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Given the low-growing stature of poverty oatgrass, cover value for large mammals is negligible. However, Dittberner and Olson [13] found that poverty oatgrass provides fair cover value for small mammals, small nongame birds, and upland game birds in Wyoming.
Poverty oatgrass is a cool-season, native, perennial bunchgrass. Roots are fibrous without rhizomes or stolons, and most of the foliage occurs as a crowed basal clump of leaves. Curved or twisted leaves are 4 to 6 inches (10-15 cm) long and persist with age. The inflorescence is a constricted panicle containing 2 to 13 spikelets. Both male and female flower parts appear on each individual. Florets that cross-fertilize (chasmogamous) are located on the aerial panicle and contain more pollen grains than the unopened, self-fertilized florets (cleistogamous) that are located inside 1 or more of the leaf sheaths throughout their development. Floret lemmas have twisted awns with long, stiff hairs, both of which aid in dispersal [11,22].
Research in a pine-hardwood forest in Michigan found that poverty oatgrass has a population half-life of 2.2 years [42].
Poverty oatgrass inhabits much of the United States. It is distributed from British Columbia east to Newfoundland and south to Florida, New Mexico, and Mexico [11,20,21,25,57]. The Natural Resources Conservation Service provides a map of poverty oatgrass' distribution in the United States (https://plants.usda.gov /plants/cgi_bin/topics.cgi).
Poverty oatgrass has adapted to fire by tillering and establishing from seed after top-kill [32,34,42].
FIRE REGIMES:
FIRE REGIMES for plant communities and ecosystems in which poverty oatgrass occurs are summarized below. 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".
Community or Ecosystem Dominant Species Fire Return Interval Range in Years maple-beech-birch Acer-Fagus-Betula > 1000 sugar maple A. saccharum > 1000 sugar maple-basswood A. s.-Tilia americana > 1000 [5] bluestem prairie Andropogon gerardii var. gerardii-Schizachyrium scoparium 5,29] Nebraska sandhills prairie A. g. var. paucipilus-Schizachyrium scoparium plains grasslands Bouteloua spp. blue grama-buffalo grass B. gracilis-Buchloe dactyloides sugarberry-America elm-green ash Celtis laevigata-Ulmus americana-Fraxinus pennsylvanica beech-sugar maple Fagus spp.-Acer saccharum > 1000 juniper-oak savanna Juniperus ashei-Quercus virginiana yellow-poplar Liriodendron tulipifera wheatgrass plains grasslands Pascopyrum smithii Great Lakes spruce-fir Picea-Abies spp. 35 to > 200 northeastern spruce-fir Picea-Abies spp. 35-200 southeastern spruce-fir Picea-Abies spp. 35 to > 200 [5] Rocky Mountain lodgepole pine* Pinus contorta var. latifolia 25-300+ [1,39] shortleaf pine P. echinata 2-15 shortleaf pine-oak P. e.-Quercus spp. longleaf pine-scrub oak P. palustris-Quercus spp. 6-10 [5] red pine (Great Lakes region) P. resinosa 10-200 (10)** [5,17] red-white-jack pine* P. r.-P. strobus-P. banksiana 10-300 [5] pitch pine P. rigida 6-25 [6,24] eastern white pine P. strobus 35-200 eastern white pine-eastern hemlock P. s.-Tsuga canadensis 35-200 eastern white pine-northern red oak-red maple P. s.-Quercus rubra-Acer rubrum 35-200 loblolly-shortleaf pine P. taeda-P.echinata 10 to Virginia pine-oak P.virginiana-Quercus spp. 10 to aspen-birch Populus tremuloides-Betula papyrifera 35-200 [5] mountain grasslands Pseudoroegneria spicata 3-40 (10)** [1] oak-hickory Quercus-Carya spp. northeastern oak-pine Quercus-Pinus spp. 10 to southeastern oak-pine Quercus-Pinus spp. white oak-black oak-northern red oak Q. alba-Q. velutina-Q. rubra chestnut oak Q. prinus 3-8 northern red oak Q. rubra 10 to post oak-blackjack oak Q. stellata-Q. marilandica black oak Q. velutina little bluestem-grama prairie Schizachyrium scoparium-Bouteloua spp. eastern hemlock-yellow birch Tsuga canadensis-Betula alleghaniensis > 200 elm-ash-cottonwood Ulmus-Fraxinus-Populus spp. 5] *Fire-return interval varies widely; trends in variation are noted in the Species review.Poverty oatgrass is usually associated with frequent burning. Its population maintenance in open woodland and woodland-grassland margins is certainly dependent upon fire [34,49,55]. Conversely, successional advancement in the absence of fire may result in very small populations of poverty oatgrass.
No published sources provide fuel management, fire behavior, or fire use planning information concerning poverty oatgrass.
Poverty oatgrass most commonly inhabits low fertility, sandy or rocky, well-drained soils of old fields, pastures, roadsides, and woodland margins characterized by low soil moisture [11,14,15,22,28]. Poverty oatgrass also inhabits clearcuts, burns, and trampled ground of flat and mountainous areas throughout much of the eastern United States [10]. Poverty oatgrass tends to inhabit shallow A horizons overlying substrates such as limestone, marble rock, sandstone, granite, siltstone, clay, and chert [7,23,26,36].
1 Jack pine
5 Balsam fir
15 Red pine
16 Aspen
17 Pin cherry
20 White pine-northern red oak-red maple
21 Eastern white pine
22 White pine-hemlock
39 Black ash-American elm-red maple
40 Post oak-blackjack oak
42 Bur oak
45 Pitch pine
52 White oak-black oak-northern red oak
55 Northern red oak
70 Longleaf pine
71 Longleaf pine-scrub oak
76 Shortleaf pine-oak
82 Loblolly pine-hardwood
201 White spruce
203 Balsam poplar
218 Lodgepole pine
FRES10 White-red-jack pine
FRES11 Spruce-fir
FRES12 Longleaf-slash pine
FRES13 Loblolly-shortleaf pine
FRES14 Oak-pine
FRES15 Oak-hickory
FRES17 Elm-ash-cottonwood
FRES18 Maple-beech-birch
FRES19 Aspen-birch
FRES21 Ponderosa pine
FRES23 Fir-spruce
FRES26 Lodgepole pine
FRES36 Mountain grasslands
FRES38 Plains grasslands
FRES39 Prairie
K010 Ponderosa shrub forest
K011 Western ponderosa forest
K016 Eastern ponderosa forest
K017 Black Hills pine forest
K047 Fescue-oatgrass
K050 Fescue-wheatgrass
K051 Wheatgrass-bluegrass
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
K093 Great Lakes spruce-fir forest
K095 Great Lakes pine forest
K096 Northeastern spruce-fir forest
K098 Northern floodplain forest
K099 Maple-basswood forest
K100 Oak-hickory
K101 Elm-ash forest
K102 Beech-maple forest
K103 Mixed mesophytic forest
K104 Appalachian oak forest
K106 Northern hardwoods
K107 Northern hardwoods-fir forest
K108 Northern hardwoods-spruce forest
K109 Transition between K104 and K106
K110 Northeastern oak-pine forest
K111 Oak-hickory-pine
K112 Southern mixed forest
101 Bluebunch wheatgrass
102 Idaho fescue
103 Green fescue
109 Ponderosa pine shrubland
110 Ponderosa pine-grassland
215 Valley grassland
216 Montane meadows
218 Lodgepole pine
237 Interior ponderosa pine
251 White spruce-aspen
253 Black spruce-white spruce
254 Black spruce-paper birch
301 Bluebunch wheatgrass-blue grama
302 Bluebunch wheatgrass-Sandberg bluegrass
303 Bluebunch wheatgrass-western wheatgrass
310 Needle-and-thread-blue grama
411 Aspen woodland
502 Grama-galleta
601 Bluestem prairie
604 Bluestem-grama prairie
606 Wheatgrass-bluestem-needlegrass
607 Wheatgrass-needlegrass
611 Blue grama-buffalo grass
613 Fescue grassland
704 Blue grama-western wheatgrass
705 Blue grama-galleta
709 Bluestem-grama
710 Bluestem prairie
714 Grama-bluestem
717 Little bluestem-Indiangrass-Texas wintergrass
802 Missouri prairie
809 Mixed hardwood and pine
920 White spruce-paper birch
Fire usually top-kills poverty oatgrass [32,34,42].
While studying the population dynamics of poverty oatgrass during secondary succession of a pine-hardwood forest in northern lower Michigan, Scheiner [42] found that fire's predominant effect was mortality. Seventy-five percent of individuals had died in an experimental plot burned the previous summer.
Importance of poverty oatgrass to wildlife and livestock is limited to early season utilization. However, palatability and preference vary according to local growing conditions and relative abundance of other forage [40].
Poverty oatgrass is a component in many grass, shrub, and forest habitats. Despite its abundance,
poverty oatgrass is not cited as a habitat type indicator species because it is a secondary successor
on burned and anthropogenically disturbed sites. Common eastern and prairie
associates of poverty oatgrass include lowbush blueberry (Vaccinium angustifolium), goldenrod (Solidago spp.),
bracken fern (Pteridium aquilinum), little bluestem (Schizachyrium scoparium),
junegrasses (Koelaria spp.), threeawans (Aristida spp.), panicgrasses (Panicum spp.),
wheatgrasses (Triticeae), fescues (Festuca spp.), needlegrasses (Achnatherum spp.), and
bluegrasses (Poa spp.) [15,33,36,42,46,50,58].
Compared to graminoid associates, nutritional value of poverty oatgrass is low. Ungulate use is generally restricted to early season when protein value is optimal [15].
Most sources cite poverty oatgrass as rather unpalatable to livestock throughout the growing season
[8,13,22,40]. However, Skovlin and others [45] found that poverty oatgrass was second only to bluebunch wheatgrass (Pseudoroegneria spicata) for utilization by cattle over an 8-year period at 3 different stocking levels. This study, conducted in the ponderosa pine (Pinus ponderosa)/bunchgrass range of the Pacific Northwest, showed heaviest use of poverty oatgrass during season-long and
deferred grazing rotations. If utilized by domestic and wild ungulates, poverty
oatgrass' young green blades are preferred in early spring and summer for optimal palatability. Poverty oatgrass is much less palatable by midsummer [15]. The palatability of poverty oatgrass for wildlife in Wyoming
has been rated as follows [13]:
In the southern and eastern United States, poverty oatgrass begins active growth in early spring. Flowers develop and bloom from late spring to early June. Seed maturation and shattering closely follow pollination. Poverty oatgrass is commonly dormant during the hot summer months. A period of vegetative growth may occur when temperatures decrease in early fall. In Canada, seasonal development occurs a few weeks later as a result of temperature and photoperiod restrictions [11,28].
Most barrens, forested, prairie, and flatwood ecosystems show a marked increase in poverty oatgrass populations the growing season following fire [32,34,41,42,49,55,56]. Open-grown poverty oatgrass plants may produce 4.5 times more vegetative culms and 1.5 times more flowering culms than those growing in more successionally advanced communities. During the 1st few growing seasons following fire, poverty oatgrass allocates its resources to vegetative growth over reproductive effort. As the canopy of more advanced successional stages reduces light reaching the herbaceous layer, this trend reverses. In general, environmental changes imposed by successional trends contribute to a drastic population reduction 20 to 30 years following fire [42].
Despite the overwhelming evidence supporting fire's contribution to poverty oatgrass establishment and success, some grassland ecosystems show a decrease in poverty oatgrass following frequent disturbance [33,50]. While observing floristic trends of annually burned, post-agricultural little bluestem fields, Nierling and Dreyer [33] noticed a drastic decrease in poverty oatgrass. Similarly, prescribed burns in goldenrod-poverty oatgrass communities resulted in a 26% decrease of poverty oatgrass frequency, while unburned fields supported contiguous poverty oatgrass plants. In this particular community type, fire temporarily promoted forb dominance followed by a slow emergence of poverty oatgrass [50].
Ground residual colonizer (on-site, initial community)
Tussock graminoid
Poverty oatgrass reproduces by seed and by tillering [11]. Its production of cleistogamous flowers and chasmogamous flowers makes this species highly self-compatible and often dominant in favorable growing conditions. Chasmogamous florets are more abundant than self-fertile florets. Cleistogamous florets occur most frequently in plants growing on disturbed, grazed, wooded, and mountainous areas [9]. The presence of both flower types in varying proportions yields 2 different reproductive strategies. However, seed production through self-pollination in closed florets is most common [35].
While conducting a study on poverty oatgrass reproduction, Clay [9] observed that healthy plants set seed in all 200 of observed florets of both flower types. Pronounced twisted and pubescent awns aid in seed dispersal. Maximum germination of seeds was investigated by Toole [51]. Seeds taken from the Shenandoah National Forest in Virginia germinated best when temperatures were alternated between room temperature and 95 degrees Fahrenheit (35 oC). A 71% sulfuric acid treatment weakened the seed coat, facilitating germination. Prechilling the seeds at 37 degrees Fahrenheit (3 oC) before room temperature germination with a potassium nitrate treatment was also effective.
Seeds of poverty oatgrass are highly dormant but germinate readily on exposed mineral soil. Even if the aboveground population no longer exists, seeds may remain in soil for decades before a disturbance such as fire initiates another population [43].
2 Cascade Mountains
5 Columbia Plateau
8 Northern Rocky Mountains
9 Middle Rocky Mountains
10 Wyoming Basin
11 Southern Rocky Mountains
12 Colorado Plateau
13 Rocky Mountain Piedmont
14 Great Plains
15 Black Hills Uplift
Poverty oatgrass is a secondary successor of burned and/or cut sites, old fields, and old pastureland [14,15,19,38,47]. It is a common pioneer on northeastern coastal sandplains and old domestic sheep pastures [14]. Its ability to colonize after disturbance is attributed to long periods of seed dormancy [31]. Optimally growing in high light, conditions are most favorable for poverty oatgrass during early years of succession [42]. As competition for light and other resources increases, poverty oatgrass populations decrease [3]. Individuals appearing in mid-late successional stages of natural reforestation allocate most resources to reproductive efforts in order to continue the population [43].
Some barren and alvar ecosystems are kept in early succession by repeated fires [7,46]. Smith and Sparling [46] found poverty oatgrass was a persistent member of jack pine (Pinus banksiana) barrens maintained by frequent fire. A prairie and savanna restoration study conducted in central Wisconsin showed marked increases in poverty oatgrass populations with increased prescribed burning [4]. However, it should be noted that some grasslands dominated by poverty oatgrass might be drought-dependent, not fire-dependent [7].
The currently accepted scientific name of poverty oatgrass is Danthonia spicata (L.) Beauv. ex.
Roem. & Schult. (Poaceae) [20,21,25,27,57].
Poverty oatgrass inhabits sites of varying nutrient and moisture content. However, special interest is given to its ability to establish and succeed on sites of particularly poor nutrient and moisture regimes, such as roadsides [22]. It protects soil from erosion and excessive nutrient leaching, and is frost-heave resistant. Poverty oatgrass also has the ability to inhabit acidic soils (pH 4.5-4.7) [54]. Most sources cite poverty oatgrass as a common secondary successor and valuable erosion controller of fire-disturbed areas and clearcuts in the eastern United States [10].
Не має кореневищ або столонів. Стебла довжиною 20–80 см. Бокові гілки відсутні. Листя в основному базальне. Листові пластини вигнуті, довжиною 7–15 см; шириною 1–2 мм. Суцвіття — волоть. Волоть лінійна довжиною 2–5 см з кількома колосками. Колоски одиночні. Родючі колоски з квітоніжками. Квітоніжки довжиною 1-3 мм. Колоски довжиною 10–13 мм, з 4–9 родючими квіточками, розпадаються при зрілості. Колоскові луски стійкі, подібні, перевищують верхівки квітів, тонші, ніж родюча лема. Колоскові луски ланцетні, довжиною 10–13 мм, без кіля, 3–5-жильні, верхівка загострена. Родюча лема еліптична, 3.5–5 мм довжиною, папероподібна, без кіля; 5-жильна. Пиляків 3.
Північна Америка: південна Ґренландія, більша частина Канади, США, північ Мексики. Зростає в багатьох видах середовища існування, в різних екосистемах лісових і пасовищних угідь. Легко росте на бідних, сухих, кам'янистих ґрунтах. Коли середовище проживання порушується, наприклад, після пожежі, насіння, довго заховане в ґрунті, стимулюється і проростає, роблячи рослину піонерним видом.
Danthonia spicata là một loài thực vật có hoa trong họ Hòa thảo. Loài này được (L.) Roem. & Schult. mô tả khoa học đầu tiên năm 1817.[1]
Bài viết chủ đề Họ Hòa thảo này vẫn còn sơ khai. Bạn có thể giúp Wikipedia bằng cách mở rộng nội dung để bài được hoàn chỉnh hơn. Danthonia spicata là một loài thực vật có hoa trong họ Hòa thảo. Loài này được (L.) Roem. & Schult. mô tả khoa học đầu tiên năm 1817.
