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
2023-08-10
71
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/2914495.html
相关试题推荐
ToliveintheUnitedStatestodayistogainanappreciationforDahrendorf
[originaltext]Whenwethinkofgames,thereareallkindsofthings.Maybeyou’
[originaltext]MyfellowSingaporeans:Whatwereyourmostmemorablemoments
[originaltext]MyfellowSingaporeans:Whatwereyourmostmemorablemoments
[originaltext]MyfellowSingaporeans:Whatwereyourmostmemorablemoments
[originaltext]AbeetleinvasionintheUnitedStateshaskilledatleasttwenty
[originaltext]AbeetleinvasionintheUnitedStateshaskilledatleasttwenty
[originaltext][12]Intoday’spersonalitystakes,nothingismorehighlyvalued
[originaltext][12]Intoday’spersonalitystakes,nothingismorehighlyvalued
[originaltext]Pianosarenormallyfoundinbuildingforobviousreasons.Howeve
随机试题
"Cool"isawordwithmanymeanings.Itstraditionalmeaningisusedto【C1】_
TheUnitedStatesisoftenconsideredayoungnation,butinfactitisnext
America’sFederalReservecutinterestratesbyanotherquarter-point,to3.
VideoconferencingisnothingmorethanatelevisionsetorPCmonitorwitha
[originaltext]M:Hello,Ihaveareservationfortonight.W:Yourname,please.
计算机执行指令的过程中,需要由()产生每条指令的操作信号并将信号送往相应的部件
脚手板搭接铺设时,接头必须支在横向水平杆上,搭接长度应大于()mm。A.200
在对某一类高层商业综合体进行检查时,查阅资料得知,该楼地上共6层,每层划分为12
我国人民代表大会制度的政治基础、根本原则和核心内容是()。A.民主集中制 B.
依最高人民法院《关于审理信用证纠纷案件若干问题的规定》,下列关于我国在信用证项下
最新回复
(
0
)