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Osage Plains
(Area - 24,559,400 ha)
Executive Summary |
Description - The Osage Plains, covering west-central Missouri, the
southeastern third of Kansas, most of central Oklahoma, and extending into north-central
Texas, is the southernmost of three tallgrass prairie physiographic areas. It grades into
savannah and woodland to the east and south, and into shorter mixed-grass prairie to the
west. The Osage Plains consist of three subregions. The Osage Plains proper occupy the
northeast segment. Although sharply demarcated from the Ozark uplift, the Plains are
nonetheless a transitional area across which the boundary between prairie and woodland has
shifted over time. In the central portion of the physiographic area lies the second
subregion, the Flint Hills. This large remnant core of native tallgrass prairie is a rocky
rolling terrain that stretches from north to south across Kansas and extends into
Oklahoma. To the west and south of these hills are the Blackland Prairies and
Crosstimbers. This vegetatively complex region of intermixed prairie and scrubby
cedar-mesquite woodland extends into north-central Texas. As in the rest of the Great
Plains, fire, herbivory, topography, and drought maintained prairie and established the
location of woodlands. |
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Conservation recommendations and needs - About 70% of this physiographic area and
almost all of the Flint Hills subregion were tallgrass prairie prior to European
settlement. Conversion of land to agriculture and the increase in woodland following fire
suppression has greatly diminished the percentage of grass in the Osage Plain and
Blackland Prairie and Crosstimber subregions. However, some high quality landscapes
supporting relatively large populations of Prairie-Chickens and/or Henslows Sparrows
remain. In fragmented landscapes, PIF suggests consideration of a series of Bird
Conservation Areas designed to perpetuate the highest priority birds. The Flint Hills have
been dominated by livestock ranching rather than rowcrops, and grassland landscapes remain
largely unfragmented. Because lack of fragmentation often is associated with low levels of
nest predation and brood parasitism, breeding birds may produce an abundance of offspring
able to re-colonize grasslands in the fragmented areas of the Midwest. Although light
livestock grazing can result in habitat structure that is attractive to some high priority
birds, annual spring burns and overgrazing can result in landscapes that are too
homogeneous to meet the needs of all priority species. Nevertheless, PIF supports ranching
and good range management as a means of accomplishing bird conservation objectives.
Indeed, any other likely use of the land could be disastrous for birds. Because priority
shrub birds may be able to prosper in relatively small patches of quality habitat, PIF
suggests that small wildlife areas that cannot be part of a productive grassland system be
managed as shrub habitat for Bells Vireo and other shrub birds. Riparian forest
birds are largely peripheral in this area, but some suitable sites on the eastern fringes
could be managed for this suite. A variety of wetland habitats should be maintained
primarily for high priority in-transit migratory shorebirds. In addition, PIF recommends
maintenance of riparian strips for in-transit migratory landbirds. |
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