The Benefits of Urban Trees

July 29, 2016

park-1086190_1920As I was walking down the street in downtown Greensboro I noticed that something was different. I approached The NewBridge Bank ballpark, home of the Grasshoppers, and I could hear the busy construction workers on the east side tirelessly sweating at what is supposed to be a fantastic new business park. But when I saw the field being watered, the difference that I noticed really started to bother me. What was it? I couldn’t quite put my finger on it so I kept on walking. The street seemed more appealing and lively. It was brighter and honestly just a nicer environment. But why? And then I saw them – the trees! There were more Maple and Hawthorns. The city had planted urban trees throughout the nearby areas of construction.

As most people know (myself among them), planting trees along streets and in city parks has a ton of benefits. But I started to wonder, why exactly would a city pay to have them planted in the first place? Just so someone like me can walk around and say the city looks prettier? Well, actually, that turns out to be one of the reasons but there are lots more.

After a lot of digging through academic journals, I found tons of scientifically-sound reasons to plant trees in urban areas. In the past, reports typically cover the damages and nuisances of urban trees but what we less often see is the reports of the benefits of these trees. Below we’ve broken them up into three main categories: economic, social, and environmental.

Economic benefits

Trees save energy and therefore money.

  • A 10% increase in tree cover can reduce total heating and cooling energy use by 5–10%.
  • Even a single tree was found to decrease annual heating costs by 1.3% and cooling costs by 7%.

Trees are better for business.

  • Treescaping can increase business income by 20%.
  • They can increase economic stability. The condition of a the community’s trees is one of the first impression a visitor sees of that community.

Trees increase property values.

  • In Alabama, 75% of residents indicated the presence of street trees influenced their choice of a new residence.
  • House prices in Perth, Australia, were higher by an average of 20–30% when there was tree cover on the public space next to, or near, the property.

Trees are actually worth something.

  • The annual net benefit per tree is between US$21 and $159, most often around $50.

Environmental benefits

Trees increase livability of an area.Urban Forestry Tree

  • They reduce storm-water runoff, improve air quality, provide share, ameliorate the heat-island effect and enhance biodiversity. In short, it’s a more pleasant place.

Trees reduce impervious surface area.

  • Urban runoff from summer rainfall is much higher from asphalt (62%) than from surfaces with tree pits (20%) or turf (<1%), highlighting the effect that trees can have on storm-water reduction.

Trees increase biodiversity.

  • Street trees provide habitat for urban fauna, and some fauna species are so well-adapted to urban environments that they are more abundant in cities than in surrounding natural vegetation.

Trees reduce carbon and other pollutants in the atmosphere.

  • Capturing airborne pollutants including ozone, nitrogen oxides, sulfur oxides, sulfur dioxides, carbon monoxide, carbon dioxide (CO2) and particles less than 10 μm in size.

Social benefits

Trees are better for our mind and body.

  • Greenspace in an urban environment promotes contact between community residents, encourages physical activity, reduces stress and stimulates social cohesion.

Trees may slow traffic.

  • Trees may reduce the speed of drivers, therefore reducing the frequency and severity of crashes.

Trees may make us safer.

  • Reduced crime and increased public safety have often been associated with urban areas that have a high abundance of street trees.
  • A 10% increase in the amount of tree cover has been associated with a 12% decrease in crime.

leaves-432325_1920Pretty crazy, if you ask me. I knew trees were valuable but who would have guessed this valuable? As a bonus: urban trees can actually make the wait for the bus feel shorter. The more mature trees present, the shorter you’ll feel you’ve waited for the bus. And the best thing about them, trees are on the job 24/7, they never need a break!

Up next week we’ll look at what an urban forestry management plan is and start to scratch the surface on the different kinds.