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
2024-03-13
61
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、Collect ash tree seeds for experiment.
B、Preserve the healthy ash tree seeds.
C、Set up a new seed bank for research.
D、Develop a new breed of ash tree.
答案
B
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3530758.html
相关试题推荐
[originaltext]Whenwethinkofgames,thereareallkindsofthings.Maybeyou’
[originaltext]AbeetleinvasionintheUnitedStateshaskilledatleasttwenty
[originaltext]AbeetleinvasionintheUnitedStateshaskilledatleasttwenty
[originaltext]AbeetleinvasionintheUnitedStateshaskilledatleasttwenty
[originaltext]Overthepastdecade,theenvironmentalmovementhasexplodedont
[originaltext]Overthepastdecade,theenvironmentalmovementhasexplodedont
[originaltext]Overthepastdecade,theenvironmentalmovementhasexplodedont
[originaltext]Hello,I’mCallumRobertsonandyou’relisteningtothemusicsho
[originaltext]Hello,I’mCallumRobertsonandyou’relisteningtothemusicsho
[originaltext]Hello,I’mCallumRobertsonandyou’relisteningtothemusicsho
随机试题
Wherearetheytalking?[br][originaltext]M:HowlongcanIkeepthisbook?W
Sinceancienttimesvolcanoeshavestruckterrorandwonderintothehearto
影响气道阻力最重要的因素是:A.呼吸道长度 B.气流速度 C.气流形式 D
水害监测预报系统技术主要包括( )。A.煤矿水害监测预警系统 B.基本水文地
下列自治区中最早建立的是()。A.西藏 B.内蒙古 C.宁夏 D.新疆
各种运输方式内外部的各个方面的构成和联系,就是( )。 A.运输系统
量化交易主要指通过数学分析、挖掘价格运动规律,对相关宏观经济指标、财务数据、量价
甲乙丙三国订有贸易条约。后甲乙两国又达成了新的贸易条约,其中许多规定与三国前述条
银行承兑汇票的承兑银行,应当按照票面金额向出票人收取()的手续费。A:千分之一
影响能量代谢最主要的因素是A.寒冷 B.高温 C.肌肉活动 D.精神活动
最新回复
(
0
)