Department of Biology

You won't find it listed in "The Woodland Campus" walking tour guide. Quite possibly the oldest tree on campus—it went mostly unnoticed in the south lawn of the Biology Building for many years. It was moved to a more prominent location in November 2020.

The old "tree" is actually a fossil of a large Sigillaria stump.

Sigillaria lived around 320 million years ago. The ancient treelike plant grew rapidly to nearly 100 feet tall in the dense Indiana swamp coal forests. It became a major contributor to the coal mined in Indiana as it died and decayed—becoming peat and eventually coal millions of years later.

The extinct genus looked somewhat like today's palm trees. Long, thin leaves grew in a spiral along its single or occasionally forked trunk. The leaves—which were attached directly to the trunk— persisted only at the trunk's top near its growing tip. Where the leaves had fallen off of the lower part of the trunk, characteristic diamond-shaped scars (that can be seen in some fossils) were left in vertical rows by the old leaf bases as the trunk expanded. The plant produced spores (not seeds) in cone-like structures attached to the stem.

The stump fossil was formed when the plant died; sediment filled the hollow space where the center rotted out within a ring of strong and thick bark. The hardening of the sediment produced the cast of the trunk.

The Sigillaria cast displayed on the IU Bloomington campus was collected in 1972 in southwestern Greene County, Indiana, by IU Vice Chancellor and Dean of the Faculties Henry Remak and IU Professor of Paleobotany David Dilcher.