The American grey squirrel, introduced to the United Kingdom, not only out-competes the native red squirrel — an impact hard to value in monetary terms — but damages coniferous trees and reduces their value as timber.The cost in terms of damage and control of invasive alien species in the United States has been estimated at EUR 80 billion each year.
Meastar go bhfuil an costas i dtéarmaí damáiste agus rialú speiceas coimhthíoch ionrach sna Stáit Aontaithe cothrom le EUR 80 billiún gach bliain.