Sentence:  And as in winter, when the frost breaks up, / At winter's end, before the spring begins, / And a warm west wind blows, and thaw sets in— / After an hour a dripping sound is heard / In all the forests, and the soft-strewn snow / Under the trees is <WSD>dibbled</WSD> thick with holes, / And from the boughs the snowloads shuffle down; ... 
Meaning of the word marked with <WSD> tags:  To make holes or plant seeds using, or as if using, a dibble.