"-" clues typically indicate a continuation of an answer that starts somewhere else in the grid. CROWBAR means that each of the four bars in the grid represents the word CROW, so you get 13A OVERCROWDED, 8D DECROWNED, 26D ESCROWING, and 36A MICROWAVING.
I don't get 14A, 16D, 23A, 35D, and 38A.