Summer 2007
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Woods of Wisdom

Summer 2007

"All ethics so far evolved rest upon a single premise; that the individual is a member of a community of interdependent parts.  The land ethic simply enlarges the boundaries of the community to include soils, waters, plants and animals, or collectively, the land ... a land ethic changes the role of Homo Sapiens from conqueror of the land - community to plain member and citizen of it ... it implies respect for his fellow members, and so also respect for the community as such."

                                                                                                        --- Aldo Leopold, "Sand County Almanac"




photo credit:


By Edgar Fawcett

I saw, one sultry night above a swamp,
The darkness throbbing with their golden pomp

And long my dazzled sight did they entrance                                                

With the weird chaos of their dizzy dance!
Quicker than yellow leaves, when gales despoil,
Quivered the brilliance of their mute turmoil,
Within whose light was intricately blent
Perpetual rise, perpetual descent.
As though their scintillant flickerings had met
In the vague meshes of some airy net!
And now mysteriously I seemed to guess,
While watching their tumultuous loveliness,
What fervor of deep passion strangely thrives
In the warm richness of those tragic lives,
Whose wings can never tremble but they show
Those hearts of living fire that beat below!


Study Finds Illinois is Far Behind in Open Space Protection

The following is an excerpt of an article by Beth White, written for The Trust for Public Land

Illinois ranked in the bottom third of states in spending for open space, and dead last by a wide margin in the Midwest in state-owned protected land, according to Illinois State Land Conservation Funding, a report released today. The report was prepared by the Illinois Environmental Council Education Fund (IECEF), The Nature Conservancy and The Trust for Public Land, Illinois, with the generous support of the Doris Duke Charitable Foundation.

Illinois has gone from spending an average of nearly $50 million a year on open space acquisition in the early 2000s to averaging less than $10 million annually over the last few years.

To begin to address an estimated need of $3 billion to protect and maintain Illinois' natural areas and parks, the Partners for Parks and Wildlife (PPW) calls for at least $100 million in new funding annually by the state and a commitment to fully fund existing programs at approximately $50 million a year.

"Illinois has not invested sufficiently in protecting open space for parks and natural areas. The state needs to make a commitment to save our open land and preserve our natural heritage for Illinois' future generations," said Jonathan Goldman, the Executive Director of the Illinois Environmental Council Education Fund (IECEF), which authored the report in partnership with The Nature Conservancy and The Trust for Public Land.

bulletIllinois has lost more than 90 percent of its original wetlands, 99.99 percent of its original prairie, and currently has 424 state and 24 federally listed threatened and endangered species within its boundaries.
bulletIllinois ranks last by a wide margin among Midwestern states in acres protected per capita, with only 1 percent of its land owned by the state.
bulletIllinois spent $2.67 per resident on open space annually during its peak years of investment, while Ohio spent $4.36, Minnesota spent $5.76 and Wisconsin spent $9.80. Funding in Illinois has since dropped by about 80 percent.

Parcels of open land are getting more expensive as real estate values rise, and many are lost to development. The report shows that rural farmland real estate prices have risen 68 percent statewide from 2000 to 2006, and in places like Chicago's collar counties, development is happening at a ferocious rate.

Illinois' drop in funding is the result of the end of a four-year program to protect open space and diversions of funds from two long-term programs, the Open Space Lands Acquisition and Development Fund (OSLAD) and the Natural Areas Acquisition Fund (NAAF). Both OSLAD and NAAF are supported by dedicated funding from the Illinois' Real Estate Transfer Tax (RETT).

"But while that revenue has increased with the real estate boom, the state has taken away millions of dollars slated for parks and natural spaces through budgetary procedures. In fiscal year 2006 alone, more than $35 million was diverted," noted Lenore Beyer-Clow, Policy Director from Openlands.

"When the laws were written, funding for these open space programs was tied to the real estate market, so that when land starts being increasingly developed, more resources are available to create parks and save habitat. This was well-crafted legislation based upon sound public policy. We need to restore our commitment in Illinois to using these funds only for protecting natural areas and creating new parks and playgrounds," said Beth White, Chicago Area Director, of The Trust for Public Land.

Contact: Beth White, The Trust for Public Land, 312-427-1979 x101

With reliable state funding, Illinois can begin the process of acquiring important parcels of land before the cost becomes prohibitive or the opportunities are gone.

Partners for Parks and Wildlife is a grassroots coalition working to secure and increase funding for open space and park acquisition, natural area preservation, wildlife habitat protection and recreational opportunities in Illinois. PPW was created in 2004 when more than 130 organizations came together to advocate against state funding cuts for open space.

Check out the website for Partners for Parks and Wildlife:



Kankakee River Valley – A Local Treasure

The following is an excerpt of an article written for Chicago Wilderness:

The Kankakee River Valley contains a great diversity of natural communities, including various types of forests, savannas, prairies, wetlands and waters. Each type of community has its own unique set of living things, dependent on specific physical conditions. For example, prairies are grasslands that develop on flat lands where occasional fires shape the treeless landscape. The Greater Chicago region's remaining prairies harbor colorful wildflowers, a great variety of grassland birds, and were once home to great herds of America Bison. Savannas are grasslands with some trees. Birds such as eastern bluebirds and red tailed hawks prefer to nest in the open savannas. Other creatures, such as gray squirrels and hairy woodpeckers are more at home in denser, shadier forests. Creatures such as beavers and great blue herons depend on wetlands for their survival. To find out where to go to see examples of the various types of natural communities, go to Things to See in the Explore Chicago Wilderness section of the Chicago Wilderness Web site:


To read detailed descriptions of the various types of communities, go to this link on the website:

The Kankakee River Valley lies at the southern perimeter of the Greater Chicago Region, the Kankakee River State Park being perhaps our most widely-known and appreciated natural treasure. Another unique and lesser known example of the rich biodiversity in the Kankakee River Valley is the Mskoda Sands preserve in St. Anne Township. This preserve is part of the Kankakee Sands region in the eastern portion of the county. Kankakee Sands takes its name from its sandy soils, which support globally significant oak barrens, prairies and sedge meadows. This region offers rich habitat for birds and small animals. The Mskoda Sands preserve contains some of the best examples of black oak barrens in the Midwest. Unspoiled sand dunes and swales stretch as far as the eye can see.

The Kankakee Sands region presents an unequalled opportunity to protect a naturally functioning landscape, which remains almost unchanged since pre-settlement times. Prior to European settlement, oak savanna covered about 27 to 32 million acres of the Midwest. By 1985, only 113 sites containing 2,600 acres remained. Development has dramatically impacted the natural processes needed to maintain quality oak savanna ecosystems, making all the more important the preservation of what remains.

To learn more about the Mskoda Sands preserve, and its plant and animal life, visit this link:

Another wonderful area to visit is the Iroquois Woods Nature Preserve in northeastern Iroquois County, a forest remnant of the mesic upland forest that was formerly abundant along the Iroquois River. The most common trees in the overstory are red oak, white ash, basswood, and sugar maple. The common understory trees and shrubs are pawpaw, ironwood, and small-stemmed individuals of the canopy species. A well developed understory containing Canada nettle, water-leaf, fragile fern, grape fern, and sensitive fern is present. This is the best old growth forest remnant along the Iroquois River.


What is Biodiversity?

"Biodiversity" means biological diversity. It describes the variety of all the genes, species and natural communities that exist within a particular place.

Diversity of Species

Healthy natural habitats generally have more biodiversity than damaged or degraded ones. For example, a healthy oak woodland would typically include tens or hundreds of plant species as well as habitat for hundreds or thousands of species of birds, mammals, reptiles, amphibians, insects, and other living things. A degraded oak woodland that has been damaged by overgrazing or fire suppression would have fewer varieties of plants and animals. It would have some of the same species, but in smaller numbers. It might still be an important natural community but the biodiversity of the degraded woodland would be lower than that of the healthy woodland. In even greater contrast, a soybean field that has soybeans and a few weed species, the occasional insect, and no nesting birds has exceptionally low biodiversity.

Rattlesnake Master                                  

Eryngium yuccifolium                               

photo by Theodore S. Cochran                      

Diversity of Natural Communities                                                                                                                                                                                                                                             

Within a region the size of the greater Chicago area, another way to measure biodiversity wealth is by the number and variety of natural communities that exist side by side. For example, the 3500-acres in the Kankakee River State Park contain many types of natural habitats. This variety of natural communities contributes greatly to the high level of biodiversity in the area -- communities of plants and animals that are rare worldwide, and that depend on natural areas for continued survival.

Nature needs biodiversity

Diversity is important to the health of natural systems because the plants, animals and other life forms in any given ecosystem have adapted to living together over thousands of years. Each species plays a role in its ecosystem, and the loss of a seemingly unimportant creature could affect the entire system in ways that people cannot predict.

Biodiversity is also important because it works like nature's insurance policy. Ecosystems that contain a variety of life forms tend to recover from stresses like natural disasters, human disturbance, or invasive species more easily than less diverse ecosystems.

People need biodiversity

People benefit from protecting biodiversity because healthy, diverse ecosystems provide essential services. They hold plants that produce the oxygen we breathe, insects that pollinate our food crops, and species that could hold clues for medicine. In fact, almost half of our prescription drugs are based on natural products.

Healthy natural areas benefit the people who live here by improving water quality and reducing the risk of flood damage. Wetlands and other natural areas along the edges of streams, rivers and lakes help protect and improve water quality by trapping sediments, and by absorbing or breaking down pollutants. They also serve as land where floodwaters can collect, helping prevent the destructive and expensive flooding of homes and businesses.

Our region contains an unusual variety of types of natural communities. These areas harbor many rare or endangered species of native flora and fauna. The variety of living things are a source of wonder and inspiration, and it is our responsibility to protect this amazing diversity of life for the benefit of future generations.

People value healthy natural places for their beauty and their ability to inspire us. Nature can offer reprieve from the stress of urban life. Access to nature is an important aspect of quality of life; the presence of safe parks, paths for hiking and biking, and forest preserves are priceless treasures for our community.

Threats to Local Biodiversity

A variety of factors put stress on the diverse life forms that inhabit our area. Perhaps the greatest threats to our natural heritage include poorly planned development, invasive species, land management challenges and pollution.

Poorly Planned Urban Development

The rapid development of land for urban uses is the primary threat to the remaining unprotected natural lands of our region, and in some cases it is causing serious degradation of protected lands as well. Development affects natural communities in many ways. Urban development increases the amount of paved surfaces, which alters the natural flow of water across the landscape (because the water is not absorbed where it falls). This changes the structure of wetlands, streams and rivers, and reduces water quality by allowing more silt and chemical pollutants to reach our waters. The design of sprawling developments reduces air quality because it forces people to drive more than they might in well-planned communities. The more time we spend in our cars, the more air pollution we produce. Sprawling development also breaks natural areas into small fragments. This is a problem for animals such as grassland birds that can only breed successfully in large continuous habitats. Urban development can further threaten biodiversity by disturbing natural cycles. Many of our region's natural communities are adapted to periodic fires and they depend on fires to maintain the health of the ecosystem. As development encroaches and breaks natural areas into small parcels, people stop this natural cycle.

Invasive Species

Invasive, non-native species are a threat to almost every type of natural community in our region. Invasive species are non-native ones that people have intentionally or accidentally introduced to our region. Most non-native species are not invasive, but those that are spread out in their new environment and virtually take over. They alter the balance of natural communities, crowding out native plants and animals that have lived together for thousands of years.

Invasive species can wipe out many native species and greatly reduce the biodiversity of the ecosystems they invade. Particularly problematic invaders include buckthorn, Asian honeysuckle and garlic mustard, which are reducing the diversity and health of local forests and savannas. Plants such as leafy spurge, reed canary grass, and purple loosestrife have invaded local prairies and wetlands, while thumbnail-sized zebra mussels compete with native aquatic creatures for food and space in the region's waters.

Land Management Challenges

People have altered many of the natural areas in the Chicago Wilderness region, reducing their ability to support diverse plant and animal communities. These systems will only recover if people help restore them to health. Managing and restoring our natural resources can be an extremely challenging process, but one worth undertaking. Healthy natural areas increase air and water quality, reduce flooding, produce oxygen, and support an abundance of life.


Pollution is particularly problematic for the waters of the Chicago Wilderness region. Storm water that runs off the roofs of buildings, paved surfaces, and chemically treated landscaping picks up pollutants along the way. Runoff from residences, lawns, businesses, construction sites, and industries carries sediment, nutrients, pesticides, metals, grease, oil bacteria, salts and debris to nearby streams. Runoff from agricultural areas carries similar pollutants but in different concentrations. "Point sources," where pollution flows from a single source, include municipal wastewater treatment plants and sewer overflows. People have managed to make dramatic reductions in these point sources of pollution during the past two decades. However, a major challenge for the future will be to reduce the impact of development-related runoff.


What You Can Do

To preserve and protect wildlife is to build a relationship with wildlife. Realizing the benefits nature brings to our earth and to our own lives sets a foundation for this relationship. Spread the word about your experiences with nature and wildlife. Tell your family, your friends and your neighbors how they can benefit too.

Education Is Key

Educate and become educated on ways to coexist with wildlife. A number of programs and classes are out there that can teach you about landscaping for wildlife, how to identify valuable species in your area and around the world, the differences between native and non-native species and the natural resource management tools that are implemented everyday to restore wildlife populations and habitat.

Become a volunteer

who works with land managers and other volunteers to maintain and restore the quality of natural areas.

Restoration workdays and other volunteer events are a staple in many parts of Illinois. Participate in brush cutting and help eliminate weedy buckthorn. Restore prairies, wetlands and woodlands by taking part in a group collecting native seeds, or planting of native trees, shrubs and other plants. Help guide a bird walk and point out warblers, tanagers, hawks, mallards and more. Or assist others in identifying local flora and fauna on a nature walk. Volunteers are some of the best people you will ever meet, and the opportunities are endless. Contact your local conservation organizations to get involved in activities and learn about citizen stewardship of our natural areas.

Create A backyard habitat with native plants.

Plants and flowers that are native to the region can thrive without the use of polluting pesticides and fertilizers, and they often need less watering than non-native plants.

Learn how you can create your own backyard habitat. Explore ways to share land with wildlife and revel in the joy and value it brings to your life. Remember not all creatures are warm and fuzzy, but even the smallest beetle can keep crop-damaging pests out or your garden. Check out this link (which includes a native plant list with photos and planting information) to create your own backyard habitat:



Reduce, Reuse, Recycle and Invest

It's as simple as one, two, three and even four. Americans generate more waste year after year and landfills are reaching their maximum capacities. Not only is growth and development encroaching on wildlife habitat, waste is taking its toll too. Simply reducing consumption can benefit wildlife habitat and human habitat. Consume and throw away less and buy longer lasting, durable products. Reuse items by repairing them, donating them or selling them so you don't have to throw them away. You can reuse an item for the same purpose you bought it for or find other creative ways to use it. Milk jugs make great watering containers for your household and garden plants. Recycling has been one of the most successful ways of diverting waste from landfills and incinerators. It turns materials that would otherwise be waste into valuable resources that generate a variety of environmental, financial, and social benefits. Lastly, a number of ecologically responsible companies have established funds that you can contribute to. Search out companies that have been given the "green" stamp of approval for your investing choices.

bulletReduce the use of pesticides and fertilizers on your property, and avoid planting invasive species such as purple loosestrife.
bulletParticipate as a citizen advisor in the development of municipal, county and regional plans, and raise issues regarding biodiversity conservation.
bulletBe an advocate for biodiversity with local officials as well as with state and federally-elected representatives, and support legislation and programs that protect and acquire natural lands.
bulletBecome a citizen scientist by learning to observe plants and animals and collect information that will be used by local scientists and land managers.
bulletJoin and support conservation organizations.
bulletGet your children involved by participating in nature classes and activities.
bulletShare what you know about the importance of nature and biodiversity with others.


"We are not conserving nature to show we can have a lot of species locked up in some museum display case for everyone to view. We protect nature for people."

Peter Kareiva
Chief Scientist
The Nature Conservancy

Butterfly Weed

Photo by Merel R. Black

Milkweed Family

Family Apocynaceae

Asclepiadoideae (sub family)

While the Common Milkweed is familiar to most, and will grow in open disturbed areas throughout the greater Chicago region, there are a number of other milkweed plants (Asclepiadoideae) which are little known by the general public, and which are found in more narrowly defined habitat types. For some species, reduction of Illinois prairie ecosystems to less than 1% of its former extent has qualified the species for listing as endangered in Illinois. Aslcepias meadii (Wooly Milkweed), is also on the federal list of threatened species.

Milkweed is typically insect pollinated, and many insects such as the Monarch butterfly are dependent on milkweed. Loss of milkweed species not only indicates degradation of natural ecosystems, but also threat to associated species as well.

Asclepiadoideae in the greater Chicago Area

Name of Milkweed found in the Chicago Region Habitat Illinois State or Federal threatened or endangered status
Sand Milkweed, Clasping Milkweed Asclepias amplexicaulis open, somewhat disturbed sandy areas  
Poke Milkweed Asclepias exaltata woodland or semi shade along roadsides  
Tall Green Milkweed Asclepias hirtella dry sand prairies  
Swamp Milkweed Asclepias incarnata wetland areas  
Wooly Milkweed Asclepias ontarioides (lanuginosa in Strunk & Wilhelm) gravelly morainic hills on prairie remnants State threatened
Mead’s Milkweed Asclepias meadii dry ground Federally endangered & State threatened
Oval Milkweed Asclepias ovalifolia dry sand prairies State threatened
Purple Milkweed Asclepias purpurascens mesic prairie  
Aquatic Milkweed, White Milkweed

Asclepias perennis

wetland areas  
Showy Milkweed Asclepias speciosa wetland areas  
Prairie Milkweed Asclepias sullivantii moist prairie  
Common Milkweed Asclepias syriaca Disturbed, unshaded areas  
Butterfly Weed Asclepias tuberosa dry sand prairie, well-drained prairie, and open savanna  
Whorled Milkweed Asclepias verticillata dry, unshaded uncultivated soils  
Short Green Milkweed Asclepias viridiflora dry sand prairies  


Whorled Milkweed

Asclepias verticillata

Photo by Emmet J. Judiewicz

Milkweed has recently been grouped into the family Apocynaceae, sub-family Asclepiadoideae. The old classification, Asclepiadaceae, is often found in books such as Swink & Wilhelm’s Plants of the Chicago Region, Audubon’s Field Guide to Wildflower, the USDA website, and other sources.

Syriaca (Common Milkweed) is perhaps the most familiar, and is found in 31 states in the United States, excluding Florida and the states west of the Dakotas, Kansas and Texas, excepting Oregon. According the United States Department of Agriculture, syriaca is considered weedy and invasive in the Northeast, Kentucky, Nebraska and the Great Plains USDA website).

Some interesting species in the greater Chicago region have some bearing on habitat quality and restoration considerations. These species are Asclepia amplexicaulis (Sand, or Clasping Milkweed), Asclepia exaltata (Poke Milkweed), Asclepia hirtella (Tall Green Milkweed), Asclepia purpurascens (Purple Milkweed), Asclepia sullivantii (Prairie Milkweed), Asclepia tuberosa (Butterfly Milkweed), and Asclepia viridiflora (Short Green Milkweed).

Asclepia amplexicaulis (Sand, or Clasping Milkweed) is found in dry sandy areas, often in sites with little vegetation and a history of disturbance. The flowers are pale greenish, with a single smooth erect to sprawling unbranched stem about 3’ tall. The leaves are up to 6" long and broadly oval, with wavy edges and heart-shaped or flattened bases. There is usually a single long-stalked flower head standing well above the leaves with a rounded cluster of greenish purple flowers. Each flower is on a stalk up to 2" long. The petals are greenish purple, reflexed, with 5 cuplike yellow to ping or purple hoods or horns.

Asclepia tuberosa (Butterfly Milkweed) is found in dry sand prairie, well-drained prairie, and open savanna. It is a sturdy plant up to 3’ tall, often sprawling or bushy. This milkweed does not have milky sap. The stems are covered by coarse, spreading hairs. The leaves are alternate, occasionally opposite along the upper stem, narrow, stalkless and lanceolate. Flower clusters arise where the leaf meets the stem, and each cluster is relatively flat compared to other milkweeds, consisting of up to 25 single, and individually stalked. Usually the flowers are bright orange; however the color can range from pale yellow to deep red. The seed pods are smooth and narrow, about 6" long (Ladd & Oberle 1995).

Asclepia viridiflora (Short Green Milkweed) found in dry or sandy prairies throughout the tallgrass region. It is not abundant at any single location, rather is found as widely scattered individuals. The plant is usually less than 2’ tall; the leaves may range from broadly oval to narrow, and usually have wavy edges. They may be arranged opposite or alternate, and may or may not have stalks. Rounded green flower clusters arise at the upper part of the plant from where the leaves join the stem. Usually more than 25 individual flowers form a cluster, each cluster on a stem less than 1" long. The flowers are about ½" long, consisting of 5 reflexed greenish petals with 5 erect pale hoods. The seed pods are smooth, narrow, and 6" long and less than 1" thick. The horn is absent in this species (Ladd & Oberle 1995; Missouri Plants website).

Asclepia hirtella (Tall Green Milkweed) is found in flat sandy prairie, glades and pastures. It may grow to a meter in height, with leaves dense on the stem and linear-lanceolate in shape. Although the flowers appear white from a distance, up close the petals are greenish-purple at the apex. The hoods are whitish with purple tinge at the base (Missouri Plants website).

Asclepia purpurascens (Purple Milkweed) occurs in rocky open woods & thickets, prairies, stream banks, wet meadows, and roadsides. It grows to 3’ tall with many pairs of large opposite oval leaves on stalks up to 1" long. There are one to a few rounded flower clusters. The petals are deep reddish purple, with 5 purple, reflexed petals flanking 5 purple hoods. The smooth seed pods are narrow and tapering, up to 6" long and 1" wide.

Asclepia sullivantii (Prairie Milkweed or Sullivant’s Milkweed) prefers full sunlight, a rich loamy soil, and moist to mesic conditions. This plant is far less aggressive than the Common Milkweed. Prairie Milkweed is very similar to the Common Milkweed except that it has slightly larger flowers that are usually more pink, the leaves are hairless on the undersides, the follicles are smoother, and it tends not to grow as tall . The leaves are thick and oval and stalkless with broad bases and pointed tips. One to several rounded clusters have up to 40 individual flowers each. Flowers are individually stalked and just under 1" long and ½" wide. Each flower has 5 reflexed deep reddish pink petals and 5 erect pink hoods. The seed pods are about 4" long and 1 ½" thick, and usually have soft, pointed projections on the upper half. The plant is listed as endangered in Wisconsin, Michigan and Minnesota.

Threatened species of Milkweed in Illinois

There are four species of Asclepidaceae that are threatened in Illinois, according the Illinois Natural History Survey. They are Asclepias lanuginosa (Woolly milkweed), Asclepias meadii (Mead's milkweed), Asclepias ovalifolia (Oval milkweed), and Asclepias stenophylla (Narrow-leaved green milkweed).

Asclepias stenophylla (Narrow-Leaved Green Milkweed), is not found in the greater Chicago region, but is found in rocky outcrop areas in west-central area of Illinois (INHS). Its synonymies are Acerates angustifolia, Polyotus angustifolius. Natural communities are upland forest, loess hill prairie, rocky limestone bluffs. The Illinois divisions where it occurs are the Middle Mississippi Border, the Glaciated and Driftless Divisions. Counties where it occurs are Adams, Calhoun, and Pike. In Illinois it is at its Northeastern range limit (INHS website).

Asclepias ontarioides is very rare, and typically found in the Chicago region on prairie remnants on gravelly glacial moraines. The synonymy of this plant (Wooly Milkweed) is Asclepias lanuginosa and is listed as such in Swink & Wilhelm and other sources. Illinois Natural History Survey describes the natural communities where this is found as dry upland forest, and dry and gravel prairie. It describes the Wooly Milkweed as at its Eastern range limit, and Illinois located in Boone, Cook, DeKalb, DuPage, Kane, LaSalle, McHenry, Ogle, Will and Winnebago Counties (INHS website). .

Asclepias meadii is also federally endangered, and in Illinois is extremely rare. Swink & Wilhelm report that it is known from a collection made by Brannon on July 3, 1888 in dry ground near Crown Point, Indiana. A discovery of this plant was made near Palatine in Cook County in 1966 by William Rommel. Dr. Robert Betz of Northeastern Illinois University has made an extensive study of his species and its ecology (Swink, 1979). The Illinois Natural History Survey lists the habitat types as mesic or dry prairie, savanna, in the Grand Prairie and Greater Shawnee Hills divisions. INHS reports the plant in Cook, Ford, Fulton, Hancock, Henderson, Peoria and Saline Counties.

Asclepias ovalifolia grew on dry, usually sandy prairies, dry upland forest, and dry savanna. Swink & Wilhelm reported that the plant is possibly now extinct in the Chicago area, who reported that they had not ever seen the plant, nor were they aware of any recent local collections. However, INHS reports the plant as threatened, but existing in Cook, Kankakee, Kendall, Lake, and McHenry counties.


Swamp Milkweed

Asclepias incarnata

Photo by Margery Melgaard



General Description of the Family

The features distinguishing the family Apocynaceae from other major families of Gentianales are the milky latex, an apically thickened style forming a stylar head; and ovaries usually distinct joined only by a common style or stylar head. Asclepiadaceae grow as herbs, shrubs or vines, usually with milky sap. Distinctive features are opposite or whorled leaves, flowers that grow in umbel-like clusters (cymes), and tufted seeds in pods.

Flower Structure

The flowers are radially symmetrical in flat or round clusters. There are 5 sepals and a corolla of 5 connate petals with reflexed lobes and a 5-lobed crown between the corolla and stamens. There are 5 stamens; all parts are attached at the base of the two ovaries. The leaves are simple, mostly paired or n whorls of 4. The fruit is two pods often joined at the tips by a style filled with many silky-haired seeds.

In Asclepiadaceae, the gynoecium is highly modified with separate ovaries and a differentiated stylar/stigmatic head. The plant structure is specialized for efficient pollination. These include a stylar head that is zonally differentiated, apical anther appendages, differentiation of portions of the anthers, and sticky hair pads on the style head or anthers. The flower structure is specialized for efficient pollination. These include a stylar head that is zonally differentiated, apical anther appendages, differentiation of portions of the anthers, and sticky hair pads on the style head or anthers. Like most species of Apocynaceae, Asclepiadoideae seeds have follicles with tufted, flattened seeds that are easily carried by wind when the seed pods open.

Pollen Biology

Many nectar gathering insects act as pollinators for the Apocynaceae family, including moths, bees, wasps, flies, and butterflies. The three-stepped structure of the flower has an important function in the plant’s pollination. The base zone of the structure forms receptive stigma at the base of the stylar head under a collarlike extension or ‘pollen scraper’. The middle zone produces sticky fluid. The apex of the stylar head produces the pollen which is deposited by the inward opening of the anthers surrounding the stylar head. The specialized pollinium forms a pollen sac that becomes a glutinous hardened mass attached to a translator arm.

Sacs of pollen snag on insects’ legs, are pulled from the stamens, and then must be precisely inserted in slits behind the crown of another plant. Nectar collects in the specialized stamen structures, called hoods or horns. When the pollinator seeks the nectar, pollen from a previously visited flower is scraped off and deposited in the stigmatic region. The pollinator contacts the sticky central region and then picks up pollen from the apical region of the stylar head.


            Foster, S. & Duke, J. (1990). Peterson Field Guide to Medicinal Plants - Eastern and Central

                    North America. New York: Houghton Mifflin Company.


  Illinois Natural History Survey Botany Collection website


   Illinois Wildflowers website.

   Jones, S. & Cushman, C. (2004). A Field Guide to the North American Prairie. Boston: Houghton Mifflin Company.

              Judd, W., Campbell, C., Kellogg, E., Stevens, P., & Donoghue, M. (2002). Plant Systematics, A Phylogenetic Approach

                   Sunderland, Massachusetts. Sinauer Associates, Inc.

               Ladd, D. & Oberle, F. (1995). Tallgrass Prairie Wildflowers. Helena, Montana. Falcon.

               Missouri Plants website.

              Niering, W.A. & Olmstead, N.C. (1979). National Audubon Society Field Guide to North American Wildflowers.

                        New York. Alfred A. Knopf.

                Swink, F. & Wilhelm, G. (1979). Plants of the Chicago Region. Lisle, Illinois: Morton Arboretum

                United States Department of Agriculture – Natural Resources Conservation Service website

                United States Geographic Survey; Northern Prairie Wildlife Research Center



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last updated on August 26, 2013