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On our recent half day trip to the St. Clair fern pits (Aug 11), we focused mostly on finding fossil fern seeds. All of these seed fossils came from one half-day visit. The isolated fossils were found on pieces of shale we inspected from the many piles strewn around the excavated collecting pits. Those that show both halves came from fragmenting small to medium sized pieces from the cast-off pieces around the pits. This was a time-consuming exercise in patience and involved a certain amount of luck but as you can see, we accomplished our goal which was to collect some well-articulated seed fossils. Most of these are Alethopteris seeds including the best find (1a/1b) that shows both halves of the seed and the seed stem. We're wondering about the "split top" seeds - are these Alethopteris seeds starting to open up, or something else? At least two of these (Seeds 4 and 5) are shapes we can't find in the fossil reference literature. 1a and 1b. Alethopteris seed attached by stem. Our best find was this trigonocarpus (fern seed) showing the stem attached to an Alethopteris sprig. We haven't seen too many seed fossils this well defined including the seed stem and associated fern leaves all attached to the same stem. Update: "Trigonocarpus" is the general name given to fern seeds. Our seed is attached by a short stem to the mid-rib of an Alethopteris fern pinnule. We do not believe this is a coincidence (for example the seed lying on top of a leaf) because it is perpendicular to the frond stem and the attachment is pretty clear on both halves of the fossil. We were fortunate to collect both halves and this specimen is very well articulated. (Nancy actually discovered this by splitting open a fragment that was cast aside at one of the small pits dug by other fossil hunters - we have found a lot of our most exciting and rare fossils by segmenting pieces that are already lying on the ground around this site - of course, there are thousands of fragments so it takes a keen eye, it helps to know how the different structures relate to each other so if there is a cluster of a certain species you know what to look for and where, and always it helps to have some luck. We have emailed our photos to the paleontologists at UC-Berkeley who have an artist's rendition of this seed/attachment on their site (see my post below). They mention on their site that not many attached alethopteris seeds have been found. More photos of this are included in my post below. Unidentified Seed 1a and 1b. This is an isolated fern seed not associated with a specific type of fern leaf. Both halves are shown. It has a distinctive groove in the top. Seed 2. Another isolated fern seed. Seed 3. Another similar fern seed. Seed 4 is a different shape - a round seed with serrated edge. Seed 5 is another different shape that we see frequently although it's usually not very well articulated. Is this a seed or something else? It's always this shape. Seed 6a and 6b are both halves of the same seed and have the same shape (groove at the top) as Seed 1a/1b above. Seed 7 is another isolated seed. Thanks in advance for your opinions!

Nancy and I revisited St. Clair (the large depression south of Burma Road) on Aug. 4. Only two other collecting teams were there - some young people who were excavating and found a lot of nice pieces, and a middle aged couple. The bear and her cub were not in sight - probably cooling off in a stream somewhere. It was 91 degrees and higher in the pit but afternoon clouds and a strong breeze made the weather comfortable. We continue to improve our excavation techniques, which are nothing fancy - just a rock hammer and chisels, but we work to extract larger (1 to 2 feet) sheets intact, which we fragment into large thin pieces. Techniques we've seen other people use include "mining" fossils in large pits, and carving out large round slabs. Some people are excavating under trees which is not cool - we hard that's what got the site closed to fossil collectors several years ago. This was a successful trip. We only spent half a day there, but met our goals. Last trip, I brought back a 2 ft. long section covered with orange and yellow fern fossils. This trip I was able to secure most of the other half of that section which is equally impressive (see photo below), plus we collected some white fossils in large (9 inches to 1 foot or longer) sections suitable for display on a shelf or on the wall. I worked to get some sections that are thin and light enough to frame but getting larger pieces intact is an art. My impression is that a lot of people seem to be using hammers and just hammering away at the substrate. This produces piles of tiny fragments and partial fossils which are discarded. This also explains why there are so many small pieces scattered everywhere. We sorted through the throwaways in the pits - if you look closely and know what to look for you can find some scarce specimens that include sections of bark from Calamites, Siggularia as well as bright white, orange and yellow ferns, groups of fossils that are a bit harder to find such as Annularia, etc. A general observation - there is a LOT of shale to excavate and explore, including many pits started by other collectors. Some look hard to extract but are easier than they look, but it requires a hammer and chisel and some careful cutting around the periphery to get out larger pieces - and often you have to remove some overburden that covers the fossil layers. Some pieces look smooth or round but some strategic hits with a chisel will segment them into small manageable sheets that sometimes come out larger than expected. It takes more time but you get more intact fossils. Also, many times I'll pull out a large sheet of shale thinking it looks totally empty or with only a few fossils visible, and will chisel it into increasingly smaller sheets with no results, then when I chisel open the very last layer, I'm rewarded with a really nice dense fossil mix. Nancy continues to use her keen eye to find unusual shapes and patterns - some of which are included in the Fossil ID section. She mentioned finding a "feathery" fern that she discarded because it looked too fuzzy - and later going through a fern book we saw that this was a feathery fern called Odontopteris. Which just goes to show that it pays to bring home stuff that looks interesting. I also found two very large neuropteris leaves - about 9 to 12 inches - but they didn't survive the segmenting process. We keep forgetting that many large fossil trees had very large leaves but they are hard to find the way most people work on smaller pieces. We don't want to move up to commercial-size excavations which defeats the purpose of this being a hobby, but we do want to keep working with our hammers and chisels to remove display size pieces. Didn't have much time to shoot photos but a few images are included here. Number 4 shows an Alethopteris and Annularia on the same fossil, which is a nice mix. The next images show "display pieces" from our trip, and a yellow fern. You can see more in our post in the Fossil ID section.