Sentence:  Next spring the owner of the hedge will be very much surprised to find a number of his <WSD>arbor vitae</WSD> deceased, and he will straightway blame himself and his horse? Not he! The nurseyman, sir, must have delivered him some poor stock! 
Meaning of the word marked with <WSD> tags:  Any of the evergreen trees and shrubs known as arborvitae, of the genera "Thuja" and "Thujopsis", or of the species (noshow=1).