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
43
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/2914771.html
相关试题推荐
[originaltext]I’vementionedhowDNAhassolvedmanymysteriesinbiology.And
[originaltext]I’vementionedhowDNAhassolvedmanymysteriesinbiology.And
[originaltext]I’dliketolookatavitalaspectofe-commerce,andthatisthe
[originaltext][13]Americansaresufferingfromaserioussleepdeficitasthey
[originaltext][13]Americansaresufferingfromaserioussleepdeficitasthey
[originaltext]Andnow,ifyou’llwalkthisway,[9-1]ladiesandgentlemen,the
[originaltext]Andnow,ifyou’llwalkthisway,[9-1]ladiesandgentlemen,the
[originaltext]Andnow,ifyou’llwalkthisway,[9-1]ladiesandgentlemen,the
[originaltext]M:Ireallydon’tknowwhattodothissummer.[5]Ican’tafford
[originaltext]M:Ireallydon’tknowwhattodothissummer.[5]Ican’tafford
随机试题
Iamdelightedtobewithyou.IfirstvisitedChina22yearsago,butthis
Apaper,Anatomy(剖析)ofaLargeScaleSocialSearchEngine,layingoutast
Whatistherelationshipbetweenthespeakers?[originaltext]M:Hi,Sue.Whereh
FireswerecommoninLondoninthe17thcentury.Mostbuildingsweremadefromw
Universitiesacrossthenationhavedecidedtodomorethantalkabouttherise
A
致完欢送词,地陪将“旅游服务质量评价意见卡”发给游客填写,如果游客带回家填写,地
服务对象:“我要是考不上研究生,我妈妈会非常不高兴,那真可怕!” 社会工作者:
(2018年真题)甲公司为增值税一般纳税人,2018年发生的有关交易性金融资产业
25岁初孕妇,停经18周,不觉胎动。产科检查。宫底高度在脐耻之间,胎方位及胎心不
最新回复
(
0
)