As the weather turns chilly, even here in the Sonoran Desert, I keep seeing a particular word pop up: marcescence. This phenomenon is defined as plants hanging onto their dried and dead leaves through the winter rather than shedding them in autumn. Beech, oaks, and witch hazel are some of the plants that display marcescence. Learn more about this phenomenon, and potential reasons why it is advantageous to plants, in an article from University of Maryland Extension. You might also check out this recent New York Times article that digs into what cues plants to shut down in winter.
As for Nature's Notebook, once a leaf is dried/dead, it no longer counts as a leaf, so you would report "no" for Leaves and Colored leaves for these dead leaves that still cling to the tree. And what should you report if these dead leaves fall off your plant later on in the winter? To answer this question, one only needs to look at the definition for Falling leaves, which states: Do not include fully dried or dead leaves that remain on the plant for many days before falling.
Photo: Dead white oak leaves cling to a branch, Credit: SeashoreToForestFloor.com