I go for a series of short walks down the road where we live most days during the summer. In the winter when the snow is piled over my head on the side of the road…not so much. But, since we live in the country, my walks always allow me to see and hear some sights and sounds of nature.

Nature comes in many shapes and sizes. One part of nature that I have been observing over the past few years never moves and I have never heard it make any sound whatsoever. But still, this part of nature is very valuable for many reasons. It goes by many names, but I call it a snag.

Yes, that would be a dead or dying tree. Death is a part of life and with trees, the dead and dying provide many environmental benefits, most of which are not really appreciated.

In forest ecology, a snag refers to a standing, dead or dying tree, often missing a top or most of the smaller branches. In freshwater ecology, it refers to trees, branches, and other pieces of naturally occurring wood found sunken in rivers and streams.

Snags are an important structural part of forest communities, making up 10–20% of all trees present in old-growth tropical, temperate, and boreal forests. Snags and downed coarse woody debris represent a large portion of the woody biomass in a healthy forest.

In temperate forests, snags provide critical habitat for more than 100 species of birds and mammals and are often called ‘wildlife trees’ by foresters. Dead, decaying wood supports a rich community of decomposers like bacteria and fungi, insects, and other invertebrates. These organisms and their consumers, along with the cavities, hollows, and broken tops make snags important habitat for birds, bats, and small mammals, which in turn feed larger mammalian predators.

Snags are an optimal habitat for primary cavity nesters such as woodpeckers which create most cavities used by secondary cavity users in forest ecosystems. Woodpeckers excavate cavities for more than 80 other species and the health of their populations relies on snags. Most snag-dependent birds and mammals are insectivorous and represent a major portion of the insectivorous forest fauna and are important factors in controlling forest insect populations. There are many instances in which birds reduced outbreak populations of forest insects, such as woodpeckers affecting outbreaks of southern hardwood borers and spruce beetles.

Every tree dies eventually, and its ecological value continues long after the last leaf falls. Whether it still stands, is reduced to a hollowed stump, or exists as downed wood, most of its “life” occurs in a complex, interesting, unseen world. Imagine a time-share that is used by different species, for vastly different purposes, in every stage of its demise. Most species that use snags are associated with those that are about 15” in diameter though there are many benefits from smaller trees too. No man-made structure matches the ecological usefulness of a sizeable dead tree; and few living things are as overlooked and unappreciated, except of course by wildlife and the vast number of inhabitants at work on its remains beneath the soil.

Nature “gifts” dying trees to enrich habitats. A dead tree is a legacy that can take dozens of years to replace, and in many cases, it will never be replaced. Whenever a tree is cut down needlessly and hauled away prematurely, we short-change our forests and our planet. Dead trees represent one of the finest examples of nature giving back to the environment. A study of a snags relationship with wildlife and organisms above and beneath the soil is a profound example of the fact that individuality and independence within our ecosystems is an illusion.