies that have lost an important component of the vegetation (such as palatable forbs) due to continuous heavy grazing, frequent mowing, fire exclusion, or other events that are historically unprecedented.
On the Anderson Prairie State Preserve in Iowa, leadplant had significantly greater cover in undisturbed big bluestem-indiangrass prairie than on plains pocket gopher mounds (P=0.004) [143].Leadplant is used for prairie restoration [89], and its seed is commercially available [117]. It is valuable on many sites due to its nitrogen-fixing ability [27]. However, it may be difficult to establish from seed [19,67,141] or seedling transplants [88,96]. In southern Wisconsin, leadplant showed good survival when transplanted at 1 year old, but it showed poor survival when broadcast seeded or transplanted as seedlings [88]. On tallgrass restoration sites in south-central Kansas, transplanted leadplant seedlings were the 5th-slowest growing of 18 broadleaved species [96]. Transplanted leadplant seedlings showed good survival on a tallgrass restoration sites in Illinois, however. Weather was "ideal" for transplanting [130].
See these sources for propagation information: [16,42,129,132,147].
Leadplant may sprout from rhizomes [24,80,117] or the root crown ([133], review by [147]) after top-kill.
The ability to sprout after dying back to the base enables tallgrass prairie plants to survive fire, drought, frost, browsing, and other top-killing events [5]. Leadplant tends to die back to the base each year, sprouting from basal stems and the root crown (review by [147]). In the greenhouse, poorly watered leadplant seedlings died back to their root crowns, but sprouted within "a few weeks" of regular watering [88].
Amorpha canescens, known as leadplant, downy indigo bush, prairie shoestring, or buffalo bellows, is a small, perennial semi-shrub in the pea family (Fabaceae), native to North America.[2][3] It has very small purple flowers with yellow stamens[4] which are grouped in racemes.[5] Depending on location, the flowers bloom from late June through mid-September.[6][4] The compound leaves of this plant appear leaden[5] (the reason for the common name "leadplant"[4]) due to their dense hairiness. The roots can grow up to 5 m (16 ft) deep and can spread up to 1 metre (3 ft 3 in) radially.[3] This plant can be found growing in well-drained soils of prairies, bluffs, and open woodlands.[5]
Typically between 0.3–1 m (1 ft 0 in – 3 ft 3 in) tall, leadplant can be identified by its small purple flowers grouped in long spikes and its grey-green leaflets that are alternate and pinnately compound.[7] The plant produces fruits in the form of hairy legumes each with one seed inside. The flower and leafing pattern is similar to Amorpha fruticosa, however, A. canescens typically only grows to be 1 meter (3 ft 3 in) high and prefers drier habitats whereas A. fruticosa can grow to be 5 or 6 meters (16 or 20 ft) high and lives in wetter areas.
Leadplant is used for a variety of different purposes. Indigenous peoples such as the Oglala use the plant for medicinal purposes.[8][2] Some indigenous tribes believed that the plant could aide in treating pinworms, eczema, rheumatism, neuralgia, open wounds, and cuts. The leaves of the plant were also used to make a tea and as a smoking mixture when dried, crushed and combined with buffalo fat.[8][9] It is also provides many benefits to the ecosystems it is a part of, for example it provides valuable nutrition for grazing animals and helps prevent soil erosion.[10][3] Leadplant may also be used in landscaping and gardening purposes due to its nitrogen fixing qualities and ability to help prevent erosion.[11] Its nodulated roots are home to nitrogen fixing bacteria which help the plants grow.[11]
Amorpha canescens was described by Frederick Pursh in 1814. It falls under subfamily Papilionoideae of the family Fabaceae.[6] The specific epithet "canescens" is a botanical Latin term meaning "becoming grey".[12] There have been further delineation beyond species of Amorpha canescens into distinct variants (such as the A. canescens var. glabrata) based on the amount of hairs and color of the leaves, however this further distinction is not typically accepted due to the wide variation in pubescence of the plant.[6]
Amorpha canescens can be found in many locations throughout North America, ranging from southern parts of Canada south to Texas and New Mexico and spanning west to Montana and east to Michigan.[2] Leadplant is typically found in dry prairie and savanna communities[13][3] Leadplant prefers drier, well-drained soil of many different textures including sandy, gravely, and rocky soils.[11] Finding leadplant indicates minimal livestock grazing and well-kept land that is not overgrown or that has experienced regular fire.[2][14]
Amorpha canescens, known as leadplant, downy indigo bush, prairie shoestring, or buffalo bellows, is a small, perennial semi-shrub in the pea family (Fabaceae), native to North America. It has very small purple flowers with yellow stamens which are grouped in racemes. Depending on location, the flowers bloom from late June through mid-September. The compound leaves of this plant appear leaden (the reason for the common name "leadplant") due to their dense hairiness. The roots can grow up to 5 m (16 ft) deep and can spread up to 1 metre (3 ft 3 in) radially. This plant can be found growing in well-drained soils of prairies, bluffs, and open woodlands.
