Rosinweeds of the Prairies Nature Bulletin No. 198-A September
18, 1965 Forest Preserve District of Cook County Seymour Simon,
President Roland F. Eisenbeis, Supt. of Conservation ROSINWEEDS
OF THE PRAIRIES More than half of Illinois, the Prairie State,
was originally prairie -- largely the Tall Grass Prairie
characteristic of the climatic zone where the annual rainfall
averages 35 inches or more, dominated by such grasses as the big
bluestem and coarse slough grass which grew 6 to 8 or more feet
tall, so thickly that most other plants were excluded. The
ridges and uplands, however, were characterized by the little
bluestem and similar grasses growing from 2 to 4 feet tall.
Plants are crowded in a prairie. There is severe competition for
sunlight, food and moisture. The early spring plants are mostly
small and low, growing rapidly to mature before they are
overshadowed by the grasses. By midsummer, taller plants that
bloomed in late spring are nearly hidden. But the late summer
and autumn blooming plants cont