The North American Prairie
By: Zac Vickers
What is a Prairie?
A prairie is considered, by most ecologists, to be part of the temperate grassland, savannas, and shrubland biome, based on the similarities in climates, moderate rainfall, and a composition of grasses, herbs, and shrubs, rather than trees as the dominate vegetation type.
The Types of Prairies
The Tallgrass Prairie
- Grasses grow from 6-10 feet in height during the summer.
- Easternmost section of the grassland.
- Located in the driest part of the plain in the western edge against the Rocky Mountains.
- Grasses only grow about a foot tall.
- Found between the Tall and Shortgrass prairies
- Has both tall and short grass growing in them.
The Tallgrass Prairie
The Shortgrass Prairie
The Mixedgrass Prairie
North American Prairie Yearly Temp.
North American Prairie Yearly Rainfall
The Seasons on the Prairie
- Cooler than summer, but warmer than winter.
- Rainfall is the lowest over the entire year.
- Summer temperatures can be well over 100 degrees Fahrenheit
- Droughts are common
- Fires are more likely to occur
- Cooler than in the summer, but warmer than in the winter.
- Rainfall higher than the winter, but lower than the summer.
- Winter temperatures can be as low as -40 degrees Fahrenheit.
- Droughts less common
- Some plants die due to extreme cold
Temperate grasslands have a low diversity of wildlife, but a high abundance of wildlife. In North America the dominant grazing animals are bison and pronghorn. Rodents include pocket gophers and prairie dogs. Carnivores include wolves, coyotes, swift foxes, badgers and black-footed ferrets. Birds include grouses, meadowlarks, quails, sparrows, hawks and owls.
- Some animals, such as bison, have broad, flat-topped teeth and digestive systems especially adapted to feed on grasses.
- Many prairie animals have front legs and paws that allow them to burrow into the ground, where they are protected from predators.
- Many prairie animals are adapted for nocturnal life; that is, they are active at night, which helps conceal their presence from predators.
- The color of many prairie animals blends in with the plant life, which also helps them hide from predators or prey, depending on the animal.
The soil in the prairie is rich in nutrients that have with the growth of grasses, soft so the roots of the grass can move through them more freely and with much less resistance, and thick (there are at least 10 inches of nutrient-rich topsoil)
Grasses are the dominant vegetation. Trees and large shrubs are largely absent. Seasonal drought, occasional fires and grazing by large mammals all prevent woody shrubs and trees from becoming established. A few trees such as cottonwoods, oaks and willows grow in river valleys, and a few hundred species of flowers grow among the grasses. The various species of grasses include purple needlegrass, blue grama, buffalo grass, and galleta. Flowers include asters, blazing stars, coneflowers, goldenrods, sunflowers, clovers, psoraleas, and wild indigos.
- During a fire, while above-ground portions of grasses may perish, the root portions survive to sprout again
- Some prairie trees have thick bark to resist fire
- Prairie shrubs readily resprout after fire
- Roots of prairie grasses extend deep into the ground to absorb as much moisture as they can
- Extensive root systems prevent grazing animals from pulling roots out of the ground
- Prairie grasses have narrow leaves which lose less water than broad leaves
- Grasses grow from near their base, not from tip, thus are not permanently damaged from grazing animals or fire
- Many grasses take advantage of exposed, windy conditions and are wind pollinated
- Soft stems enable prairie grasses to bend in the wind