What is a walnut cross ditch elephant?

Scientific name: Walnut Worm. Also known as walnut root weevil and walnut yellow spot weevil. Coleoptera, weevil. The adult is 1 1 ~ 16 mm long and 6 ~ 7 mm wide. The body is black and dull; At the front end 1/3 of each COLEOPTERA, from the outer edge to the fifth line and the wing slope, yellow-brown hairy scales form a row of narrow bands, and there is a pinch of scales behind the wing tumor and the midfoot internode protrusion. Most or all scales on the outer edge and ventral surface of beak, foot and COLEOPTERA are white. The antenna of female insect is located at the front end of beak 1/4, and that of male insect is located at the front end of beak 1/6 (see figure). China, Sichuan, Shaanxi, Shanxi, Henan, Hebei and Fujian. Harm the phloem of walnut root neck. Two years 1 generation, overwintering as adults and larvae. Overwintering adults began to move in late March of the following year. At the beginning of April, they went to the tree to feed on leaves and fruits and supplement nutrition. Come down from the tree in mid-June and scatter the eggs in the skin seam 3 ~ 10 mm deep in the root neck. When the young larvae overwinter at the end of the wormway, the second old larvae overwinter. In the third year, the overwintering mature larvae pupated in May and began to emerge into adults in mid-June. The life span of adults is 430 ~ 464 days. Each female lays 59.5 eggs on average, and the maximum is 1 1 1 egg. The egg period is 7 ~ 1 1 day, with an average of 8 days. The larval stage is 20 ~ 22 months. Pupal period 17 ~ 29 days, with an average of 25 days. Control methods: seal lime mud on the root neck to prevent adults from laying eggs; In winter, combined with the recovery of tree discs, turn up the root neck soil and kill the larvae; From April to June, dig up the root neck soil, spray 50% acetaminophen EC or 90% trichlorfon 200 times solution, or fill the rhizosphere with liquid medicine, and then cover the soil; 74 1 intubation aerosol was used in adults.

Sequoia forest in California, USA

Ding Keren contributed

Sequoia sequoia in California, USA

Selected from Forestry Illustrated

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Wang suddenly said

29 Radiation pine forests in New Zealand

Suyunshan

Spruce forest in Sweden

Shen xihuan

3 1 draw Berlin, Japan

Suyunshan

32 forests of the Soviet Union

Selected from "Soviet Forest"

Picea forest in the Federal Republic of Germany

From the Bavarian forest

34 yuehua dwarf forest

Wayne Wang

35. Korean pine broad-leaved forest

Shen Xiaohui

Schematic diagram of world forest area

37 coniferous forest

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Gao Changfu

37 coniferous forest

Pinus sylvestris forest

Li Fuzhu

37 coniferous forest

Liushanlin

Ding Keren

Walnut weevil adult