Feb 7, 2016
These trees that have stubbornly held on to their dead leaves all winter (top to bottom: northern red oak-Quercus rubra, white oak-Quercus alba, American beech-Fagus grandifolia) are all displaying a phenomenon called marcescence. This means that the abscission layer at the petiole (which involves active cell growth) does not form until late winter or early spring.
This trait is strongly genetically controlled and is common in the Fagaceae family. However, non- marcescent deciduous trees will hang on to their leaves if the tree, branch or leaf dies before autumn and before an abscission layer can form.