Assessing Dieback in a Mature Walnut Tree with Trunk Splits

A possible walnut tree (trunk splits for years) had no leaves in spring, then sprouted new branches on 1/4 of the tree. 3/4 is bare/dead.

Possible walnut

Trunk splits

Significant dieback—likely due to internal decay entering through old trunk splits.
New sprouts are the tree's attempt to survive.
Trunk splits are entry points for decay fungi.

Wait until next spring to prune. Removing live wood now adds winter stress.
Scratch test: Gently scrape bark on questionable branches. Green = alive; brown = dead.
Next spring, remove only dead wood.
Monitor canopy density annually. If decline continues, plan for removal.

Large dead limbs over structures or walkways should be removed by a professional arborist sooner.

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