Glacial relicts

One of the badges I wear as an outdoorswoman is that of Plants of Concern monitor for the Chicago Botanic Garden.  We do annual studies of rare plants in the region to determine whether populations are declining or in trouble.  I've been monitoring the Carex bromoides (brome hummock sedge) at Spicebush Woods for a few years, and agreed to start monitoring the Juniperus communis (the poorly named common juniper) at Harms Woods this year.  I only agreed to this because since it's a conifer, it could be monitored pretty much any time of the year, unlike C. bromoides, which is in flower right smack dab in the middle of one of my busiest times of year--May, the season of AP field trips and end-of-school-year madness.  I meant to get to it during my Summer of Nothing, but too much of the nothing got in the way.  So here we are, monitoring it on a chilly October day.  Despite the lovely sunshine, it was breezy and uncomfortable, as I was dealing a throbbing sinus infection and did not have the foresight to bring a pair of gloves with me.  Juniper is tangly and prickly, and it scratched the hell out of my hands until I found an old pair of dirty socks in the trunk of my car to wear as clumsy mittens.  The things I do for my friends in Kingdom Plantae...

Juniperus communis is a 10, according to Swink & Wilhelm.  It's a creeping juniper shrub that is normally found on dunes around Lake Michigan, and is rare because that habitat has pretty much been urbanized.  Harms Woods, for those in the know, is not a dune landscape near Lake Michigan.  It's a flatwoods along the North Branch of the Chicago River, quite a ways west of the lake.  So what in the dickens is this plant doing there?  The colony I monitor is on a sandy bluff (if you can call the low banks of the Chicago River "bluffs" without laughing) over the river, and is most likely a boreal relict from the days of the last glacial retreat.  It's hanging on in this unlikely spot along with some other rare pals from the olden days, now considered to be northern and/or dune specialties--Aster macrophyllus (big-leaved aster) and Maianthemum canadense (Canada mayflower).  For whatever reason, this spot has remained cool and shady enough to allow these fossils to hang in there.

 The tiny juniper colony.  Rebecca is counting stems, which is probably an exercise in futility.  I am 99% sure that it is all one ancient plant, connected underground.

 Up close, with its snazzy little pinstripes.  We midwesterners don't get a lot of conifers, so we find them fascinating.

 What is wrong with me?  I stupidly decided not to bring Swink into the field with me, because I figured I would know all the associate species.  Well, pride goeth before the fall. Damn you, closely-related viburnums!  This is V. recognitum or V. rafinesquianum (one of my top-five Latin names!)...it comes down to petiole length.  Does that petiole look shorter or longer than 1.2 cm?  I'm leaning towards longer, which would make it the non-native recognitum.  Bollocks.

 A horizontal Aster macrophyllus, leaning out from the riverbank.

The trail on the hike out.  Looks like a friggin' Thomas Kinkade painting!