In apples, which size indicates "appreciable damage" due to limb rub?

In the context of apple grading, the term "appreciable damage" due to limb rub refers to visible injury on the surface of the fruit that impacts its quality. For apple sizing, a measurement of 3/4" signifies the threshold where such damage begins to be significant enough to affect the fruit's marketability.

At this size, the limb rub can cause noticeable blemishes that might lead to a deduction in quality grade. As fruit sizes grow larger, the expectations for surface quality also enhance. Hence, a 1/2" apple may not display sufficiently pronounced damage to warrant the label "appreciable," while 1" and 1 1/4" apples likely entail even more pronounced damage, rendering them unsuitable for higher grades.

Thus, 3/4" serves as the critical point in determining whether the extent of limb rub damage is beyond what is acceptable for high-quality apples.