Prairies, as the picture suggests, consist mainly of grasses and wildflowers; few trees or shrubs are found there. In 1820, at least 60% of Illinois' land area, mainly in the northern part of the state, was grasslands of one type or another. Prairie land makes very good farm land, however, and by the end of the nineteenth century, farmers had plowed and planted much of Illinois' original prairie. Industrialization and the growth of cities like Chicago took care of much of what remained, and today 99.99% of the original prairie is gone.
The high-quality prairie that has survived--only 2352 acres--is generally fragmented into small packages of a few acres or less, often scattered along highways and railroads. Far-ranging prairie species, such as the bison or black bear, could never survive in so diminished a habitat, and many species of birds, plants, and insects also require larger patches of prairie in order to survive. In all, 18 prairie species have been extirpated since the European settlement of Illinois and 127 more species are considered threatened or endangered.