Why wont my dog stop taring up the dirt and grass?

We just move in and this is his first time experiencing having a backyard to play in. I have an almost 2 year old american cocker spaniel. He continues to dig holes everywhere and chews up the the grass. I don't think he wants to really eat it though because he spits it out. He just tares up the grass! Is there anything i can do to stop this?