The following specific defects, or any combination of them when the combined seriousness exceeds the maximum allowed for any one defect, are considered injury to winter pears.

(1) Russeting: On any winter pear varieties, any amount of characteristic russeting is permitted, whether caused by natural or by artificial means. Leaf whips or light limb rubs that resemble and blend into russet areas are considered russet.

(a) Slightly rough russeting or thick russeting characteristic of frost injury is considered injury when the aggregate area exceeds one-half inch in diameter on Comice, Anjou, and other smooth-skinned varieties.

(b) Smooth solid russeting is considered injury when the aggregate area exceeds one-half inch in diameter on Anjou or other smooth-skinned varieties or when smooth netlike russeting exceeds fifteen percent of the pear's surface.

(c) Smooth solid or smooth netlike russeting is considered injury when the aggregate area exceeds one-third of the surface on Comice pears. On Anjou, Comice, and other smooth-skinned varieties, any amount of characteristic smooth russeting is permitted on the portion of the calyx end that is invisible for more than one-half inch along the contour of the pear when the pear is placed calyx end down on a flat surface.

(d) Rough or thick russeting, none allowed, except russeting characteristic of frost injury is considered damage when the aggregate area exceeds one-half inch in diameter for Bosc, Seckel, and other similar varieties.

(2) Limb rubs are considered injury when they are cracked or softened or more than very slightly depressed or not light in color or exceed an aggregate area of three-fourths inch in diameter.

(3) Hail marks or other similar depressions or scars are considered injury when they are not very shallow or superficial or when they affect an aggregate area of more than one-fourth inch in diameter.

(4) Cork spots are considered injury when a pear shows depressions or other external evidence of the disease.

(5) Sunburn or sprayburn is considered injury when the normal color of the pear has been materially changed or the skin is blistered or cracked or the flesh is softened or discolored.

(6) Insect stings are considered injury when there are more than two healed slight stings or depressions or the stings materially affect the general appearance of a pear.

(7) Blister mite or canker worm injury is considered injury when it is not shallow and superficial or when it affects an aggregate area of more than one-fourth inch in diameter.