It is late January and you find yourself in a wood. Everything looks barren, but yet you note some trees holding onto their spent leaves from last summer – “persistent leaves” is the horticultural term. In the eastern deciduous wood, we associate this with beeches, oaks, sugar maples, and the less common, hornbeam.

The scientific word is “marcesence” – the retention of dead organs that are normally shed. It can refer to flowering and fruiting parts as well, but retained lifeless leaves are the more obvious.

American Beech, Highland Cemetery Nature Trail, Fort Mitchell, KY.

They provide a background rattle as you walk through the wood on a breezy winter day. But what is the evolutionary reason for this to occur? Fact is, no one really knows. There are many theories and it is probably a combination of the following:

Protection of leaf buds from harsh winter weather and desiccation.

Delayed source of nutrient rich and moisture conserving mulch when the leaves are finally shed in spring.

Deters browsing by deer of the nutritious buds (the dead leaves are less nutritious and noisy to browse on), which may explain why it occurs more commonly on the lower branches.

Retaining the leaves may speed up decomposition by photodegredation (exposure to sunlight), making them a more immediate source of nutrients when they do hit the ground.

Trapping snow and moisture to allow for spring growth.

White Oak, Sally Brown and Crutcher Nature Preserve, Lancaster, KY.

It has been my observation that leaf retention in the winter is generally seen in younger trees, as noted in the above photos. If it is seen in more mature trees, it will only involve the lower branches, which horticulturally have juvenile characteristics (they usually do not bear fruit). Were they just waiting for the overstory to shed their leaves and provide a last gasp at photosynthesis? That is the theory of some.

When I see an abundance of persistent leaves in a wood, I interpret this as a wood transitioning to a more mature Beech, Oak, and Maple forest, as these young hardwoods stake their claim to the terrain, and begin to out compete the pioneering tree species like Redcedar, Ash, and Locust.

Sugar Maple, Stanbery Park, Cincinnati , OH.

A photo of a young American Beech with persistent leaves and “lance” shaped buds, both identifying characteristics in the winter and early spring. (Stanbery Park, Cincinnati, OH).

Every season is hiking season, and contemplation of the role of persistent leaves is demonstrative of that . Savor the moments that you find yourself in the woods, and consider, taking someone who would benefit from the solace of nature.

One last photo of a young oak with persistent leaves. (Sally Brown and Crutcher Nature Preserve, Lancaster, KY).

Photo credits to Peggy Juengling Burns