Skill Builder: Dead Wood Supports Life
That rotting stump in your yard could be a critter condo.
By Mary O. Parker
That rotting stump in your yard could be a critter condo. Would it surprise you to learn that dead wood sustains as much life as living trees? In fact, what looks like waste to us supports hundreds of Texas species.
Dead trees left standing to decompose naturally are called snags. Logs are what we call wood that’s down on the ground. Think about including both in your backyard to mimic what occurs in nature.
Snags provide plenty of crevices and hollows where critters can live, hide or store food. They also make great places for birds, such as woodpeckers, to find good eats, or spots for eagle-eyed raptors, like red-tailed hawks (which keep rodent populations in check), to perch in search of supper.
In Texas, snags attract eastern bluebirds, Carolina chickadees, pileated and red-bellied woodpeckers, nuthatches, barred owls, tufted titmouses, tree swallows, warblers, wrens and raptors, as well as raccoons, squirrels and mosquito-eating bats. Many songbirds, like our state singer, the mockingbird, especially like to show off when they’ve got snags for stages.
“Snags are important to woodpeckers and nuthatches for not only foraging, but for nesting and roosting, too,” explains Cliff Shackelford, a nongame ornithologist with the Texas Parks and Wildlife Department. “Their abandoned cavities also provide homes for other vertebrates and invertebrates, including over 80 species of birds in North America that are secondary cavity nesters, which need hollows but cannot create them.”
Once the snag rots enough to fall to the ground, it creates a new ecosystem where moisture plays a crucial role. For example, holes created by a woodpecker’s bill become tiny “tanks” in wooden pastures that give rise to fungi, microorganisms and invertebrates such as earthworms and fireflies. These creatures, in turn, sustain salamanders, toads, anoles, tree frogs, birds and others. As logs decompose, they recycle nutrients back into the soil, all while coexisting in symbiotic relationships with the animals they support.
Michael Warriner, inverterbrate biologist with TPWD, emphasizes the substantial contributions that dead wood makes to forest biodiversity.
“Of the various organisms that make use of dead wood, insects represent one of the most species-rich and abundant components,” he explains. “Some insects spend the majority of their life cycle living within, and feeding on, dead wood. Others feed only on wood-decaying fungi or prey on other insects within dead wood. Dead wood is critically important to these insects, and reductions in this resource can lead to real conservation issues for those species.”
If your log hasn’t yet seen the handiwork of a woodpecker or needs help holding its water, nudge nature along by drilling a hole or two. You can also fast-forward the ecosystem by encouraging native vines to get attached and by trapping soil along the wood’s edge.
What if termites also find your log lovely? Of the two types of termites, subterranean and drywood, chances are that any residing in this special habitat will be the drywood sort, which usually stay put (to be eaten by toads, birds and other wildlife) unless a trail of moisture entices them elsewhere. Thus, to keep them from adventurous walk-abouts, place logs a reasonable distance from unintended water sources.
Along the same lines, keep logs and snags from resting against structures to discourage fungi or unwanted guests from coming in contact with your abode. Of course, make sure snags don’t hover over a neighbor’s fence, yard or vehicle. If you find that the snag must be sawed, don’t forget to use it as a log.
You don’t need acreage to bring the dead to life; a snag or log in even the smallest of yards can add animation. And, when company comes for a patio dinner and the words “a lump on a log” arise, you’ll know it’s not a lack of vitality they’re discussing — it’s that cool critter someone spotted in your backyard!