The speaker in Birches compares the boys climbing to

swinging birch trees.

The speaker in "Birches" by Robert Frost compares the boys climbing to swinging on birch trees.

To find out who the speaker in Robert Frost's poem "Birches" compares the boys climbing to, you can analyze the poem's text and literary devices. Here's how you can do it:

1. Read the poem: Start by reading the entire poem "Birches" by Robert Frost. You can find the text online or in a poetry collection.

2. Identify the section: Look for the specific section where the comparison is mentioned. In "Birches," there are several instances where the speaker talks about boys climbing birch trees. Scan the poem for the lines that refer to this imagery.

3. Analyze the comparison: Once you've found the section, examine the poetic language and devices used by the speaker. Consider metaphors, similes, or other figures of speech that Frost utilizes to convey the idea.

4. Consider the context: Reflect on the overall theme and tone of the poem to gain a deeper understanding of the comparison. Think about the speaker's perspective, emotions, and the message they're trying to convey.

By following these steps, you will be able to comprehend the poem and identify the comparison being made by the speaker.