Dixon Prairie begins and ends with savanna - a type of prairie that lies between the edge of a forest and the wide-open grasslands. While most prairie is treeless, the savanna is scattered with trees - often fire-resistant bur oaks - that cast partial shade on the otherwise sun-baked landscape. Beneath the trees is an entirely different community of shade-tolerant, flowering plants.

Rich, dark, well-drained soil characterizes a mesic prairie. The soil is the result of thousands of years of prairie vegetation and roots growing and decaying over time. The word "mesic" refers to the moderate amount of moisture in the soil. In such ideal conditions, grasses and prairie plants grow taller than a person above ground and have roots systems that delve deep into the soil underground.

In summer, look for the compass plant, which turns its big leaves to avoid the midday sun.

Picture low sand dunes undulating down to the water's edge. That's the topography of a sand prairie. At the top of the dunes, dry prairie plants flourish, while wet prairie plants gain a foothold closer to the shoreline where groundwater levels are higher.

Fens are rare. They're wetland prairies that are fed by the steady seepage of groundwater from surrounding gravel hills. Here the water contains a high degree of mineral salts leached from underground limestone, and the soil is cold, waterlogged, and mucky.

Gravel hill prairies formed as glaciers receded, leaving behind heavy piles of gravel and sand. Water drains quickly through this rocky soil, so the plants adjust accordingly: they grow less tall to avoid the wind and heat, but put their energy into well-developed root systems that maximize the meager water supply.

The boardwalk offers a beautiful view of the lakes and prairie in every season.

-In spring, the action's in the sky, with wave after wave of migrating birds.
-In summer, the prairie plants power up, eventually growing taller than a person.
-In fall, the grasses go golden and birds flock here to eat and rest on their way south.
-In winter, open water attracts overwintering birds and animals.

Wet prairies formed throughout northeastern Illinois in areas where drainage wasn't good. Water typically accumulates during spring and autumn, and the soil remains moist even during the hot summer months.

Marsh Island is situated in a low-lying part of the Garden that can be inundated with water in rainy seasons. Plants that grow here are rooted in underwater soil. Frequent visitors to the island include marsh-dwelling birds such as Virginia rails and sora.

Dixon Prairie is a haven for all sorts of birds (and the birdwatchers who can spot them). At this close-to-the-water path you may see mallard ducks, egrets, herons, and, on the mud flats, terns and sandpipers. In the mesic prairie and savanna, watch for the undulating flight patterns of goldfinches and for red-winged blackbirds perched atop the tall plants along the paths.

We recommend taking a bench break and listening for birdsong here.

For more bird watching info, use the Birding Walk.

Often the lone tree on the savanna, the bur oak survived frequent prairie fires because its corky bark is fire resistant.

Fire is essential to maintaining the prairie. While lightning once sparked prairie fires, we burn sections here intentionally each spring and fall. Fire prevents woody shrubs and trees from getting established and recycles nutrients back into the soil. Because prairie plants (and bur oaks) have exceptionally deep roots, they are able to regenerate year after year.