Serious damage means any injury or defect which seriously affects the appearance, or the edible or shipping quality.

(a) Russeting which in the aggregate exceeds the following shall be considered as serious damage:

(1) On all varieties, excessively rough russeting (russeting which shows “frogging” or slight cracking) when the aggregate area exceeds three-fourths inch in diameter.2

(2) On all varieties, thick russeting such as is characteristic of frost injury, 15 percent of the surface.

(b) Any one of the following defects or combination thereof, the seriousness of which exceeds the maximum allowed for any one defect, shall be considered as serious damage:

(1) Limbrubs which are more than slightly cracked, or excessively rough limbrubs or dark brown or black discoloration caused by limbrubs which exceeds an aggregate area of three-fourths inch in diameter. Other limbrubs which affect an aggregate area of more than one-tenth of the surface.2

(2) Hail marks or other similar depressions or scars which affect an aggregate area of more than three-fourths inch in diameter, or which materially deform or disfigure the fruit.2

(3) Drought spot when more than two in number, or where the external injury affects an aggregate area of more than three-fourths inch in diameter, or when the appearance of the flesh is seriously affected by corky tissue or brownish discoloration.2

(4) Sunburn or sprayburn where the skin is blistered, cracked or shows any brownish color, or where the shape of the pear is materially flattened, or the flesh is softened or materially changed in color, except that sprayburn of a russet character shall be considered under the definition of russeting.

(5) Insects: (i) Worm holes. More than three healed codling moth stings, of which not more than two may be over three thirty-seconds of an inch in diameter, or other insect stings affecting the appearance to an equal extent.2

(ii) Blister mite or canker worm injury which affects an aggregate area of more than three-fourths inch in diameter or which materially deforms or disfigures the fruit.2

(6) Disease: (i) Scab spots which are black and which cover an aggregate area of more than one-half inch in diameter, except that scab spots of a russet character shall be considered under the definition of russeting.2

(ii) Sooty blotch which is thinly scattered over more than 15 percent of the surface, or dark, heavily concentrated spots which affect an area of more than three-fourths inch in diameter.2