Chicago Region Tops U.S. National Parks in Native Plant Biodiversity!
Part 2
(Originally published on 1-17-2018 and updated on 1-14-2022)
A national-park quality blooming event happens every single day from mid-April through mid-September in the Chicago area. On this June morning, a celebration of life is unfolding. Endless blooms of sand coreopsis spread with golden joy along the banks of the Dead River at Illinois Beach Nature Preserve in Zion, Illinois.
Last week, in the first part of this series, I compared the natural splendor of the Chicago region to the sixty U.S. national parks. I framed the beauty and biodiversity of the Chicago in terms of the famed and revered national parks to help us better communicate the natural splendor of our region in a way that people instantly understand and respect. I used data from the book Flora of the Chicago Region (by Gerould Wilhelm and Laura Rericha), the NPS species database, and Wikipedia.
First, I found that the acreage of combined protected natural area within a narrow 50-mile radius of downtown Chicago ranks 25th—greater than 35 national parks, including Grand Teton, Rocky Mountain, Mount Rainier, Badlands, Zion, Bryce Canyon, Arches, and Acadia.
I also found that the Chicago region, defined by a 75-mile radius of downtown, ranks 1st in the number of native vascular plant species, totaling 1,867. That’s 323 more than the most prolific national park, Grand Canyon, which comes in with a total of 1,544. But what about a more reasonable 50-mile radius that matches the previous finding? In this second part, I look into this question and get the numbers straight so that it’ll be easier for you to spread the good word.
The authors of Flora of the Chicago Region used species and location data from a 75-mile radius of downtown Chicago, “This circumscription was based upon the idea that a field trip within the region can be reasonably be accomplished in a day.” That sounds reasonable. And it’s a lot more convenient and less costly than visiting any national park. But if you look at the book’s map, it includes unlikely places like Berrien County, Michigan. I can’t imagine any Chicago-area resident naming any Michigan location as part of the Chicago area. And I don’t think many Berrien County residents call their home “Chicago,” unless they were vacationing in Afghanistan and someone asked them where they lived. For me, I feel comfortable saying that Lake County, Indiana is part of the Chicago region. My logic is that it’s right across the Chicago border and a lot closer to downtown than Illinois counties like McHenry or Kankakee. Everyone has his own opinion. Therefore, I’ve broken down the data from the book to help any Chicagoan arrive at a species count based on his own personal definition of the Chicago region.
At this portion of Indiana Dunes National Lakeshore in Porter County, Indiana, wild lupine and hoary puccoon stage a gorgeous duo on the May dunes of this black oak savanna.
Back when Chicago Wilderness was young, they defined the original Chicago Wilderness region in their 1999 publication An Atlas of Biodiversity. It contained the “Original Six” northeastern-most Illinois counties of Cook, DuPage, Kane, Lake, McHenry, and Will, the northwest Indiana counties of Lake and Porter, and a small patch of Kenosha County, Wisconsin that I think only included Chiwaukee Prairie. This original Chicago Wilderness region is roughly contained within a 50-mile radius of downtown Chicago. Its border forms a choppy semicircle to the west and slightly south of Lake Michigan. Personally, I find this regional definition quite acceptable, and I don’t object to adding Kankakee, Kendall, and Grundy counties to the mix.
Currently, the only way to count the species for each county is to go through every page of Flora of the Chicago Region and record them by hand. After last week’s post, I did just that. I thought it would take at least a week to create a spreadsheet, but it only took twelve hours of painstaking monotony.
More than twice, I turned through the 1,135 species pages and evaluated the locator (dot) map for each of the 3,149 plant species. I excluded the non-native plants and parsed the native ones by county. Because the Chicago Wilderness’s Original Six Illinois counties make up the core of the region, I didn’t create individual counts for those counties. However, I did break down the counts for species that uniquely occurred inside the Illinois counties of Grundy, Kankakee, and Kendall, the Indiana counties of Lake and Porter, and the Wisconsin county of Kenosha. This way, like Mr. Potato Head, you can start with the Original Six and then attach the counties of your liking to come up with your own regional mishmashes and their associated species counts.
Regarding any error in the counts, I don’t think my counts are off by very much. I went through the data more than once and approached it from different directions. However, until an official database of this information is compiled, you can assume that it’s easily reliable enough for your messaging. Download the spreadsheet. If you dare, please feel free to check the results against the pages of Flora of the Chicago Region, make the appropriate corrections, and let me know.
Here are my results1 for the total number of vascular native plant species:
• Grand Canyon National Park: 1,544 (most of any national park)
• Indiana Dunes National Park: 1,196 (remarkably, all within just 15,000 acres)
• 11-County Region2: 1,756
• “Original Six” Chicago Wilderness Illinois Counties3: 1,608 (well within a 50-mile radius)
• Original Chicago Wilderness Region4: 1,706 (within a 50-mile radius)
• Outside the “Original Six” Illinois Counties3: 148
1 – Guestimated human error +/-3 species
2 – The 11 Counties. IL: Cook, DuPage, Kane, Lake, McHenry, Will, Kankakee, Kendall, and Grundy / IN: Lake and Porter
3 – The “Original Six” Illinois counties from Chicago Wilderness’s “An Atlas of Biodiversity” are Cook, DuPage, Kane, Lake, McHenry, and Will.
4 – Original Six2 Illinois counties plus Lake (IN), Porter (IN), and Kenosha County (WI)
In May, Pembroke Savanna in Kankakee County is home to a sublime floral display of white sand phlox and rare bird-foot violet.
Indiana Dunes National Park, located in Lake and Porter Counties of Indiana, is home to 1,196 species within just 15,000 acres. I wondered how the numbers would react if I left out those two Indiana counties, which was originally part of the original Chicago Wilderness region. It turns out that the Original Six Illinois counties are home to 1,608 native species, still more than any national park. Only 34 species from Lake County (IN) and 62 from Porter County do not reside in northeastern Illinois (the “Original Illinois Six” counties plus Kendall, Grundy, and Kankakee).
So what does all of this mean? The Chicago region ranks first in the number of native vascular plant species compared to any U.S. national park, with the Grand Canyon being the highest of the parks at 1,544. The total for just the Original Six Illinois counties is 1,608 species, and it only goes up from there. If you add in the Indiana counties of Lake and Porter, the total grows to 1,704. Throw in Kenosha County, Wisconsin to complete the Original Chicago Wilderness Region, and it’s 1,706. No matter how you slice it, Chicago ranks first. It is no coincidence that the first chapter of my book about Chicago nature bears the title “Second City, Second to None.”
—Mike
