Tree-lined streets aren’t just for inflating property rates and hanging lost gloves from anymore. A new study from Columbia University found that children who lived on tree-lined city streets suffered asthma rates of only nine percent -- extremely impressive, compared to an overall rate of 50% across most urban areas.

Asthma, now the leading cause of hospital admittance for New York City children under the age of 15, has been on the rise for decades. For those about to remind me that correlation does not prove causation, the study also corrected for sources of pollution, population density and affluence, yet still found that the beneficial effect of the trees remained.

The investigators did concede that the nature of the connection between trees and asthma rate is unknown. Some have suggested that the trees provide added incentive for children to go out and play, while others speculate that the trees improve air quality.

Pet theories and additional wild guesses are welcome in the comment section.

Photo by Dash Panache