An article published today in the Journal of Epidemiology and Community Health shows that children who lived on streets lined with trees have lower rates of asthma, reports Medical News Today.

The study looked at asthma rates in children ages four to five as well as hospital admissions in children up to age 15 in 42 health service districts in New York City. This data was compared to city data on the number of trees growing, pollution sources, racial and ethnic factors, and population density.

Researchers discovered that a total of 9% of young children had asthma, and that there was an average of 613 trees per square kilometer in New York City. For each standard deviation increase of tree density (343 trees per square kilometer), asthma rates fell by a quarter in the age group examined. Even when considerations of pollution, affluence, and population density were taken into account, the pattern remained. Interestingly, the pattern held just for this young age group; once children were older, lower asthma rates did not coincide with higher tree densities.

Authors of the study speculated that the trees may help either by improving air quality or by encouraging children to play outdoors. That makes it even more important to take care of your outdoor space such as tree trimming. You can check out this top article on how to take care of your trees.

For more on how to cope with asthma, see the Asthma Solution Guide, Asthma Statistics, and Asthma FAQ.