African Sumac Dieback: Upper Crown Death and Surgical Pruning

African Sumac Top Death: Disease or Environmental?

A 3-year-old African sumac (Rhus lancea) with healthy lower multi-trunk growth but dead, brittle top crown has crown dieback—likely disease or environmental stress in the upper canopy.

Diagnostic Approach

• Lower health = roots/trunk okay.
• Upper death = localized issue (disease, borers, lightning, freeze).
• Brittle bark + no leaves = dead tissue.

Surgical Pruning Protocol

1. Scratch test: Fingernail on bark. Green = live. Brown = dead.
2. Find transition zone: Where brown meets green.
3. Cut 1–2 inches into green wood with sharp, clean tools.
4. Remove all dead material.
5. Dry weather only. Disinfect tools between cuts if disease suspected.

Post-Pruning Care

• Water deeply during establishment.
• Mulch 3 inches (off trunks).
• Monitor for regrowth from cut points.
• If dieback recurs, investigate root/crown pathogens (Phytophthora, etc.).

African sumac is tough. Surgical removal of dead crown often stimulates vigorous, well-formed regrowth.