Illinois Dunesland Preservation Society - Biodiversity

Protecting the Nation's First State Dedicated Nature Preserve
Protecting the Nation's First State Dedicated Nature Preserve
Illinois Dunesland Preservation Society - Protecting the Nation's First State Dedicated Nature Preserve
Illinois Dunesland Preservation Society - Protecting the Nation's First State Dedicated Nature Preserve

Illinois Dunesland Preservation Society

The soil of the Dunesland is sand, coarse, and pebbly on the beach, but finer and mixed with increasing amounts of organic matter farther from the lake. Along the shores of Dead River and in the sloughs, generations of decaying plants and animals have been added to the sand. The sand of the dunes and interdunal ponds is slightly alkaline. It becomes less so as the oak zone is approached.

The soil of the Dunesland, like that of the rest of the Chicago area, is one of extremes. Winter and summer gales sweep across the beach and dunes, eroding the shore and moving the sand. Zero and sub-zero temperatures in the winter, and in the summer, a sun which can raise the temperature of the sand to over a hundred degrees, make it impossible for any but hardy species to survive. Except in the oak zone, the light is intense.

Lake County is located about a hundred miles from the apex of the great prairie or grassland triangle whose broad base extends to the Rocky Mountains. Before white man cut the forest and plowed the land, a maple-basswood-coniferous forest lay to the north of the Dunesland and a rich mixed deciduous forest lay to the south and east while to the west lay the prairie. Lake County is therefore, a region where in the past, extensive and stable plant associations merged. Where rainfall, lakes, and rivers provide enough moisture, trees, shrubs, and many kinds of herbaceous plants formed a dense cover. Where there was not enough moisture or where repeated fires killed the seedling trees, a tall-grass prairie with sod-forming grasses and myriads of forbs formed the dominant vegetation. Thus, the proximity of the Dunes to such a wide variety of plant types and the numerous habitats available to them made it possible for a large number of plants to invade the area and, provided they were hardy enough, to become established. Almost yearly fires have prevented the growth of trees in the prairie part of the Dunesland, thereby causing the prairie to flourish through lack of competition with woody species and alien weed species and through the release of nutritive materials from the burned plants. Most Eurasian weedy species cannot compete with undisturbed native, sod-forming perennial grasses, and the fires which usually come early in the spring are more apt to kill the early-seed-forming annual weeds that the later-seed-forming or perennial native species.

The kinds of plants that are found in any region, therefore, depend upon such physical factors as soil types (sand, gravel, clay), chemical nature of the soil (acid, alkaline, neutral), moisture, wind, relative humidity, temperature and amount of available light. In addition, their presence depends upon such biological factors as the nature of the past and present adjacent populations and upon the ability of the plants to spread by seed dispersal or by other means, including transportation by man or other animals. The make-up of a plant community is also determined by the ability of its component species to reproduce successfully and to compete successfully with other species for space, moisture, light, and nutrients. And finally, species must be able to withstand man – his roads, paths, vehicles, camp grounds, picnic areas, and litter.

To illustrate this principle of maturation of plant communities, or ecological succession as it is technically called, let us walk from the shore to the prairie, noting the difference in the habitats and in the kinds of plants that we find in them. At the water’s edge where waves are constantly moving the sand and pebbles, no plant can gain a foothold. Up a few yards from this storm beach, a few plants can survive. But here on the upper beach, lack of humus, excessive exposure to sun, wind, and blowing sand cause all but the best-adapted pioneers to die.  

We find some inconspicuous plants on the upper beach. Examples are Sea-Rocket, Seaside Spurge, and some larger ones such as Wormwood and Cocklebur. Farther from the shore, we find several grasses – Sand Reed, Lyme Grass and Little Bluestem – which because of their deep roots or underground stems – are able to maintain themselves year after year, thus acting as “sand fences” or sand-binders, stopping the blowing sand and thereby building up small dunes (the foredunes) around their bases. These grasses give some shade and protection from sun and blowing sand to a few insects and spiders and to some flowering plants, among them the Beach Pea and Hoary Puccoon.

Flora   |   Fauna   |   Endangered Species   |   Trail Walks

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To the west, over the edge of the foredunes, where there is more protection from the wind where even the stormiest waves do not reach, the environment is not so difficult and more kinds of plants can live. And yet, these rear dunes with their small amount of humus, high summer temperatures, and cold winter winds present formidable problems to plants. It is here that we find such characteristic Dunesland plants as Horizontal Juniper, Bearberry, Sand Cherry, Puccoon, Starry Solomon’s Seal, Prickly Pear Cactus, as well as Little Bluestem, Canada Wild Rye, and Sand Reed Grass. Both Horizontal Juniper and Bearberry are excellent sand binders. Their woody branches grow out over bare sand, thus preventing its blowing and also providing shade for other plants. As the leaves of these and other plants die, more humus is added to the soil. If we compare the size of the individual sand grains in the rear dunes with those of the storm beach, we find that the wind-blown sand grains of the rear dunes are smaller and smoother. In addition, the sand is darker in color due to the presence of some humus.

As we walk further from the lake, leaving the rear dunes, we come to a zone of oak trees which further help to stabilize the dunes. Black Oak and Choke Cherry are the characteristic plants, but there are many others: New Jersey Tea, Poison Ivy, Wild Grape, several grasses, among them the native June Grass and the Weedy, non-native Canada and Kentucky Bluegrasses. Numerous showy flowers are found in the openings in the oak woods. Coreopsis, Lupine, Butterfly Weed, Western Sunflower, Showy Goldenrod, Sky-blue and Heath Asters are here in profusion. More animals will be seen and heard now – Chipmunks, Ground Squirrels, Gray Squirrels, Blue Jays, Towhees, several kinds of Sparrows, to mention only a few.

Still farther to the west, the oaks stop rather abruptly and the prairie begins. If we stand on a small dune west of the oaks and look westward, we see the prairie divided into north-south strips, dry sandy prairie alternating with wet, marshy prairie or sloughs. Dead River flows nearby. Here in the prairie, we find the greatest variety of flowering plants. From May to October, the color of the prairie changes almost weekly as different flowers start their blooming season. Characteristic of the dry, sandy prairie are Sandwort, Spiderwort, Prairie Phlox, Black-Eyed Susan, Yellow Coneflower, Lead Plant, Purple and White Prairie Clovers, and Rough Blazing Star. Characteristic of the moist prairie are Grass Pink Orchid, Marsh Phlox, Shooting Star, Marsh Blazing Star, Boneset, Swamp Milkweed, Fringed Gentian, Sawtooth Sunflower, and Sneezeweed. (There are many more, many beautifully illustrated and described in Dr. Lunn’s book.)

The prairie we are looking at probably represents a mature or stable association, given the conditions that exist now – the frequent fires, the present drainage system, and the interference of man. If these factors should change, one might predict the development of a deciduous forest where we now see the sandy ridges and sloughs.

For all of the reasons mentioned above – its geology, its great variety of plants, its clear-cut picture of ecological succession and its uncertain future – the Dunesland is an extraordinarily interesting and challenging region.

Excerpt from Plants of the Illinois Dunesland by Dr. Elizabeth T. Lunn

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Illinois Beach State Park has a rich variety of life in various habitats throughout the park and dedicated nature preserve. The park is one of the primary birding sites in the state, making it very popular for bird walks as illustrated on this list, Birds of Illinois Beach. The varied habitats make for total fascination for bird lovers. Illinois Beach State Park Hawk Watch operates in the North Unit of the Park. Join them for a very rewarding experience. Fabulous birding experiences await the dedicated urban birder, especially in spring and fall when migratory throngs invade the park and lakeshore. The park area boasts untold opportunities to observe untold species.

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Lake County is the habitat for more endangered and threatened species than any other county in Illinois and has the largest undeveloped coastal habitat in Illinois. There are fourteen high quality natural communities, at least thirty-one state-listed endangered and threatened species, and habitat for four federally endangered species.

The Endangered Species Act of 1973 makes it illegal to take, harass, or harm animals and plants that are on this list and their habitats. Penalties for violation range up to $100,000.  Poaching is a very serious problem. It is important for concerned citizens to turn in poachers.

Illinois Beach State Park is home to the highest number of species on the list in this county. The USDA Illinois list of threatened and endangered plants can help guide you as to the status of plants you identify at the park. Many endangered and threatened plants and animals can also be found on the Wetlands list.

We will share two high profile representatives on this site:

The cirsium pitcheri/Pitcher’s Thistle is a very rare thistle that grows on the sandy shores and dunes of the Great Lakes. There have been efforts to reintroduce it to the park by the U.S. Fish and Wildlife, but is still considered threatened. The plant must grow for 5-8 years before it finally flowers. The seed germinates in June, then flowers and fruits from late June until early September. It attracts up to thirty different insect species with its beautiful cream or pink blossoms.

The Piping Plover became protected by the Endangered Species Act on January 10, 1986 as Endangered. It is a small sand-colored bird that resembles the killdeer. The adults have a prominent black neck ring, bright yellow-orange legs, and a black crest on the forehead. They easily blend into their surroundings, making them difficult to see. They are named for their distinctive high-pitched calls that sound like a bell or whistle.

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A good place to start a walk is at the now-shuttered Interpretive Center. It is occasionally open on weekends and staffed by volunteers. Please see the park map for to find it. It is called the “Visitor Center” on the map.

Park Etiquette:

1. Please be respectful of the habitats you will visit and stay
   on the trails so you don’t trample any plants.
2. Report harm online to endangered or threatened
    species or habitats or call 1 877 236-7529.
3. Please do not collect ANYTHING so it will be there for others to enjoy.
4. Natural beauty is spoiled by litter. Please carry your trash back to the cans in the parking lot.
5. Please don’t smoke. Remember, as Smokey says, “Only you can prevent forest fires.”

Dunesland has several pamphlets that we have developed for guided walks. These pamphlets are from Dunesland’s archives and have not been reproduced in many years, but you have the ability to download them from this site before you go to Illinois Beach. They were produced on a typewriter, so you will be able to see some evidence of strikeovers which younger hikers may not have seen! We also plan to make available out-of-print guides from the state. Due to budget cutbacks, very little of their information is available.

An excellent overview of the park before you visit is the state’s pamphlet, An Interpretive Trail System written by former park staff members many years ago. It will help you to understand the geomorphology of the park and the very special habitats that you will see.

Let’s start with A Special Walk in the Dunesland, which is a lovely beginning. This walk is an introduction to the ecological succession at the park through a beach, prairie, open oak forest, along a swale, and over the dunes to the Dead River. Please note that in the pamphlet directs you to begin in front of the Holiday Inn, but that is now called the Illinois Beach Resort and Conference Center where Dunesland meetings are usually held. It is a lovely place to stay. If you click on the link, you will find directions to the resort.

July Along the Dead River actually includes wild flowers, trees, and shrubs that are in bloom or of particular interest in late May and early June. This walk begins in the southwest corner of the Interpretive Center parking lot; there is a brief description of the flowering plants at each stop. Further information may be found in the book Plants of the Illinois Dunesland by Dr. Elizabeth Lunn. The one mile Dead River Trail   pamphlet covers the same territory but from a slightly different perspective. This walk’s emphasis is not focused only on the flora of the area, but also the fauna.

The Bob-O-Link Prairie Trail begins in the southwest corner of the Interpretive Center parking lot. It is only .4 mile, but there are many interesting specimens to view.

If you have information that you would like to share, please contact us. Additional information and brochures will be posted as time permits, so please visit this site again!

In nature, large plant associations covering many square miles, or small plant communities covering only a few square yards, do not come to maturity suddenly. Only on a farm or in a garden where man has deliberately planted and nurtured the assortment that he wants do we find ready-made communities. In nature, communities develop slowly through many years, such as a town might develop from a small pioneer settlement through a long history of gradually changing populations, industries, and businesses until a more or less stable city emerges. Eventually, such a city or plant community may come under adverse internal or external pressures which may cause it to change or die.

Coneflowers

Queen Anne's Lace

Killdeer

Early Wild Rose

Fringed Gentian

Sentinel Near Dead River Trail

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