Sentence:  Bloodroot in the leafless wood, Companion of gray Solitude, When the birds begin to sing, Thou, frail <WSD>welcomer</WSD> of Spring, Dost thy whitcray'd star unfold, With its seedheart of green'gold, And remindest us how Faith Blooms victorious over Death. 
Meaning of the word marked with <WSD> tags:  Something or someone that greets or is present for the arrival of something.