Also known as camellia. It is one of the precious tree species in China. Small evergreen trees or shrubs. The crown is oval. The bark is smooth. The shoots are hairless. The leaves are oval, 7 ~ 10 cm long and 2.5 ~ 6 cm wide, with fine teeth on the edge, dark green luster at the top and green hairless at the bottom; Petiole 5 ~ 15 mm, glabrous. Flowers are large, terminal or axillary in pairs, with a diameter of 5 ~ 10 cm, bracts and sepals 9 ~ 10, 6 ~ 7 petals of wild species, light red at the base, filaments connected into short tubes: ovary 3-loculed, style 3-cleft. Capsule nearly spherical, 3 ~ 4 cm in diameter. China, Shandong, Zhejiang, Jiangxi and Sichuan. Japan and Korea are also distributed. As a precious ornamental tree species, its cultivated varieties are all over the world. It has been cultivated for 1000 years. At present, there are more than 15000 cultivated varieties with bright colors, such as crimson, white, pink and variegated colors, and most of them are double petals. The oil content of seeds is 45%, oil is edible and used in industry, and flowers are a astringent hemostatic agent. Strong resistance to sulfur dioxide and hydrogen sulfide. Suitable for warm and humid climate, deep and fertile acidic yellow soil (pH 4 ~ 5) and well-drained red soil. The flowering period is long, and February, March and April are all in full bloom.

White wheel shield scale of Sassafras sassafras (Peng Jianwen)

Scientific name: Aulacaspis sassafris Chen. Homoptera, Coleoptera. The female adult is 1.7 ~ 2.5 mm long, rod-shaped, purplish red, with degenerated antennae, missing feet and round and white shell (see figure). Male adults are 0.6 1mm long, spindle-shaped, orange-red, with long tentacles, white hair, 10 nodes, white and translucent wings, degenerated mouthparts, long and narrow mating apparatus and no tail silk in the abdomen. China, Hunan, Anhui and Jiangxi. Harm. It has three generations a year, and overwinters on branchlets with 2nd instar nymphs and male pupae. In late March, the female nymph developed into an adult, mated with the male insect that emerged in early April, and began to lay eggs in late April, with the peak of laying eggs in mid-May. The first generation nymphs hatch from late May to early June and develop into adults in late June. The second generation nymphs hatch in early July, develop into adults in early September, and the peak of spawning is in mid-September. The third generation nymph hatched in the middle and late October of 10/0, and overwintered on the twigs in the early February of 10. Male adults have weak flight ability, mainly crawling. Generally, females only mate 1 time, the first generation lays eggs 1 12 ~ 2 10, the second generation 32 ~ 144, and the third generation 12 ~ 43. The white-wheel shield scale of Sassafras sassafras mostly occurs in warm and humid forests, and the 6 ~ 10 young forest is the most harmful. It is distributed on stems, branches and leaves, and the density of branches and leaves at 1 ~ 2 years old is the highest. Natural enemies include ladybugs and lacewings. Prevention and control methods: protect natural enemies; Spraying dimethoate emulsion, dichlorvos emulsion and Nale EC in nymph stage.

Female adult of the white-wheel shield scale of Sassafras sassafras