Job 40:15
"Behold now behemoth, which I made with thee; he eateth grass as an ox."
Cross References (ranked by relevance)
Psalm 104:14
He causeth the grass to grow for the cattle, and herb for the service of man: that he may bring forth food out of the earth;
Job 40:20
Surely the mountains bring him forth food, where all the beasts of the field play.
Job 39:8
The range of the mountains is his pasture, and he searcheth after every green thing.