Tree-Lined Streets Associated With Lower Childhood Asthma Rates

Young children who live in neighborhoods with lots of trees have lower rates of asthma than children who reside in areas with fewer trees, a new study finds.

Researchers looked at asthma rates among children aged 4 to 5, and asthma-related hospital admissions for children up to age 15, in 42 service districts of New York City. Asthma is the leading cause of hospital admission among children aged 15 and younger in the city.

The researchers compared the medical data to information about the number of trees in each of the districts, along with sources of pollution, population density, and racial and ethnic composition.

Nine percent of the young children in the study had asthma, and the city had an average of 613 trees per square kilometer. Asthma rates decreased by almost one-quarter for every standard deviation increase in tree density, equivalent to 343 trees per square ...