Vehicle-tree collisions responsible for 25% of deaths on German country roads

No room for driver error on tree-lined roads

Aug 10, 2021

Which roads are the most dangerous? Official accident statistics give us a clear answer to this question, for Germany at least. For years now, by far the largest number of fatal road accidents have occurred on country roads. They account for around 60 percent of all road deaths in Germany – 1,592 people in 2020. One of the most common hazards is collisions with roadside trees.

  • Rural roads significantly more dangerous than motorways and urban traffic
  • Tree collisions among accident categories with most serious consequences
  • DEKRA experts urge not to plant new trees alongside roads
In 2020, more than 400 road users died because of vehicle-tree collisions on rural roads in Germany. Around a quarter of deaths on country roads are caused by crashing into trees – a figure that has been consistent for years. The absolute number of accidents did fall during the pandemic in 2020. However, the percentage of vehicle-tree collisions remained virtually unchanged.
“Vehicles crashing into trees at speeds that are usual for a country road are among the accident categories with the most serious consequences imaginable,” says Peter Rücker, head of DEKRA Accident Research. “The force of the collision is concentrated in a very small area and releases a huge amount of energy. Even in brand-new, state-of-the-art vehicles, the chances of surviving a crash involving a tree at 80 km/h are very slim.”
Especially where trees are regularly spaced close to the road, just one small lapse in concentration can be deadly. “If someone goes off the road, most of the time, the vehicle’s direction of travel will only be a few degrees away from the course of the road,” the DEKRA expert says. “In those situations, a line of trees has the same effect as a wall – the probability of a collision is close to 100 percent.” In other words, tree-lined roads leave practically no room for error.
So, there is a negative side to picturesque country scenery. But the accident specialist does not see this as reason to dust off the chainsaws. “By no means are we talking about a big tree-felling campaign,” Rücker says. “However, it is very important to think carefully about how we can make roadsides safer on country roads.”
A first, important step in his eyes is to avoid planting new trees alongside rural roads: “Ecologically speaking, there’s nothing particularly valuable about having a tree directly next to a road. Wherever possible, roadsides should be clear of obstacles and allow vehicles to coast to a relatively safe stop in an emergency.” In this context, experts often talk about “forgiving infrastructure” that can accommodate human error.
This may include construction measures; for instance, traffic barriers used to fence off rows of trees or isolated trees. And to ensure that motorcyclists are also kept safe in the event of a crash, these traffic barriers should always be fitted with underride guards.
A general speed limit of 80 km/h (50 mph) rather than 100 km/h on narrow country roads is also under discussion in Germany. In the DEKRA expert’s view, this change would be a step in the right direction: “We have always advocated ensuring that speed limits are suitable for the specific conditions of each section of road on a case-by-case basis. It does not make sense to treat a well-built, wide, straight country road the same as a section that is winding and narrow.” The more logical a speed limit is to road users, the likelier they are to obey it. “Ultimately, depending on the situation, even 80 km/h may still be too fast for some sections.”
The basic, commonsense rules for motorists and motorcyclists also apply to driving on country roads: anticipate potential risks, do not drive too fast, keep your distance from the vehicle in front, err on the side of caution. “The minimal time we potentially save by doing a reckless overtaking maneuver, for example, is disproportionate to the risk it poses to ourselves and others,” Peter Rücker says.