首页
登录
职称英语
[originaltext]A beetle invasion in the United States has killed at least twenty
[originaltext]A beetle invasion in the United States has killed at least twenty
游客
2023-08-13
19
管理
问题
A beetle invasion in the United States has killed at least twenty million ash trees. The invasion of the emerald ash borer was first discovered near Detroit, Michigan, in 2002. Experts believe the small green insects arrived in the 1990’s in shipments of goods from China.
[16] The emerald ash borer has destroyed trees in the Midwest and as far East in the United States as Maryland. [17] The insects have also spread as far north as Ontario, Canada.
Ash trees can resist many diseases. But they cannot resist the emerald ash borer. [18-1] It lays eggs on the bark.The young larva drill into and feed on the inner bark. This harms the ability of the tree to transport water and nutrition.
In some places, farmers are using “detection trees”. They have an area where bark has been cut away. The area circles the tree. [18-2] The process weakens the tree. It makes them easier targets for borers, and shows if the insects are nearby.
Efforts to stop the spread of the emerald ash borer include cutting down affected trees. There are worries that the ash tree might disappear unless the invasion is controlled. To prepare for such a possibility, a government laboratory is asking people to send in the seeds from ash trees. [19] It examines and X-rays the seeds to make sure there are no living borer fertilized eggs.Only the best seeds are remained and then sent for storage in a seed bank. There, they are dried and frozen. Should the seeds ever be needed, the hope is that scientists might someday develop an ash tree that could resist the little green attackers.
1.What’s the speaker mainly talking about?
2.How far do the insects spread northward?
3.Why is part of the bark cut away?
4.What is the government laboratory trying to do?
选项
A、Shipments of goods from China.
B、Detection trees.
C、The seeds from ash trees.
D、The invasion of the emerald ash borer.
答案
D
解析
转载请注明原文地址:https://tihaiku.com/zcyy/2923636.html
相关试题推荐
[originaltext]TodayI’dliketotalkaboutthesculptorHenryMoore,inpa
[originaltext]TodayI’dliketotalkaboutthesculptorHenryMoore,inpa
[originaltext]Let’sbegintodaybydiscussingenzymes.Enzymesarewhatma
[originaltext]Let’sbegintodaybydiscussingenzymes.Enzymesarewhatma
[originaltext]Let’sbegintodaybydiscussingenzymes.Enzymesarewhatma
[originaltext]TheEducationSelectCommitteehasbeenexaminingtheunderac
[originaltext]TheEducationSelectCommitteehasbeenexaminingtheunderac
[originaltext]TheEducationSelectCommitteehasbeenexaminingtheunderac
[originaltext]M:Goodmorning.Doctor.W:Goodmorning,Mr.White.WhatcanId
[originaltext]M:Goodmorning.Doctor.W:Goodmorning,Mr.White.WhatcanId
随机试题
TheAdvantagesandDisadvantagesofBuyingLottery
A、Theyweremainlyonherleftleg.B、Theyweremainlyonherrightleg.C、They
某服装加工厂需生产1600件上衣,所有上衣如果由甲、乙、丙车间合作生产,完成任务
尾矿库建设的勘察、设计、安全评价、施工及施工监理等工作必须由具有相应()条件的
A.发热和盗汗 B.腹水 C.肠瘘 D.腹部肿块 E.肠梗阻粘连型腹膜炎
心搏骤停患者对缺氧最敏感的组织是A.大脑 B.肝脏 C.心脏 D.肾脏
关于普通股票和优先股票的说法错误的是()。A.普通股票的股利完全随公司盈利的高
Thechangeinthatvillagewasmiraculou
关于皮肤黏膜淋巴结综合征患儿急性期的护理措施不妥的是A.注意休息,适当活动 B
中间商的购买决策主要包括( )。 A.消费水平决策 B.供货监督决策
最新回复
(
0
)