Natural Features of Kansas
The Kansas landscape was formed by alternating periods of deposition and erosion. The various herpetofaunal ecoregions are defined by their consilient properties to form general species range boundaries over time. Each herpetofaunal ecoregion is largely demarcated by unique components of geology, soils, hydrology, and climate, and the combined interactions of those elements upon the natural history, life history, physiology, and behavior of the local flora and fauna.
One doesn't have to spend much time traveling across Kansas to realize the pronounced influence that humans have exerted upon the Kansas landscape. The greatest impact being the expansive conversion of diverse grasslands to the monoculture of cropland. Only those very few prairie landscapes that are impractical to convert due to topography or geology have been conserved.
— The Kansas-Nebraska Act of May 1854, created the Territory of Kansas, which extended from the western boundary of Missouri to the summit of the Rocky Mountains and from 37° to 40° latitude on the south and north.
Kansas became a state following the ratification of the Wyandotte Constitution (the fourth attempt at creating such by the inhabitants of the Kansas Territory) by the US Congress and upon the signing by President James Buchanan of that bill into law on January 29, 1861.
The Wyandotte Constitution set the present borders of Kansas thusly:
- East – Previously defined by the Missouri Constitution (10 August 1821) as the western edge of Missouri (the meridian line passing through the middle of the mouth of the Kansas River and the then following the Missouri River northwest).
- South – The 37th parallel of north latitude.
- West — The 25th meridian of longitude west from Washington. A line of longitude at approximately 102.05° W (actually 102.46666666° W) of the Prime Meridian of Greenwich.
- North – The 40th parallel of north latitude.
Kansas’ distinctive shape is a combination of both natural and arbitrary geometric boundaries as initially delimited. Kansas is essentially a projected geo—spherical rectangle, with a portion of the northeast cut off by the Missouri River. Lines of latitude run in parallel circles that never intersect, while lines of longitude converge at the poles. Consequently, the width of Kansas gradually decreases from south to north.
Boundary delimitation (as described above) is the theoretical description of a border. However, what's more, relevant is boundary demarcation, the surveying and marking out the border on the ground.
The first boundary survey (following the Kansas—Nebraska Act) began in 1857. The surveyors were tasked with demarcating Congress's delimitations into actual boundary markers. The official border would not be the delimited one, but the demarcated one. The surveyors did a remarkable job considering the size of the task and the limitations of their tools — principally magnetic compasses and metal chains. The resulting demarcation produced many slight errors and inconsistencies as they attempted to stake straight lines over often inhospitable terrain. Those perturbations persist today, and as demarcated Kansas has an area of 82,278 mi2
Subsequently, Kansas was organized (and often re-organized) into counties. Currently, there are 105 counties in Kansas.
Topology – Elevation in Kansas generally decreases from west to east. The highest point (4,041 ft above sea level) is on Mount Sunflower near the Colorado border in Wallace County (~64 miles south of the northwest corner of Kansas). The lowest point (679 ft) is where the Verdigris River enters Oklahoma in Montgomery County (~54 miles west of the southeast corner of Kansas). The western two—thirds of the state has a generally flat surface (dissected and undulating near principal river drainages), while the eastern third has many hills and forests..
Geology – Kansas is underlain by a sequence of horizontal to gently westward dipping sedimentary rocks. A sequence of Mississippian, Pennsylvanian and Permian rocks outcrop in the eastern and southern part of the state. The state's western half has exposures of Cretaceous through Tertiary sediments, the latter derived from the erosion of the uplifted Rocky Mountains to the west.
The Ozark Plateau in extreme southeastern Kansas is comprised of rocks deposited during the Mississippian Period of geologic history, about 350 million years ago. Landforms in the Ozark Border, Osage Plains, and the Cross Timbers are all Pennsylvanian in age, deposited about 300 million years ago. The Flint Hills of east-central Kansas and the Red Hills in the south-central part of the state are both Permian in age, roughly 250 million years old.
Cretaceous—age rocks were deposited approximately 100 million years ago; while much of Kansas was a vast interior sea, form the landscape in the Smoky Hills and part of the Red Hills. The Western Plains and Cimarron Plains of western Kansas are composed of rock debris washed off the face of the Rocky Mountains over the past few million years. The Arkansas River Sandsage Prairie and Arkansas River Sand Prairie are areas of recent alluvial deposition that border the Arkansas River.
Glaciers moved into Kansas several times for 750,000 to 10,000 years ago and scoured the northeastern corner of the state (bounded by the current Big Blue and Kansas rivers), leaving granitic rocks from far away and dense beds of loess soils.
Hydrology — Nearly 75 miles of the state's northeastern boundary is defined by the Missouri River. The Kansas River, formed by the confluence of the Smoky Hill and Republican rivers at Junction City, joins the Missouri River at Kansas City, after a course of 170 mi across the northeastern part of the state.
The Arkansas River, rising in Colorado Rocky Mountains, flows with a bending course for nearly 500 mi across the western and southern parts of the state. With its tributaries, (Little Arkansas, Ninnescah, Walnut, Cow Creek, Cimarron, Verdigris, Spring, and the Neosho), it forms the southern drainage system of the state.
Kansas's other principal rivers are the Saline and Solomon, tributaries of the Smoky Hill River; the Big Blue, Delaware, and Wakarusa, which flow into the Kansas River; and the Marais des Cygnes, a tributary of the Missouri River. The Spring River in extreme southeast Kansas demarks the northwestern edge of the Ozark Plateau.
Kansas Drainage Basins.
Kansas' Principal Rivers.
Vegetation – The potential vegetation types exhibited in Kansas are largely determined by climate, hydrology, and soil characteristics. In general, as one goes west from the eastern edge of Kansas, the trees become more sparsely distributed (or confined to riparian areas) and the grass communities become shorter in stature.
Along the Missouri River border and within the Ozark Plateau (area bound by the Spring River in southeast Kansas) were predominant stands of oak-hickory forest.
Bordering those areas and following the Marias des Cygnes River (as far west as Allen, Anderson, Franklin, and Shawnee counties) and Kansas/Missouri rivers (as far west as Leavenworth, Atchison, and Brown counties) the forest opened up to a mosaic with mixed tallgrass prairie.
Beyond that, to the center of the state and including the Flint Hills, the area was largely mixed tallgrass prairie with floodplain forests. The notable exception is the oak-hickory Cross Timbers area, which persists in pockets from Chautauqua to Greenwood to Woodson to Labette counties.
The central portion of Kansas is mixed prairie and the western quarter is shortgrass prairie. Signification sections of sand and Sandsage prairie lie adjacent to the Arkansas and Cimarron rivers.
Agricultural and silvicultural actives have significantly altered the potential natural vegetation in Kansas. And urban sprawl from Johnson and Wyandotte counties to Shawnee County and much of eastern Sedgwick County has obfuscated those vegetative communities. Few stands of old-growth forest persist and most arable prairies have been converted to a monoculture of croplands (wheat, sorghum, soybeans, corn, and cotton predominately). Only the areas with significant topographical relief (Red Hills Prairie, Smoky Hills, etc), are too rocky (Flint Hills) or have been set aside (Cimarron National Grassland) have been spared the plow.
Kansas Potential Natural Vegetation.
Climate — Kansas's climate can be characterized in terms of three types according to the Köppen climate classification: it has humid continental, semi-arid steppe, and humid subtropical. The eastern two—thirds of the state has a humid continental climate, with cool to cold winters and hot, often humid summers. Most of the precipitation falls during both the summer and the spring.
The western third of the state has a semiarid steppe climate. Summers are hot, often very hot, and generally less humid. Winters are highly variable between warm and very cold. The western region receives an average of about 16 inches of precipitation per year. Chinook winds in the winter can warm western Kansas into the 80 degrees Fahrenheit range.
The far south-central and southeastern portions of the state, have a humid subtropical climate with hot and humid summers, milder winters, and more precipitation than elsewhere in Kansas. Some features of all three climates can be found in most of the state, with droughts and variable weather between dry and humid not uncommon, and both warm and cold spells in the winter.
Temperatures in central Kansas reach 100 °F or above on most days of June, July, and August. These temps are often accompanied by high humidity and therefore dangerous heat indices. Temperatures are often higher in southwest Kansas, but it is less humid and the heat indices there are usually lower than the actual air temperature.
Although temperatures of 100 °F or higher are not as common in areas of eastern Kansas, higher humidity leads most summer days to heat indices between 107 °F and 114 °F. During the summer, nightly low temperatures in the northeastern part of the state, struggle to fall below 80 °F.
Precipitation ranges from about 47 inches annually in the state's southeast corner to about 16 inches in the southwest. Snowfall ranges from around 5 inches along the southern border, to 35 inches in the far northwest. Frost-free days range from more than 200 days in the south to 130 days in the northwest.
Kansas is prone to severe weather, especially in the spring and early summer. Despite the frequent sunshine throughout much of the state, due to its location at a climatic boundary prone to intrusions of multiple air masses, the state is vulnerable to strong and severe thunderstorms. Some of these storms become supercell thunderstorms; these can produce tornadoes, high straight-line winds, and large hail.
The highest recorded temperature recorded in Kansas is (121 °F) on July 24, 1936, near Alton in Osborne County, and the all-time low is −40 °F on February 13, 1905, near Lebanon in Smith County. Interestingly, Alton and Lebanon are approximately 50 miles (80 km) apart.
Herpetofaunal Ecoregions – At any given locality, the abiotic factors listed above interact with characteristics of the biotic elements occurring there. Collectively those localities where a particular species is present determine its geographic range. The Herpetological Ecoregions shown below were delimited by examining repeated range boundary patterns for the reptiles and amphibians in Kansas. And then characterizing those areas by their abiotic and biotic (primarily vegetation) characteristics. The ecoregions depicted below are used throughout the KHA distribution and habitat descriptions.
Herpetofaunal Ecoregions of Kansas.