This re-publication reflects local conservation thinking 22 years ago - during the time of recovery from "The Moratorium". It includes hard-to-find info about some Northbrook forest preserves.
Friends of Northbrook Forest Preserves
Fourth Year Report
February 2001
The Friends of Northbrook Forest Preserves present this report to our neighbors, to all who are interested in the Northbrook forest preserves, and to the staff of the Forest Preserve District of Cook County. We work to support the staff and volunteer stewards who do so much to care for these lands, for the benefit of the native flora and fauna and for the people of Cook County. It’s a hard and important job. We also believe that as neighbors and users of the preserves we have a special responsibility and opportunity to help out and, to that end, this report summarizes out first four years of work.
This report is an informal one. Below we pull together various kinds of information and tell stories that we hope you will find interesting. We are always looking to empower other people who might like to help in any way. If you are interested in the forest preserves, please join us. We sincerely thank one and all for work and support to date, and for your interest in one of Northbrook’s most important assets, our forest preserves.
Heritage and fire
By Jay Risk
When I was growing up in Lake County in the 50’s and 60’s I dreamed of hiking the slopes of Mount McKinley in Alaska and canoeing the wilderness rivers of the Quetico in Ontario. I had no idea about the priceless natural heritage in my own backyard. I took the trillium under the oaks and the big bluestem grasses of the prairie for granted. Now, at the turn of a new millennium, I have discovered the globally rare wonders of Chicago Wilderness and the Cook County Forest Preserves. I have treasured showing my son the Cooper’s Hawk nest in Somme Nature Preserve and my daughter the endangered white fringed prairie orchid in Somme Prairie Grove. Over the past eight years, we have joined hundreds of others in the Forest Preserves around Northbrook cutting buckthorn, planting native seed and helping to care for this natural treasure in our own community.
There is one special place, however, which requires recognition. It represents to me both the treasures of our forest preserves and the insidious danger facing them. It is a little patch of oak savanna remnant nestled between two wetlands in Somme Woods. During the 1980’s and early 90’s it was one of the scattered patches of forest preserve restored to health through prescribed burns. Volunteers joined with Forest Preserve personnel to burn away the invasive Buckthorn which killed off the native plants. Other good people planted native seed to restore the Violet Cress, Zigzag Goldenrod, Cardinal Flower, and dozens of other native plants now found in the rare oak savanna ecosystem. The prescribed burns were part of a comprehensive program of ecosystem management that was begun on the North Branch in 1977 and carried out by Forest Preserve employees and volunteers for over twenty years. In 1996, a columnist in the Chicago Sun-Times launched a series of sensational attacks on the District’s restoration program, taking issue with all activities from prescribed burning to brush control to even the pulling of invasive weeds. President John Stroger was vilified in a Sun-Times cartoon that suggested he was clear cutting the forests to replace them by prairies. His response was to impose a moratorium on all management activities, from weed pulling to garbage clean-ups, including prescribed burns. For months the District held public hearings and listened to the counsel of experts before resuming its land stewardship efforts. In the years since then the District has been slowly rebuilding its staff and volunteer efforts. The areas of Northbrook preserves that had been recovering began to slip downhill. The grove of bur oaks in Somme Woods where the Red Headed Woodpecker once nested and the Virginia Wild Rye once grew became a tangle of Buckthorn shoots.
We are again in danger of losing a natural heritage unique to this part of the country and which has been highlighted in the New York Times science writer William Stephens’ Miracle Under the Oaks: The Revival of Nature in America. That fine book is largely about the Somme Preserves and the recovery under way. That little patch of savanna in Somme Woods is representative of what we stand to lose, if prescribed burns aren’t effectively reintroduced to Somme Woods before it’s too late.
NOTE: Prescribed fire has been safely employed in Northbrook for over twenty years, not only in the forest preserves, but also at Glenbrook North High School Prairie, the Chicago Botanic Garden, and Northbrook Park District sites. In 1999, the Forest Preserve staff once again began prescribed burns at Somme Prairie Grove and Somme Prairie Nature Preserve. But Somme Woods badly needs burns too.
The Rev. Jay Risk, in addition to volunteering with the Friends, is Rector of St. Giles Episcopal Church.
Today, where buckthorn once reigned, rich prairie and oak savanna vegetation has recovered.
From Earth Day to Solstice
By Donna Hochberg
The Friends have sought to make our forest preserves more a part of the culture of Northbrook. We sponsor events that range from fun to educational to hard work, often all three, including clean-ups, restoration work parties, tours co-sponsored by the Northbrook Park District, and family/children's events. We also assist with ecological tours of Northbrook forest preserves organized by the Field Museum, Chicago Botanic Garden, Morton Arboretum, National Audubon Society and others.
Our two popular annual events are the Winter Solstice Bonfire and the Earth Day Salamander Fest. The Winter Solstice celebration occurs at a spiritual time of the year when people think about the past and future. We encourage people at the bonfire to pick up a twig, chose a regret, a happy memory, or a hope, and toss the twig into the bonfire to see a bit of past or future flare up (some people feel that they could fell a whole tree). Along with the mesmerizing bonfire, the event may feature a bagpiper leading our procession through the woods to the brush pile, a falconer, singing, a recorder player who could have passed for the Pied Piper, as well as home-made cookies, warm cider, and hot chocolate.
The Salamander Fest at the Earth Day Celebration is always a big hit, especially with the children. We have our local blue-spotted salamanders on display, (kids can have their hands moistened and briefly hold their little slimy friends, an adventure that is irresistible to some), and some years we have an art table where kids create their own creative salamanders with various fun materials.
The Friends advocate conservation education and awareness, and we promote our goals through fun and interesting events. Come out and join us!!
Donna Hochberg, in addition to volunteering with the Friends, is a lawyer and Northbrook resident
New Trail
The “trail system” at Somme Prairie Grove in the past was simply the trampled paths that began wherever deer or people had walked, often following vehicle wheel ruts, gaps between thorn bushes, and intermittent watercourses. Some trails became deep mud whenever it rained for a while. So people would walk along the edge of the prairie vegetation, until that vegetation too was destroyed, and then walk a little further into the prairie until a wide mud patch developed. In other places, on slopes, some of the trails turned into erosion ditches more than a foot deep.
In August 2000, our first intentional footpath was installed, the initial work being done by scouts of Troop 64, as the Eagle Scout project of Andrew Smith. This “Indian file” foot path was designed by Friends members in consultation with FPD staff and soil scientists from the US Soil Conservation Service. Out in the open grassland, it is just a single footpath created mostly by people walking on it, with overhanging vegetation trimmed when the prairie grasses grow high. Here the key element is the avoidance of erosion by assuring that no long drainages develop. Essentially the footpath follows contours, rather than going directly up or down slopes except for short distances.
Stream crossings consist of “corduroy bridges” of black locust logs laid side by side. Some areas of soft soils were reinforced by limestone gravel, left over from the Deep Tunnel operation, a commodity of which the FPD has vast amounts. Probably the hardest work of the trail crew was cutting a way through dense buckthorn tangles. In some cases it was necessary to pass through these to avoid too much up or down hill. It also seemed like a good idea to have the trail pass through a few areas of buckthorn so people could see what this preserve once looked like – an utter ecological desert under the worst infestations.
An unusual feature of the new trail is the planting of a little plant called “path rush” throughout. This six-inch grass-like plant grows only in trampled trails. It simply is designed to take punishment and can compete nowhere else. This rush holds the soil and makes a great surface for walking. We hope to see it appear on the new trail in summer of 2001, but it may take a while. So far as we can determine, this rush has not intentionally been planted before in trail construction, although it pops up naturally to some trails in time.
In the spring of 2001 we will fortify some of the soggy parts of the footpath with crushed limestone (that the FPD has from Deep Tunnel excavation).
River Clean-Up
by Scott Ingersoll
The Friends have adopted the Middle Fork of the North Branch of the Chicago River
which runs through forest preserves between the I-94 Tollway spur and Sunset Ridge Road to the south. Each year on the Annual River Rescue Day of the Friends of the Chicago River we give a section of the Middle Fork its spring cleaning.
Over the past three years, we have collected approximately sixty bags of trash, bottles, car tires, old water tanks, lawn furniture, building materials, and oil barrels. Some of it we load into canoes and float it down to a bridge where it can be picked up.
Mike Piscal, a Friends leader and science teacher at Glenbrook North High School, enlists students to help clean the West Fork of the North Branch. The West Fork is the river that runs through downtown Northbrook and passes through Meadowhill Park.
The work is challenging at times, but we enjoy the camaraderie and the satisfaction of cleaning up our local waterway. While it is not glamorous work, it is great exercise, fun, and quite fulfilling.
Scott Ingersoll, in addition to his volunteer work with the Friends, leads canoe trips with the Chicagoland Canoe Base and is a lineman crew leader with Commonwealth Edison.
New Leadership Staff at FPD
The Northbrook Friends joined the Friends of the Forest Preserves and many others in appealing to Forest Preserve President John Stroger to ask for help at the top. There was no forest preserve Land Manager, no Volunteer Coordinator, no Superintendent of Conservation. In fact all three posts had been vacant for months. Some of the District’s best staff had retired or left the District, in part due to poor morale over disarray in the District’s land stewardship program.
We’re happy to report that the District now has excellent new leadership in those positions.
Steve Bylina is now General Superintendent, and he has been very responsive to Forest Preserve needs as advocates have presented them.
The new Superintendent of Conservation is Chris Merenowicz, a hard worker, problem solver, practical, effective, formerly the District’s fisheries biologist.
Volunteer Coordinator is Bill Koenig. Highly respected in his previous position as a conservation advocate with Friends of the River. Good leadership and people skills.
A Ferocious Wind
Fire, flood, windstorm, hail, plague, drought – ferocious events are a regular part of nature. The Northbrook preserves recently experienced a major blast. A major windstorm (called a microburst by some) ripped up hundreds of large trees by their roots or snapped them off like matchsticks.
Was that bad for the preserves? Or good? “It was some of both,” according to FPD ecologist John Elliott. “We hate to lose those old trees. Some of them are among that last of that generation that lived with bison and Potawatemi before Europeans ever settled here.” Elliott, who directs the River Trail Nature Center on Milwaukee Road, points out that some of the old oaks that were lost were more than 250 years old. “But clearing the way for young oaks is also a part of nature,” Elliott continued. “The preserves will be fine.”
Citizen Science
By Rickie White
More than twenty varied ecological studies are underway in Northbrook Forest Preserves. These studies are gradually giving us more knowledge, but we still perceive only a meager glimmer of what’s there. Ecologist Frank Egler once wisely said, “Ecosystems are more complicated than we think. And more complicated than we can think.” Yet we have to understand them as well as we can to make the best decisions for their care.
Recent and ongoing studies designed to inform land management decisions include:
· The impact of invasive species and of restoration on water chemistry and hydrology in Somme Woods by DePaul University, Steve McChesney of the Wetlands Initiative, and volunteers with the Habitat Project.
· The soils and vegetation of Chipilly Woods by Christiane Rey for her Masters degree at Northeastern Illinois University.
· Calling Frog Survey listening points at Somme Woods by Habitat Project volunteer Bill Leja. He found western chorus frogs, spring peepers, leopard frogs, and American toads – by listening to their calls.
· Relationships between frog populations and buckthorn and various other environmental parameters by Joe Walsh from Northwestern University
· The status of endangered plant species of Chipilly Woods and the Somme preserves by Susanne Masi of the Chicago Botanic Garden’s Plants of Concern and many Habitat Project volunteers.
· Annual census of endangered plant populations (prairie white-fringed orchid, small white ladyslipper, eared gerardia, American sloughgrass, savanna blazing star, and oval milkweed) by volunteers Linda Masters and Stephen Packard. (Locations of endangered species are kept confidential, for their protection.)
· Deer populations in Somme and many other forest preserves by Chris Anchor of the Forest Preserve District.
· Breeding birds of Somme Prairie Grove by volunteer (and later FPD assistant Land Manager) Jerry Sullivan and high-school volunteer Ben Risk (now studying at Dartmouth College).
· Breeding birds of Somme Woods by Jeff Sanders of the Evanston North Shore Bird Club and the Bird Conservation Network (spoiler: he found few birds in the dense buckthorn that covers most of the site).
· Butterflies of Somme Prairie Grove by Joan Palincsar and Jeff Sanders; butterflies of Chipilly Woods by Phyllis Adams – both working as volunteers with the Butterfly Monitoring Network.
We’ve certainly learned enough to say with certainty that restoration management improves the habitat for hundreds of species in our prairies and oak woodlands. Over 95% of the acreage of Northbrook’s forest preserves are currently left without management. More studies and more management are very much needed. If you’re interested in learning how you might take part, contact the Habitat Project hotline at 965-9239.
Rickie White is Science Coordinator for National Audubon Society of the Chicago Region
New apprentice stewards
Four apprentice volunteer stewards have been accepted by the FPD. They are Krista Clark at Somme Prairie, Dennis Dreher at Somme Prairie Grove, and Linda Masters and Jay Risk at Somme Woods.
Both apprentice and co-steward positions are available. Apprentices learn all aspects of land management. The learning comes mostly through helping with the many projects that occur throughout the year. The stewards and all the volunteers are crucial to the health of our preserves, and we owe them a wonderful debt of gratitude. (On the other hand, the stewards are quick to say that this work is some of the most rewarding they’ve done. It can be fun; it can be hard; but it’s all rewarding.) Contact the Friends for more information on positions available.
Feeling Good About Anetsberger
By Michael Beeftink
It felt especially good to be in our community last year, when voters overwhelmingly approved a referendum for the Park District to acquire the last large open land in central Northbrook. In March of 2000 the citizens of the Village voted in favor of a $15.5 million bond issue to purchase the 60-plus-acre Anetsberger property; the referendum passed by a margin of over 70%. The Friends of Northbrook Forest Preserves did our part to help. The Friends Newsletter discussed the merits of this property; members spoke at Village meetings and worked at getting signs of support on as many lawns as possible.
The benefits of maintaining this area as a multi-use open space are many. The property contains a nine-hole golf course and driving range open to the public. A section of the West Fork of the North Branch of the Chicago River runs through it. Plans call for restoration of wetland and grassland habitat for plants and animals and for paths for public use. The area also contains a small pond that for many years has been used for study by local ecology classes.
In October 2000 the State of Illinois awarded a $2 million grant to the Northbrook Park District from the state’s Open Lands fund. The grant commits the Park District to restore and preserve at least 14 acres as natural habitat. The Friends look forward to the potential of this land with its planned restoration and pathway projects as a valuable piece of natural environment for recreation, nature, and aesthetics.
Michael Beeftink is a Northbrook Resident who, in addition to volunteering with the Friends, teaches at Niles North High School.
Glenbrook North Prairie
By Rob Sulski
Few people know that one of Illinois’s finest prairies survives on the northwest corner of the Glenbrook North High School campus. Glenbrook North Prairie, a formally dedicated Illinois Nature Preserve, joins Somme Prairie Nature Preserve as our two gems of original prairie. (There are few other towns in Illinois that have even one top quality prairie within their limits.)
At Somme, the Nature Preserve is seventy acres. At Glenbrook it’s only two acres. But there’s another way to compare them. Somme has 2 acres of very high-quality prairie. Glenbrook has about one acre. Not a bad second.
Glenbrook harbors near saturation numbers of very rare natives such as Prairie Gentian, Cream Wild Indigo, Prairie Cinquefoil, Alum Root, Lead Plant, Sky Blue Aster, Hoary Puccoon, Violet Wood Sorrel and Prairie Dropseed Grass. It’s an irreplaceable piece of the rich ancient ecosystem that the buffalo walked on for thousands of years.
Rob Sulski, as a boy, played in Northbrook Forest Preserves. Perhaps as a result, in addition to his volunteer work with the Friends, Rob is a scientist with the Illinois Environmental Protection Agency.
Thanks to Rich DiLillo…
…for twice repairing broken rails and posts in the split rail fence at the entrance to Somme Prairie Grove. Mr. DiLillo is superintendent of the Skokie Division of the forest preserves. The fence materials had been donated by the Northbrook Civic Foundation to stop a long-term problem of preserve trashing by vehicles, garbage dumping, joy riding. Rutting and soil compaction by vehicle wheels was seriously damaging this delicate ecological preserve. One section of fence had been broken by a trespassing vehicle.
Thanks to Andy Smith…
… for his work to lay out and install the new Somme Prairie Grove footpath as his Eagle Scout project. Thanks too to all the scouts of Troop 64 of Northbrook United Methodist Church. Future tours of the site – frequently sponsored by the Field Museum, Chicago Botanic Garden, Morton Arboretum, Nature Conservancy, Audubon and others – will all use Andy’s trail.
Thanks to Tom Tokarz…
… for the wood chips used by the Troop 64 scouts to mark and improve the new Somme Prairie Grove trail in wooded areas. Tom also is the one who chain-saws trees that fall across trails and fire breaks.
Bittersweet Evening
By Stephen Packard
I felt a bit like a nervous parent. I had gotten a call alerting me that Somme Prairie was scheduled to be burned around mid-day, if all went well, on April 13, 2000. I wasn’t free to help that day, but I was hopeful that this preserve, suffering badly from too little burning in recent years, might be perking up. As soon as I got a chance, just before dusk that evening, I took a bike ride over to see if the prairie had been burned, if the job had been a good one, if errant vehicles had rutted up the delicate turf, if the fire had been hot enough to be effective. The first answer was – no. No burn. For whatever reason, it hadn’t happened. But what a magical place to take an evening walk. Deer grazed within a dozen yards of where I entered the prairie. A meadowlark was singing his last songs of the evening in the dying light. The shoots of the very earliest prairie plants were emerging. Oooops, emerging and being eaten. Many rare stems had been eaten down to ground level. Deer are beautiful animals, very much a part of our prairies and savannas. But it’s possible to have too much of a good thing. In the absence of predators, too many deer are a close second to lack of fire as a threat to the survival of the animals and plants of the prairie. In the middle of the largest opening I stopped to count them. Seventeen deer visible at once in one opening. Experts estimate that a healthy population for our ecosystems is somewhere between 7 to 15 deer per square mile (640 acres). Seventeen deer in twenty acres is vastly too many, as we’ve long known. Many of the plants survive there now only in deer-exclusion cages; if the numbers of deer can’t be reduced in time for these species to reproduce, they’re doomed.
Then I notice two spry little deer I hadn’t seen before. Oooops again. They’re coyotes, just appearing from their den. Beautiful animals, unusually tame in the thickening dusk. With a look at me over their shoulders, they trot off. The air smells sweet. Such are the joys and agonies of being a parent to rare ecosystems.
Stephen Packard, in addition to his volunteer work with the Friends, directs the National Audubon Society of the Chicago Region.
FLORA AND FAUNA
The charter of the Forest Preserve District of Cook County commits it to maintaining its lands “…for the purpose of protecting and preserving the flora, fauna and scenic beauties within such district, and to restore, restock, protect, and preserve the natural forests and said lands together with their flora and fauna, as nearly as may be, in their natural state and condition, for the purpose of the education, pleasure, and recreation of the public.” In this section we try to summarize what is known about the flora and fauna, and of nature generally, within the Northbrook forest preserves.
The Trees in Our Forest
The Friends have identified more than forty species of native trees living in the Northbrook forest preserves. On river flood plains, we found silver maple, green ash, American elm, cottonwood and various willows are common. In open savannas, the major trees are bur and scarlet oak. The open oak woodland was our predominant forest type, during the thousands of years that our forests have evolved here, since the last glacier. Thus, oak woods are especially rich in the wildlife that depends on our forest preserves. Here many kinds of oaks and hickories predominate, often bur and white oak mix with shagbark and bitternut hickory and black walnut. The understory trees include hazelnut, Iowa crab apple, and American plum. Denser woodlands were less common in Northbrook in the past; but then as now the major trees were red oak, sugar maple, and basswood in the canopy with hop hornbeam and witch hazel in the understory.
Invasive trees are one of the major threats to our oak savannas and oak forests. Many people know that European buckthorn and certain other alien trees are major threats. But most don’t realize trees native to this region can also get out of balance in ways that reduce biodiversity. A smothering invasion of ash and box elder from the floodplain can turn an open oak woodland into the unstable and degraded community shown on Forest Preserve District planning maps as “Unassociated Woody Growth”. Sugar maple and basswood, beautiful and typical trees of ravine forests or slopes on the east sides of rivers, often join the buckthorn as the major problem invaders in the oak hickory uplands. An oak woods degraded by invasives first loses its characteristic birds, butterflies, and certain species of wildflowers. An oak woods that has no oaks in the understory is a tragic ecosystem. Well-planned restoration can bring that community back to good health. The Friends each summer host a series of tours in partnership with the Northbrook Park District to show off some of great forests of Northbrook and highlight what restoration is (and is not yet) accomplishing.
Prairie Restoration (or is it savanna?)
Only about two acres of Somme Prairie Nature Preserve (the seventy-acre forest preserve area behind the Northbrook Post Office) survived as Grade A prairie through the mid seventies, according to the Illinois Natural Areas Inventory. And even that pittance was badly invaded by brush when forest preserve volunteers started managing it in 1978. The buckthorn has been gradually on the retreat over the last two decades, and seed collection and broadcast have expanded the higher quality areas.
The “prairie openings” in the 85-acre Somme Prairie Grove are also impressive examples of restoration. Here about twenty acres of old fields, which twenty years ago had only a few prairie species surviving in most parts, has been nurtured into a colorful kaleidoscope of rare flowers, grasses, butterflies, birds, and more.
But was this ever prairie? Although people commonly refer to these openings as “prairies,” and many species are typical of prairies, a careful ecologist might be more likely to call them savanna openings. That distinction will become more obvious as the site’s numerous young oak trees mature. Unlike Somme Prairie to the west, this area has savanna soils, and the 1839 Public Land Survey shows scattered trees here, unlike the treeless prairie on the dark prairie soils west of the river. Many of the original trees of the opener areas were probably cut for wood when parts of this area were farmed. All savannas have many prairie species present, but the prevalence of certain indicator plants and animals (cream gentian, blue-winged warbler, Edwards hairstreak, hazelnut, for example) alert us that, aside from the oak woodland groves, the site is largely savanna. Some people are disappointed to learn that these areas aren’t prairies and never will be. But a healthy savanna is even rarer than the prairie, so let’s be thrilled with what we’ve got.
Botany Bliss
By Linda Masters
Two rare and wonderful plants came into their own at Somme Prairie Grove in 2000. The ecological restoration that has been going on there for over a decade is known for its innovative techniques and its quality, and each year more richness emerges.
This year the surprises were - white prairie clover and pale Indian plantain – two species characteristic of high quality prairie and oak savanna respectively. White prairie clover is perhaps the most "conservative" of the prairie legumes, a group that includes the bush clovers, tick-trefoils, leadplant, false indigos, and milk vetches. "Conservative" plants are the ones that just can't handle disruption. They are the first to be lost when a natural prairie, woods or wetland is degraded – and the slowest to return when healthful conditions are restored.
As long as ten years ago, one plant of white prairie clover appeared at Somme in the large grassland opening just northwest of Vestal Grove. But this plant didn't seem to want to reproduce. It just sat there. Some years it was eaten down by the deer, some years not. But restoration crews continued to gather small amounts of white prairie clover seed from a few nearby sites, grow plants in seed production gardens, and distribute the resulting seed in the best quality prairie areas along the North Branch, including Somme Prairie Grove.
White prairie clover is slow to establish and grows slowly as well. But in 2000, it finally came through; plants are growing in at least five different areas. In time it may well join the similar purple prairie clover as one of the major herbs of our rebounding prairies.
Pale Indian plantain was a common plant of the region according to some of the older texts. But as its savanna habitat was lost, it disappeared. When the restoration volunteers searched the landscape for seed sources, the closest site for pale Indian plantain was in northern McHenry County. Plants from this source grew in back-yard seed-production gardens, and eventually tens of thousands of these seeds found their way into the restoration mixes. Even so, for years, only a plant or two of this species showed up at Somme Prairie Grove. In 1999 a few more were evident, but in 2000, pale Indian plantain showed up in impressive numbers, widely scattered over the site. It appears that another nearly lost plant has found a secure home once more.
Linda Masters, in addition to her volunteer work with the Friends, is former director of Conservation Research Institute. She currently works with the Corporation for Open Lands (Corlands).
 |
| Puccoon, phlox, and golden Alexanders backed up by those big prairie dock leaves |
Frogs, snakes and salamanders
Northbrook Forest Preserves are currently known to be home to four frog species, five snake species, and one species of salamander, the blue spotted.
The frogs are being monitored by volunteers of the Chicago Wilderness Calling Frog Survey. Frogs are important indicators of water and habitat quality. The four species are the western chorus frog, spring peeper, leopard frog and American toad.
Snakes seen in Northbrook Forest Preserves include the smooth green snake, plains garter snake, Chicago garter snake, midland brown snake, and the red-bellied snake. Others that are possible but have not been confirmed in recent years include the Kirtland’s snake, massassagua rattler, and fox snake. If anyone sees or knows of any other species of frog, salamander, or snake in Northbrook forest preserves, please let us know.
Breeding Birds
According to the Chicago Region Biodiversity Council, the most significant breeding birds of the region are the grassland and shrubland birds, followed by those of open oak savanna and woodland, and those of wetlands. Typical grassland species need at least fifty acres of grasslands to reproduce successfully. None breed here now. The only likely place for them for them to return would be Somme Prairie, if more trees and brush were cleared. The master plan there calls for the prairie to be expanded to about seventy acres through cutting back the encroaching brush. But currently the largest patch of open grassland is only about twenty acres, and the ongoing prescribed burning and brush-cutting work has only gained about an acre per year. Fire and saws and loppers eat away at some edges of brush patches each year, but others that are not burned or cut grows bigger. In fact, due to a less effective burning program recently, some years have a net loss of an acre or two.
Shrubland, savanna and open woodland birds have about sixty acres of good habitat at Somme Prairie Grove. Breeding birds there include blue-winged warbler, yellow warbler, chestnut-sided warbler, blue-gray gnatcatcher, crested flycatcher, and field sparrow.
A significant raptor which breeds at one or another of the Somme preserves each year is the Cooper’s hawk. The red-tailed hawk breeds each year at Somme Prairie Grove, and the great horned owl often takes the previous year’s red-tail nest when it lays its eggs, amazingly, each February. Great horned owls have also been found breeding in Chipilly Woods and the Anetsberger property.
Butterflies and Brush
By Joan Palincsar
Two Northbrook forest preserves are very rich in the rare butterflies of grasslands and open woodlands. Somme Prairie has at least 14 species, and Somme Prairie Grove has 35. There are 14 types of skippers, a fact that is very encouraging because it means that the site maintains the necessary habitat conditions and food plants for each. Other butterflies demonstrating this diversity include the silvery checkerspot, banded hairstreak, and Appalachian brown. Most conspicuous to the casual visitor in summer are dozens of dark brown wood nymphs bouncing up and down in the meadow grasses, and great spangled fritillaries sailing above the flowers. Tiger swallowtails, monarchs and sulphurs are also easily seen. There are many different dragonflies at Somme, which Jeff Sanders and I are working on listing for the future. The site needs to be burned. Shrubs are rapidly growing taller and wider. The butterflies need the occasional burning that maintains the great diversity of food and nectar plants.
Joan Palincsar, in addition to her “citizen science” efforts at Somme Prairie Grove, is volunteer steward at Ryerson Woods in Lake County.
THE PRESERVES
Chipilly Woods
Rich oak forest on the uplands with floodplain forest along the ditched Middle Fork of the North Branch of the Chicago River. Popular for hiking and cross country skiing. Park where Grant road makes a right angle. In many parts, buckthorn and garlic mustard are still sparse. Needs prescribed burns and control of invasive species. Some of the species of open woods (i.e. two-flowered cynthia and New Jersey tea) and rapidly fading out due to increasing shade from invasives. Recent ecological study by Christiane Rey of Northeastern Illinois University. Bird monitoring by Margo Milde.
Two recent unfortunate, uncontrolled fires in Chipilly Woods may have been set by kids. There is a “camp” on the western (upwind) edge of the burn area. The Northbrook Fire Department put out the Chipilly fires in both years. One fireman was injured in the spring of 2000. More coordination with the Forest Preserve District is needed. At some preserves, according to approved plans, low-level ground fires are allowed to consume the available fuel in selected areas under the control of Forest Preserve staff and volunteers.
Chipilly is a fine woods that is deteriorating. It very much deserves a stewardship program. Garlic mustard is just getting started in the better parts; a pulling crew that worked each June for a few years could control it. Buckthorn is nearly absent in some parts; it would not be too much work to keep it that way. A fire plan could be written that would alleviate the necessity of the Northbrook Fire Department to intervene. Since fuel levels are light and fire breaks readily available, it would only take one FPD staff person and a few trained volunteers to control a fire and let it burn out.
This kids camp is another problem, a minor one so far as the health of the preserve is concerned. But the immediate “camp” area is a mess of cans and bottles, tree-house construction, and other classic kid stuff. Kids will be kids. We’re glad they use the woods and don’t mind cleaning up after them a bit from time to time. Anyone have ideas for engaging the kids in these woods in a more positive way?
But the real threats are the buckthorn, garlic mustard, over-populated deer, and the need for controlled burns.
Des Plaines Preserves (Potawatomi Woods and Dam # 1 Woods)
The parking lots and mowed areas are heavily used by picnickers. There are large areas of bur, white and red oak woodland along with maple-basswood forest, former wet savanna, floodplain forest, and other communities. These areas were extremely rich until recent decades when populations of white-tailed deer exploded; in that regard the DesPlaines preserves are said to be the most damaged area in the Cook County Forest Preserves. Many plant and bird species for which the areas was known are now gone, possibly for good. The Friends are not aware of any monitoring in progress.
Mary Mix McDonald Woods
This is the northeastern part of the Forest Preserve area managed by the Chicago Botanic Garden. It represents one of the largest, finest, and most studied oak woodland restorations in the midwest. Unfortunately it has not been burned in recent years, apparently because of bureaucratic red tape. Although the garden staff is capable of doing the work on their own, the necessary authority has not been granted. Thus the woods, though recovering nicely until a few years ago, are once again degrading. But it’s still a fine woods, and illustrated signage along an interpretive trail provides a good introduction to the restoration ecology of the oak woods.
Skokie Lagoons
Popular for birdwatching, fishing, picnics. There’s almost none of the original natural ecosystem here, since the ancient natural marshland was reshaped into ponds and mounds. The uplands are covered almost entirely by invasive tree species with an understory of garlic mustard. In recent years the Chicago Audubon Society has planted tens of thousands of marsh plants under the direction of FPD staff and volunteer steward Jerry Garden.
Somme Prairie Grove
About 85 acres of oak woodland and savanna. The FPD has approved a restoration plan, with most of the work carried out by volunteers. See also “Botany Bliss,” “Breeding Birds,” “Prairie Restoration” and “Butterflies and Brush.” The volunteer site steward is Steve Packard. Apprentice stewards are Stuart Goldman and Dennis Dreher.
Somme Prairie Nature Preserve
70 acres of Forest Preserve with added protection as a dedicated Illinois Nature Preserve. About twenty acres are in prairie openings. The rest is covered by dense invasive brush. Parts of the original channel of the West Fork of the North Branch of the Chicago River are evident after heavy rains. See also “Butterflies and Brush,” “Prairie Restoration,” and “Bittersweet Evening.” The FPD has approved a restoration plan, with most of the work carried out by volunteers. Volunteer steward is Laurel Ross. Apprentice stewards, Christiane Rey and Krista Clark.
Somme Woods
About 250 acres, mostly oak woodland. Includes some former prairie and savanna on the west and north edges, and floodplain thickets to the east. The FPD has approved a restoration plan, with most of the work carried out by volunteers. Apprentice stewards, Linda Masters and Jay Risk.
Sunset Ridge Woods
Parts of the original channel of the Middle Fork of the North Branch of the Chicago River are evident; the surrounding floodplain forest has ancient swamp white and bur oaks, and traces of the understory remain. Rich oak woodland survives on the narrow upland west of the river. Some savanna has been maintained brush-free by mowing, apparently by a neighbor. The Friends are not aware of any monitoring or stewardship, aside from the annual river clean-up.
References
If you’d like to learn more about the ecology of the Northbrook forest preserves, there are plenty of opportunities.
The best “primer” is the Chicago Wilderness Biodiversity Atlas.
For a fine summary of conservation options for this region, see Saving Nature in Your Community edited by Dennis Dreher and Jason Navota. Published by the Northeastern Illinois Planning Commission.
A good overall introduction to the prairie is Where the Sky Began by John Madson (Houghton Mifflin).
Northbrook forest preserves are featured in Miracle Under the Oaks by New York Times science writer William K. Stevens (Pocket Books). As a special bonus, it contains descriptions and maps of the restoration at Somme Prairie Grove forest preserves. This book covers the early decades of the new discipline of ecological restoration, with the restoration of preserves along the North Branch as a focus.
For a technical introduction to restoration, consult the Tallgrass Restoration Handbook: for prairies, savannas and woodlands, edited by Stephen Packard and Cornelia Mutel (Island Press).
An overall summary of the conservation priorities of the Chicago region (including a description of the region’s ecosystems) can be found in the Biodiversity Recovery Plan of the Chicago Region Biodiversity Council at www.chiwild.orgThe conservation of oak woodlands and savannas is summarized in the Oak Ecosystems Recovery Plan, available from the U.S.Environmental Protection Agency available on the web at: http://www.epa.gov/grtlakes/oak/oak95/call.htm
Other good materials on the web include Endangered Ecosystems of the United
States at http://biology.usgs.gov/pubs/ecosys.htm and the Report of the
Status of and Restoration Efforts in Oak-Dopminated Communities in DuPage
County at http://dupageforest.com/EDUCATION/oak_research.html
The Fourth Year Report was assembled by us Friends volunteers including Linda Masters, Jay Risk, Stephen Packard, and Donna Hochberg with generous editing support by Northbrook village trustee (and later Village President) Sandy Frum.
