The power lines that run along the road don't normally make for interesting scenery, but sometimes they contain an eye-catching surprise. In addition to the brightly colored balls strung up along the wires, you may have spotted dangling hunks of wood through your car window. Unlike the visibility marker balls used by utility companies, the "tree chunks" hanging from power lines don't serve a practical purpose.
As The Washington Post reports, any wood you spot hanging above the road from a power line is a leftover piece of tree. When a growing tree reaches an obstruction, the wood and bark sometimes form around it instead of bending in a different direction. This is the case with some trees growing beneath power lines.
Vegetation near power equipment can cause problems, which is why utility companies hire maintenance workers to keep the areas around power lines clear. If a tree has already started growing around a wire, a worker may try to get rid of as much of it as possible. To avoid accidentally damaging the line and disrupting service, they'll leave a small piece of log behind. Over time, the wood will decompose and fall down on its own.
You rarely see chunks of trees around electricity lines. These wires run along the tops of utility poles, and they're more prone to triggering accidents than the wires for telephones. For this reason, electricity maintenance workers are quick to cut any stray vegetation before it reaches their wires. Telecommunications companies have their own crews that may follow more relaxed maintenance schedules than electricity providers. This is why the hanging chunks of trees you see are usually attached to the lower lines on utility poles.
If you run out of podcasts to listen to on your next car trip, you can entertain yourself by paying closer attention to the landmarks you pass every day. Here's the purpose behind those domes you may have noticed on the side of the highway.
[h/t The Washington Post]