Winnebago county, located in northern Illinois is a zone of ecological transition. This is Part 1 of 3 describing the meeting of three distinct Physiographic zones as described by Partner’s In Flight.
The Dissected Till Plains occupies part of the northwest of Illinois and spreads through most of Iowa, and parts of Missouri, Nebraska, Minnesota, and Kansas. The range ends in Winnebago county.
“Natural vegetation is a mosaic of tallgrass bluestem prairie and oak-hickory forest with oak savannahs characteristic of transition zones. Bottomland hardwoods grow in river valleys.” (Partners In Flight)
Some of the key species of birds for this area are: Greater Prairie-Chicken, Henslow’s Sparrow, Bobolink, Field Sparrow, and Loggerhead Shrike. Of these birds only the Henslow’s and Field Sparrows have been confirmed nesters in the last few years in Winnebago. Historically, Greater Prairie-Chickens boomed in the western part of the county but are no more.
Other birds associated with grassland areas of the Dissected Till Plains are Dickcissels and Grasshopper Sparrow. Grasslands with shrub-areas would include species like Bell’s Vireo (confirmed nester) and Brown Thrasher (relatively common).
Extensive data can be gleaned from the 60-page plan created by Partner’s In Flight.