How Trees Benefit the Ecosystem All Winter Long
Trees in Winter
A tree ecosystem is active even in winter when many trees lie dormant. This is why having a variety of tree species in a location is important. Certain trees can perform certain services in the summer, others in winter, while all trees contribute stabilizing benefits year-round. Here, we’ll go over which ecosystem services trees perform in the winter that keep our environments livable.
How Do Trees Benefit Our Environment Throughout the Year?
Throughout the year, trees maintain and improve our environment in many ways. In the spring and summer, all kinds of trees are actively growing, sprouting their leaves and flowers, and gaining height, width, and density. As they grow, trees absorb carbon and pollutants from the air and release oxygen. Their leaves also intercept larger air particles, contributing to a filtration effect that helps keep the air clean. As they gain height, leafy trees cast shade on the surrounding area, effectively lowering temperatures. They absorb moisture from the ground and release it into the air, which also helps cool the immediate location.
Trees that lose their leaves in autumn before they go dormant for winter help build soil; when those leaves stay where they fall or are gathered and then reapplied for mulch or compost, they break down and contribute nutrients and bulk to the ground. Before they fall, however, the beautiful shades of the leaves create an aesthetic atmosphere that we enjoy throughout the season. Evergreen trees that keep their green foliage all year contribute to this visual interest in every season.
Whether deciduous or evergreen, trees perform certain ecosystem services year-round, like soil stabilization, water management, temperature regulation, and habitat and food provision for wildlife. As temperatures drop in the fall and winter, all types of trees continue to perform these essential ecosystem services in one way or another.
Habitat for Animals
Trees provide a habitat for animals in every season of the year and are used differently by wildlife, given the nature of each season. Summertime trees provide green cover and refuge from ground predators, as well as materials for nest-building. In the winter, however, their roles as shelters take on new importance for wildlife that don’t migrate. Some animals go into hibernation, and trees create safe locations for these animals to sleep throughout the winter undisturbed. Small animals like chipmunks, ground squirrels, snakes, groundhogs, and woodchucks may dig out small dens and burrows underneath tree roots, under logs, and inside the thick trunks of hollowed standing trees. While bats often hibernate in caves and the attics of buildings, some will find a small hole or cavity in a tree to spend the winter.
For wildlife that don’t hibernate in the winter, trees are protected lodging for birds like owls, jays, cardinals, chickadees, pheasants, doves, and many other species that don’t leave for the colder months of the year. Similarly, many mammals don’t hibernate; foxes, rabbits, squirrels, and other mammals also make their winter homes in dormant trees. They may find refuge under the dense foliage of evergreen trees, like pines or junipers, too. This is where deer find shelter since they don’t dig dens like other mammals, but they do need a safe place to stay out of the wind, rain, and snow while remaining hidden from predators.
Food Sources for Animals
Throughout the spring, summer, and fall, trees produce seeds and nuts that certain animals store for the winter. Small mammals like squirrels and mice will gather and store food for the winter (some birds will do this, too). Then, they try to remember where they stored their buried treasures, whether in the ground or in a tree, and go back throughout the season. Sometimes, these are forgotten about and sprout into seedlings in the spring. The food these animals are able to find, however, provides essential fats, nutrients, and energy to get them through the coldest months.
Other animals don’t store food for the winter but survive on forage they are able to find. Deer and rabbits, for example, will eat bark, twigs, buds, nuts, acorns, and winter foliage and berries for energy when leaves, grass, and other summer greenery are unavailable. Omnivorous birds may be lucky to find insect larvae in trees or under logs in the winter, while carnivorous animals like coyotes, foxes, and owls hunt for small mammals and insects in the winter just as they do in the warmer months. In every season, trees support the various levels of the food web that keep ecosystems in a good, balanced state.
Temperature Regulation
Deciduous and evergreen trees both play their parts in managing the winter cold. While bushy foliage helps cast shade in the summer, trees that lose their leaves for winter allow sunlight to warm up the ground and buildings during the day. Conversely, evergreen trees, which stay dense and green in these cold months, can reduce wind flow at the ground level. Spruces, pines, and other evergreens can be planted in rows and clusters as windbreaks, or barriers that reduce the cooling effect of wind on houses. Without a windbreak, homes may be colder and drier from winter breezes, and snow can more easily pile up around a building, blocking passages and entrances or causing water damage as it melts and/or freezes.
Water Retention
Although more flooding issues occur during warmer months, excess water can also be a problem in the winter. Winter rains and melting snow can damage buildings by affecting the foundations and facades, particularly in freezing temperatures. Moisture may work its way into cracks and freeze, enlarging those cracks and eventually leading to chipping and crumbling away of the stone, which can then create issues with moisture seepage and mold inside of the building. The roots of trees hold soil in place, which then is better able to absorb moisture throughout the cool, rainy, and snowy months of the year.
Bushy evergreens that block wind can also collect rain and snow, keeping a portion of the moisture away from buildings. This also helps the tree, as any moisture it intercepts will end up in the ground under it and can be absorbed by the roots.
Soil Stability
In addition to managing groundwater around buildings and pavement, roots hold soil in place that might otherwise be lost to cool-season winds and rain. While topsoil loss affects the health of your yard and garden, soil buildup around a home’s foundation can lead to the same problems associated with moisture buildup at the base of a house. If soil collects along the foundation of a house, it will hold more water there, which can work its way into the stone components and interior parts of a home. Having trees with extensive root systems in your yard can help keep your soil from shifting when it’s more exposed from a lack of green cover.
Plant Trees for Year-Round Benefits
The benefits of trees may be particular to a season or a year-long contribution, which means that every tree planted helps our local ecosystem remain robust year after year. If you’re looking for new saplings to add to your yard, consider purchasing one (or more!) through the Nashville Tree Conservation Corps’ annual tree sale, open October through February. To get involved with the NTCC’s volunteer activities, reach out to us through our website. And for regular information on canopy care around Nashville, sign up for our email newsletter!