Physical & Mechanical Fruit Injury

 

Stem Puncture: This is where a stem or twig end has punctured the skin of an adjacent fruit, fairly recently. Usually the causal projection is obvious when the fruit is still on the tree.

 

Rub: This is usually a smooth brownish spot on the skin from repeated rubbing against a branch.

Scratch: This is usually a series of parallel grainy lines on the fruit surface, where something long ago scratched hard enough to injure the skin, probably during wind or other movement.

Bruise: This is an indented injury, but the skin is intact. It looks like it was caused by something large hitting the fruit (or vise versa). Farm machinery can cause some of this, for fruit hanging in the drive rows, especially in tight blocks.

 

Hail: Hail injury takes on different forms, depending on how hard the strikes were, and how much time has elapsed since the injury. Sometimes it can be confused with curculio injury or tarnished plant bug injury. It can appear as a series of dents in the fruit (unbroken skin), or a series of grainy healed-over marks. Lower surfaces of the fruit (at the time of the storm) are not affected; this is a clue to identity. Occasionally the injury heals as outward surface bumps. Rotary mowers occasionally propel twigs or pebbles into fruit, and cause identical injury.