Diagnosing Decline in Chinese Pistachio Trees After Excessive Rain

Situation

One of two Chinese pistachios (20 ft apart) in sandy Texas soil is wilting, leaves brown but attached. Neighbor's pear shows similar blackened leaves. Record rainfall and a suspected drainage funnel along the fence suggest waterlogging.

Likely Causes

Phytophthora root rot or other water-mold fungi thrive in saturated soils. Both pistachio and pear are susceptible. Symptoms include wilting, leaf discoloration, and death despite adequate water.

Action Plan

Hire an ISA-certified arborist to assess both trees and the neighbor's pear. Treat with a systemic fungicide (phosphonate) via soil drench or injection. Improve drainage if possible. Split costs with neighbor for coordinated treatment.