What are some examples of ways in which Crooks was treated as inferior in chapter 4?

Crooks, a black man, is treated as an inferior in many ways. First, he does not sleep in the bunkhouse with the other men but is isolated in a little shed off the barn, as if he is an animal. As further evidence he is treated like an inferior, his "bunk" is a box of straw with blankets thrown over it. A manure pile is kept under his window
Showing that he is segregated against his will, Crooks explains to Lennie that he lives by himself because he isn't wanted in the bunk house. Crooks says the other hands won't play cards with him there because he's black. They also tell him that he stinks.
Finally, when Crooks tells Curley's wife to leave his room, she turns on him in a way she doesn't dare to turn on Candy, knowing she can get away with it with Crooks because he's black. She says to him:

"Well, you keep your place then, Nigger . . . I could get you strung upon a tree so easy it ain’t even funny."