Diagnosing Maple Leaf Scorch: Bacterial vs. Physiological

Mark's 9-inch-circumference maple (possibly a 'Fire' maple) loses color, browns, curls, and drops leaves from the top down each year. He's tried Miracid and extra water, but the problem persists even in dry weather.

Two Types of Leaf Scorch

Physiological Scorch

Water evaporates faster than roots can replace it. Causes: soil compaction, drought, poor root development, or root damage.

Bacterial Leaf Scorch (BLS)

Caused by Xylella fastidiosa, a bacterium that clogs the vascular system. Symptoms mimic physiological scorch but progress yearly, eventually killing the tree. No cure exists.

Mark's Case Points to BLS

Top-down progression, annual recurrence, and lack of response to watering or acidifiers strongly suggest bacterial leaf scorch. The tree will likely decline over several years.

Action Plan

Plant a replacement tree nearby now. Choose a species resistant to BLS and suited to your soil. Maintain the current maple with proper watering and mulch to reduce stress, but accept its limited lifespan.