Chaucer compares the Squire to different things in nature. What are they?
Chaucer compares the Squire to various "soft" things in nature. He compares the Squire to things like flowers and birds. The birds are not raptors or anything like that. Instead, they are songbirds.
Chaucer compares the Squire to a meadow with lots of flowers in it. He says
Embroidered was he, like a meadow bed
All full of freshest flowers, white and red.
Chaucer then goes on to describe the Squire by making references to birds. He says that the Squire would sing all day long and then compares him to a nightingale.
By comparing him to these things, Chaucer is emphasizing the Squire's beauty and his interest in love. He spends more time talking about the Squire's looks and his interest in women (one reason he's like a nightingale is because he loved "so hot" that he didn't get any sleep at night) than he does talking about the Squire's military attributes.