PHOTOJOURNALISM - TrockStock

Urban Forestry Institute employee Brent Cooper, center, is assisted by Corbin Sladkey-Gerdes, left, and Brody Curtis-Erhardt, as they measure the diameter of a green ash tree at Hilltop Primary School in Minnetrista Wednesday, April 27, in celebration of Earth Day. Measuring trees helps professionals determine age, health and amount of care needed to keep the trees in top shape.

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