Scurfy scale

Taxonomic position. The scurfy scale (Chionaspis furfura) is a member of the order Hemiptera and the family Diaspididae. This pest is a common armored scale insect, characterized by its protective shield which is typically grayish-white and resembles a small comma in shape, making it distinct on tree bark.

Host plants. Scurfy scale predominantly infests a wide range of fruit-bearing trees, including apple, pear, plum, peach, and cherry. While less frequent, infestations can also occur on various ornamental shrubs and small fruit bushes found in or near home orchards and commercial plantations.

Biology and life cycle. This pest completes one generation per year. It overwinters as reddish-colored eggs beneath the female's protective scale. In the spring, after the bloom period, the crawlers hatch and emerge from under the cover. These small mobile nymphs move to new bark areas to feed, where they eventually settle, become stationary, and begin secreting their protective scale covers.

Damage and economic significance. The damage is caused by the nymphs and females extracting sap from the phloem of twigs, branches, and trunks. Heavy infestations lead to a decline in tree vigor, reduced growth, leaf yellowing, and eventually the death of smaller branches. The cumulative stress makes the trees more susceptible to environmental factors and disease.

Protection measures. Management programs combine cultural practices and chemical control. Physical removal by scrubbing bark or heavy pruning helps reduce populations. Chemical treatments are most effective during the crawler emergence phase, targeting the vulnerable stage before the hard shell forms. Dormant oil applications in late winter are also recommended to smother overwintering eggs.