Tea Scale
Fiorinia theaeGreen, Diaspididae, HEMIPTERA


DESCRIPTION

Adult -The female tea scale is at first thin and light yellow, later becoming hard and brown. Elongate oval or boat shaped, it is 1.5 mm long, with the residue from the first molt attached at one end. The male adult is soft, white, and narrow with a ridge down the middle of its back (Color Plate 4FF).

Egg-The egg is yellow and lemon shaped.

Nymph-The nymph is a flat, yellow "crawler.".


BIOLOGY

Distribution -The tea scale has been reported on camellias in the South and in California.

Host Plants -In the Southeast, the tea scale is a serious pest of camellias as well as Chinese and Japanese hollies. It has also been reported on bottlebrush, dogwood, euonymus, ferns, mango, Satsuma orange, orchids, tea plant, and yaupon.

Damage -The infestation occurs primarily on the undersides of leaves. The most conspicuous characteristic of an infested plant is yellow splotching on the upper leaf surfaces, an effect of feeding insects underneath (Color Plate 4GG). The whole plant may appear generally unhealthy, with leaves dropping prematurely. The number of blooms decreases, and cuttings may die before roots develop.

Life History -Each female deposits from 10 to 15 eggs under the scale shell. They hatch in 7 to 21 days, depending on the weather. The flat, yellow crawlers migrate to the newer growth on the plant and, in 2 or 3 days, attach themselves. At first they secrete thin, white coverings, but shortly afterward they produce great quantities of white threads. When the population of nymphs is dense, the undersides of the leaves may be covered with this cottony secretion. The nymphs molt 18 to 36 days after hatching, and a second molting occurs about a week later. From 41 to 65 days after hatching, female scales begin to lay eggs. The life cycle is usually completed in 60 to 70 days. The hatching of tea scale nymphs occurs throughout the year, although it is less frequent in cold than in warm weather. Because there are many overlapping broods, crawlers can hatch continuously from March to November.


CONTROL

Several spray mixtures are recommended for the control of tea scale. These sprays should be heavily applied to the undersides of leaves. The best time to spray is in the spring, after the plants have finished blooming and the danger of cold weather has passed. Two applications, 10 days apart, should be sufficient. For specific chemical controls, see the current state extension service recommendations.

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