When fall arrives for most deciduous trees, the plant hormone ethylene regulates senescence, the aging and withering of leaves. Dead leaves naturally fall to the ground through a process known as abscission.
Sometimes though, deciduous leaves stay on a tree through fall, winter, and early spring, and only fall to the ground when new leaf buds start growing. When dead leaves do not fall but overwinter, the unusual pattern is known as marcescence. I have seen it in witch hazel trees, in pin oaks, on low European beech tree branches, and on young European beeches.
On my street, three Fagus sylvatica (European beech) were planted in March 2019 and I have
been photographing them and watching the process called marcescence.
had turned a warm, rusty brown, but had not fallen.
In mid-March 2021, the tree looked much the same,
though the leaves had shrivelled and lost some of their warm colouring
By May 5, almost all the brown leaves had fallen
and I noticed the first new leaf was breaking bud.
A week later, on May 12, the whole tree was in leaf! I could barely believe it had happened in such a short time that I checked the photo dates several times. It would have been fascinating to have watched the beech daily over that week as it morphed from twiggy and brown to leafy and green.
Text and Photos: vmg student 2021 Nina S.
