Street-level imagery tracks survival of 2,884 planted Philadelphia trees

Researchers demonstrated multiyear survival monitoring using street-level imagery for 2,884 planted trees in Philadelphia. The analysis connected survival outcomes with site conditions, neighborhood characteristics and planting season.

Tree planting programs depend on survival to deliver sustained shade and stormwater benefits, not simply on planting totals. Imagery-based monitoring can supply mortality data to help managers evaluate programs and inform site enhancements and early maintenance.

A study in Arboriculture & Urban Forestry demonstrates how street-level imagery can support multiyear monitoring of planted urban trees, a task the authors describe as time-consuming in the field. Researchers tracked 2,884 street trees in Philadelphia and found that 7.5% were dead or removed by the first summer after planting. Mortality between the third and fourth summers was 3.5%. Logistic regression models associated higher survival with less surrounding impervious surface, lower neighborhood social vulnerability and fall rather than spring planting. These are associations, not proof of causation. For urban forestry managers, the findings support using survival monitoring to inform planting schedules, site improvements and establishment maintenance. The contribution is a demonstrated imagery-based monitoring approach, rather than a new automated detection system.

Evidence supplied by Arboriculture & Urban Forestry.