We found this fossil about 30years ago in a field in Swalwell, Tyne and Wear. My little girls is doing Fossils at school so we thought she could take it in but we would like more information on it. We think it has something to do with trees but we aren't 100% and would love to hear from someone who's in the know. Any information would be appreciated. Thanks
Most botanical or zoological names comprise two words: genus and species. In some cases, individuals can be identified only as far as genus, either because the specimen does not provide enough information or because science simply does not know enough to enable species to be defined. For instance, given just a pine needle, we can identify it no better than Pinus.
With fossil trees, information was (and many cases still is) very limited. So we have just the names of genera by which to refer to them. Stigmaria is an example. Over the decades, we have come to know more. We know that Stigmaria specimens are always roots; but we also now know those roots are from more than one genus of tree. Oh dear - that's not how the naming system, in its purest form, was supposed to work!
But some of the prime purposes of naming are to enable scientific discussion and amalgamation of related observations. Even though Stigmaria and other such 'form genera' are different in concept, they are still of practical value.
If you search for 'form genera' in the second link, you'll see further explanation in a diagram and its following paragraph.