New diet?

This weekend we went to Moses Lake for Jonny's baptism. We had a nice trip and beautiful weather. On Saturday we went to watch both Abby and Jonny play soccer. While we were at Jonny's game, Colin started eating grass. He tried multiple varieties...brown dried out grass and green grass. He liked both. I just hope it didn't have fertilizer on it. ) What would make a child like grass? Later, he asked for a piece of gum and within seconds he returned the barely chewed gum to me, but my mom later told me she found him chewing the wrapper. I have also found him eating kleenex and paper. The strange thing is I can't get him to eat anything good like chicken, pasta, cheese, vegetables, etc. This morning when he was eating his cereal, he didn't want to finish it and he said he wanted grass. I told him his cereal was grass and he finished it. I have heard kids will eat what their bodies need...what in the world does grass, gum wrappers, and kleenex provide?