Bud scales are modified leaves that are typically tough and overlapping, providing a protective barrier against:

* Desiccation: They prevent the bud from drying out.

* Freezing temperatures: They insulate the bud and protect it from cold damage.

* Herbivores: They deter animals from consuming the delicate developing tissues.

Once the bud is ready to emerge, the bud scales usually fall off or are pushed aside by the growing leaves and stem.