Willow Tree Partial Leaf Yellowing: Water Needs and Trunk Check

Symptom Pattern

15-ft willow: middle leaves yellow, top leafless, one branch green. Sudden onset in summer.

Primary Suspect: Water Deficit

• Willows (Salix) are high-water-demand trees.
• Yellowing from interior outward = drought response (shedding least-efficient leaves).
• Top dieback = hydraulic failure—water not reaching crown.

Secondary Check: Trunk Damage

• Inspect base for cracks, borers, mower injury, cankers.
• Bark damage → internal decay → one-sided symptoms.

Action Plan

1. Deep Water NOW: Slow trickle 3–4 hrs at 3–4 points under drip line. Repeat weekly until rains return.
2. Mulch: 3" to drip line.
3. Trunk Inspection: Photos to arborist/Extension if damage found.
4. Fertilize? Only if soil test shows deficiency. Not now.

Recovery Signs

New leaf emergence at tips within 2–3 weeks of consistent watering = good prognosis. Continued top dieback = vascular/root failure.