Area at a Glance

Originating near Woodstock in McHenry County, the Kishwaukee basin has an area of 1,250 square miles.

Its river valley is open oak woodland and prairie country on low undulating land; steeper topography occurs in the northern parts of Boone and Winnebago counties.

The majority of the land is devoted to agriculture with croplands accounting for two-thirds of the surface area.

The northern branch of the Kishwaukee originates in Woodstock in McHenry County and flows in an east-west direction to Cherry Valley. The average width is 50 feet, but as the stream flows past the Boone County line it becomes wider and deeper.

The southern branch has its origin high upon the Cropsey Moraine, just north of Shabbona. It flows in a northeasterly direction until the village of Genoa where it turns left, flowing west-northwest. The southern branch cuts across moraines and part of its stream bed is the plain of an ancient lake. The average width is 55 feet.

The Illinois Water Quality Report rated 86.5% of the Kishwaukee sub-basin as "full support" and the Biological Stream Characterization rated the Kishwaukee River upstream from the South Branch as an "A" stream, a Unique Aquatic Resource.

Three areas of the Kishwaukee River watershed are recognized as Biologically Significant Streams because they support a high mussel and fish diversity.

Glaciation has left moraines, sub-glacial channels, terraces, out­wash fans, valley train deposits, and bedrock highs in the area.

End moraines mark the western boundary of the Wisconsinan glaciation. The Marengo Moraine is the oldest in the area and is one of the most striking glacial landforms in Illinois.

Several natural areas and a quarry highlight the geology of the Kishwaukee area. Flora Prairie in Boone County has dolomite out­crops. Harvard West Geological Area in McHenry County has an example of pitted outwash plain while Harvard East Geological Area is an example of a moraine protruding down a valley.

The archaeological data base for the Kishwaukee River basin indicates that the region was continuously occupied for the last 12,000 years.

A total of 560 archaeological sites have been recorded for the Kishwaukee area and range in age from Paleo-Indian (10,000 B.C.) through the Postwar Industrial period (1946 AD.).

Since 1870 the population of the four main counties - DeKalb, McHenry, Boone, and Winnebago ­through which the Kishwaukee River flows has grown fivefold.

Five percent of the state's population is located in this area; population density ranges from 492 per­sons/square mile in Winnebago County to 109 persons/square mile in Boone County.

Nearly 11 % of the land is devoted to urban uses and four-fifths of the residents live in urban areas.

During 1970-1994, the area experienced a higher employment growth rate than the state as a whole - 1.9% average growth.

The area supports a diverse economy with manufacturing, construction, transportation, communi­cations, agriculture, higher education and mining.

Boone County was the first and McHenry County was the third to organize county Farm Bureaus or Soil Improvement Associations, as they were called earlier.

Like the statewide average, 79% of the land in the four-county area is considered agricultural.

DeKalb County is often in the top ten counties in the state for production of corn and soybeans.

McHenry County is the state leader in pounds of raspberries produced and in the number of acres
planted in tomatoes. It also ranks third in the state in the amount of acreage in orchards and is in the top ten counties for the number of apple trees.

Boone, McHenry, and Winnebago counties are often in the top ten for milk cow inventories. McHenry County also has the largest inventory of horses and ponies in the state and is one of the top producers of mink pelts.

Conservation districts offer several forest preserves and trails to explore the natural beauty of the area. The Long Prairie Trail is a 6.5 mile trail that traverses much of the old prairie landscape.

In 1820, prior to European settlement, about 74% of the Kishwaukee River area was covered with forest,
while prairie covered 26%.

Presettlement vegetation maps infer that savanna was the major vegetation type in the eastern part of the area, giving way to forest in the west. As the terrain becomes flatter towards the southwestern part, landscape scale fires had few natural barriers, and, as a result, prairie was the dominant habitat.

Wetlands covered as much as 31% of McHenry, 21% of Boone, 14% of Winnebago, and 4% of DeKalb County.

Present estimates indicate that McHenry County has the highest amount (6.2%) of wetlands, while DeKalb has the least (1.0%).

Only 22 acres (.01%) of high quality prairie and 39,430 acres (5.1 %) of forest remain in the Kishwaukee River area.

One federally-threatened species, the prairie bush clover, occurs in the Kishwaukee River area.

Twenty-one percent of the area's plants have been introduced from other geographical areas and have become naturalized. Exotic, invasive species include garlic mustard, purple loosestrife, and Canada thistle.

At least 262 of the 299 bird species that regularly occur in the state can be found here. Of these 262, 135 breed or formerly bred in the area, including 14 state-threatened and - endangered species.

Exner Marsh and Kloemphen Marsh, natural areas in McHenry County, have several rookeries of great blue herons; they also have records of the state-threatened pied-billed grebe, king rail, common moorhen, veery, and yellow-headed blackbird, and the state-endangered least bittern and sandhill crane, breeding there.

Seventy-four percent of the state's mammal species are likely to occur in the Kishwaukee River area. The rabbit, woodchuck, and skunk are still numerous, and deer have been successfully reintroduced.

Increased discharge is causing erosion problems along the Kishwaukee River and its drainage, especially on sloping land along stream valleys and moraines. Channel widening and bank failure are two of the major erosion problems.

The loss of natural habitat in the Kishwaukee River basin has been severe. Trends indicate that habitat losses and degradation of prairie and wetlands in the area appear to be about the same as rates for the state as a whole, while rates for forest and savanna loss are greater than statewide trends.

Only 52 acres (.006% of total area) remain in high quality, unde­graded condition.

Wetland conservation would help protect the large populations of state-threatened and - endangered species found in the area's dwindling wetlands.

Grassland restoration and wooded buffer strips around existing wetlands would provide habitat for
declining grassland birds, help buffer wetlands from surrounding development, and provide nesting habitat for many wetland species.

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