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Plant Paleoart Through the Ages by David Bressan, Scientific American Blogs, November 23, 2012 http://blogs.scienti...rough-the-ages/ http://blogs.scientificamerican.com/history-of-geology/ Best wishes, Paul H.

On our 4th visit to St. Clair, we set a goal to find some of those iconic "scale trees" we keep reading about - the now extinct lycopsid trees with the pock-marked "scaled" trunk and roots. The bark is pock marked with scars left by the leaf stalks and rootlets when they fall off. Did we find Scale Trees? Boy, did we ever! In addition to the samples we collected, Nancy and I found some incredibly cool samples embedded in large boulders, on the floor of the quarry, even on the trail - these are either fragile or positioned on boulders so they can't be extracted without shattering them, so they are there for any visitors to photograph and enjoy! We have had wildlife encounters on every visit - a 6 to 8 foot long black snake coiled near a water pool on the trail, fresh black bear tracks on the trail and scat (and a sighting by MZKLEEN the same day we were there), and on this trip a very large spider on the trail (see image). Fossils On Boulders! - The first "embedded" scale tree fossil (Stigmaria - root with rootlets clearly visible) was located on top of a huge boulder - Nancy discovered it and excitedly called me over to see it. It was bright yellow and very well defined as you can see from the picture. I had to climb on other boulders to reach this one, and took a photo with my rock hammer to show the size and scale (Image 1). It was extremely well preserved but it is exposed to the elements and the top of the boulder is very brittle so it is impossible to extract - if someone tries, it will almost certainly be destroyed. The second sample I discovered on a boulder at the other end of the quarry (Image 2 - you can see my boot on the boulder), and Nan discovered a third which I photographed to show the surrounding woods (Image 3). Finding these and just looking at them was thrilling, like touching history. We hope other collectors leave these as monuments for everyone to enjoy (and don't destroy them by trying to whack off some fragments). NEW QUESTION: Most of the fossil samples we see online show the scale tree bark with "leaf scars" but very seldom show the leaves attached. How do we know when the samples are roots and rootlets, or branches and leaves? Some of the Stigmaria we collected look like branches or small trunks with leaves but most people are telling me that these are all roots. Would appreciate clarification. What do the scale tree branches with leaves attached look like? We also saw extremely large trunks of Calamites and Lepidodendron beginning to show through the floor of the quarry near the boulders - this is very dramatic and as more shale wears away the erosion will reveal more of these really large trunks (this is up the slope directly above bottom area with all the large boulders, behind the large boulder covered with white crystals). It was really cool to find these white and golden yellow-tinged scale tree fossils in plain sight on large boulders - it really brought these trees to life, showing the leaf scars and rootlets that look like thorns spreading directly out from the trunk). Ironically, we didn't notice these scale trees on our first three visits - we did collect a few Calamites and Siggularia bark pieces then, but nothing special. Making Scale Trees (Lepidodendron) our TARGET forced us to focus on this and suddenly, we noticed that they were concentrated in certain areas that we never noticed before. Nancy found the last embedded scale tree (Stigmaria) fossil right on floor of the quarry trail - it was going to be destroyed by traffic so I checked it out and saw that it appeared to be loose and to my surprise, it popped out in two pieces - this is a cool piece because the pattern is white like most St. Clair ferns. The first photo (4a) shows the fossil embedded in the trail - it doesn't look like much and is actually hard to see (Nancy's keen eyes spotted it right away) - the second photo (4b) shows the recovered fossil. Collected Samples - We excavated some samples to bring home, and also found some nice samples that other collectors had discarded from fossil pits - you can see how interesting the patterns are. The roots with rootlets attached are not easy to find - as you can see, all of our samples have rootlets attached) - they make nice displays (Images 5, 6 and 7). The two fossils in Image 7 were revealed after segmenting a piece of shale. Annularia and Calamites - The last Image shows a single rock specimen that shows up in two different colors. It looks like two separate pieces but they are actually attached - the top part shows Annularia including a unique fossil that is a cross-section showing the stem in the center and the leaves radiating out like a star, and lots of smaller fronds. The bottom section shows pieces of the Calamites bark associated with Annularia. This makes for a nice display piece. We will display these fossils and also use them as illustrations for future articles and maybe a book - we also reinforced our strategy of setting specific goals for each trip, such as looking for a specific type of fossil species, or category, or even just agreeing to aim for a large size display fossil. This determines how we approach each site, where we explore, and even how we excavate. After 4 visits to St. Clair, we still find it to be new and exciting even as it gets more familiar on each trip - we're sure that you probably feel the same way about your favorite sites, especially if they are close to your home.

I can't seem to find an image or plate for this in my fossil books - this is a long branching vine or stem with elongated veinless leaves running along the stems. I've included a full view as well as closeups showing the leaves. The leaves are flat and long and run along the stem in a series. My impression is that this is a small vine of some sort with leaves running along the stems. It is one of our finds from the Llewellyn Formation at St. Clair. Any ideas? Image P8302029a includes arrows pointing to the leaves running along the stems, at the base of the fossil. Image P8302016a shows the major branching stems - there are also minor stems Image P8302012a is a closeup of the leaf which appears to have no veins. Image P8302020a shows another leaf closeup. Image P8302013a and P8302017a show a closeup of a single leaf.