• The prairies of the central plains have a great diversity of plant life.prairie 2 image by John Maldoror from Fotolia.com
  
  According to the National Park Service, less than four percent of America's tall grass prairies are still in existence, with the rest under agricultural development. Despite the rough exterior of the tall grass prairie ecosystem, it is actually a very delicate biome with a great diversity of plant life. There are over 500 species of plants in the tall grass prairie, although only a fraction of those are trees. Despite their scarcity, trees hold an important place in the ecological well-being of the tall grass prairie, providing habitat for birds and small animals, as well as windbreaks to lessen the impact of erosion.
  
  

Eastern Cottonwood Poplar

• The eastern cottonwood poplar (Populus deltoides) is commonly found throughout the tall grass prairie, along waterways and creek banks. Although the species can grow to nearly 150 feet in height, it is significantly shorter when growing on the prairie, owing to the high winds and scant precipitation. The eastern cottonwood poplar is the most widespread tree in the tall grass prairie ecosystem.
  
  

Oaks

• The dominant tree in the transitional areas between the tall grass prairie and the savannah is the oak. There are seven species of oak in the region, but of those only three are common: post oak (Quercus stellata), dwarf chinkapin oak (Quercus prinoides) and blackjack oak (Quercus marilandica). Sometimes called iron oak, the post oak is the most common species throughout the transitional region. Generally creating moderately-sized stands along sandy ridges and dry washes, the post oak is renowned for its durable wood and hardy constitution. The dwarf chinkapin oak is a very small tree, growing less than 20 feet tall and bearing large tufts of lobed, elliptically-shaped leaves. It starts producing acorns at only three or four years of age and has consistently large yields. Blackjack oak is one of the smallest of the red oak group, only reaching 50-feet in height. It, along with post oaks, forms the savannah region between the tall grass prairie and the hill region.
  
  

Willows

• There are two species of willow that account for the majority of tree life along the creeks of the tall grass prairie: coastal plain willow (Salix caroliniana) and black willow (Salix nigra). Both species have shrubby growth and long, lance-shaped leaves with greenish-yellow flowers in the spring, but they differ in height and soil preference. The coastal plain willow, as the name suggests, strongly prefers growing in or near water and sandy soil, whereas the black willow can grow in dry, heavy soil because of its well-developed taproot. Both recover quickly from the periodic fires that sweep through the tall grass prairie, although fire alters the growth habit of both species, enhancing their shrubbery-like qualities.