The speaker in "Birches" compares the boy's climbing to D. Filing a cup to the top.
<em>"To the top branches, </em><em>climbing </em><em>carefully</em>
<em>With the same pains you use to</em><em> fill a cup</em>
<em>Up to the brim</em><em>, and even above the brim."</em>
Afterwards. the author uses the line <em>"like girls on hands and knees that throw their hair before them over their heads to dry in the sun"</em> to describe C. The shape of the trees after an ice storm.
<em>"</em><em>Loaded with ice</em><em> a sunny winter morning</em>
<em>After a rain</em><em>. [...]</em>
<em>Soon the sun's warmth makes them shed </em><em>crystal shells</em>
<em>Shattering and avalanching on the snow-crust— [...]</em>
<em>You may see their </em><em>trunks </em><em>arching in the woods</em>
<em>Years afterwards, trailing their leaves on the ground</em>
<em>Like girls on hands and knees that throw their hair</em>
<em>Before them over their heads to dry in the sun</em><em>."</em>