Saving old trees may protect people's health more than planting new ones, study of Chicago neighborhoods finds

Four trees in a green park with a bench overlooking the city of Chicago.

Losing mature trees from a neighborhood may be a matter of life and death, a new study suggests.

The research, published Aug. 5 in the journal GeoHealth, tracked tree canopy cover and mortality across Chicago neighborhoods over 11 years. It found that it wasn't the number of trees in a neighborhood that was most strongly linked to residents' survival — it was whether the overall tree canopy was shrinking or growing from one year to the next.