The other day I spotted a spiderwort (Tradescantia ohiensis) in bloom. Not many native flowers bloom this late into the season, so it caught my eye. Of course, this has been an exceptionally warm autumn, so it didn’t surprise me altogether to see the bright blue denizen of the summer prairie basking in the bold October sunshine. But I’m used to seeing it flower in June and July, so I consulted a couple of reference texts. The online resource, “Illinois Wildflowers,” suggests that the bloom time is from late spring to midsummer; likewise, the Ohio Prairie Association reports that it flowers from “late May to early July.” However, Flora of the Chicago Region by Gerould Wilhelm and Laura Rericha cites bloom dates observed by the authors ranging from May 14 to October 27, so my own observation was hardly unprecedented.
Thankfully, interested witnesses have been recording such information for much of our history. Phenology is the name we apply to the timing of events in nature and people have been recording such data for thousands of years. According to Project BudBurst, “The Chinese are thought to have kept the first written records of phenological observations dating back to around 974 B.C.” While records here in the Midwest are nowhere near that old, we do have some pretty good local data from the past hundred years or so.
Famed conservationist Aldo Leopold collected phenological data in Sauk County, Wisconsin from 1936 to 1948 and his daughter, Nina, resumed the tradition from 1976 to 2011. In his seminal work, A Sand County Almanac, Leopold shared, “Keeping records enhances the pleasure of the search and the chance of finding order and meaning in these events.”
Leopold was in good company. Back in Massachusetts, Henry David Thoreau recorded his observations of nature in a daily journal spanning the years of 1851 through 1858. Included in his journals are the first flowering dates of hundreds of local forb species.
If, like me, you enjoy making such observations (bloom dates, seed ripening, etc.), you might like to volunteer to assist with the collection of phenological data for the Forest Preserves of Winnebago County. If you’re at all curious, I invite you to save the date, Saturday, February 3, 2018, for a Species Spotlight orientation and training for plant monitoring in the year ahead—including a proposed phenology project. There are several other monitoring projects planned under our Citizen Science program; join us January 20 for a Citizen Science Spotlight to learn more. Further details are forthcoming so keep an eye on our online calendar.