There are many different images in the poem "The Sun is Blue" by Richard Aitson.
Imagery (or the images depicted in the poem) is used by an author to evoke the any, or all, of the five senses (sight, sound, taste, touch, and smell). This poem elicits many of the senses.
First, "my voice is dust", and later, "my mouth is dry"-Readers know what it is like for their mouths to be so dry that it feels like dust. This appeals to the sense of taste.
Next, "a word caught between my teeth" refers to the sense of taste and sound. Many people know what it is like to be unable to speak. A word caught in their throat (or here their teeth). readers also know what it is like to have something caught in their mouth (think "it leaves a bitter taste in my mouth").
"Eagles and hawks make me listen to chants" evokes the sense of sound. Readers have heard birds call out. We can recognize the idea of birds chanting because we have heard this sound before.
There are many references to sight: "old wrinkled meat women", "children without homes", "horses without riders", and "blood".
Imagery is designed to draw readers into a poem. Readers may not need to know the area described, the time period, or the ethnicity of the author. All it takes is the ability of an author to evoke the senses of a reader and the reader can then relate and interpret a poem.