TL;DR
Crown thinning is the selective removal of interior and crossing branches throughout a tree's canopy to reduce its density without changing its overall size or silhouette. The goals are better light penetration to lawns below, lower wind sail in storm-prone areas, and removal of rubbing or poorly attached limbs; ANSI A300 guidance caps live-tissue removal around 25 percent per cycle.
What it means
Crown thinning is the selective removal of interior and crossing branches throughout a tree's canopy to reduce its density without changing its overall size or silhouette. The goals are better light penetration to lawns below, lower wind sail in storm-prone areas, and removal of rubbing or poorly attached limbs; ANSI A300 guidance caps live-tissue removal around 25 percent per cycle. Over-thinning that leaves tufts of foliage only at branch tips, known as lion-tailing, weakens limbs, so the right result looks subtle, not dramatic.
Where it sits in the glossary
Crown thinning is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
ProFix tools that touch this term
See also
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