Are the sod crops the same as cover crops?

Not quite. Sod crops are grass crops grown for their root mass and/or their landscaping appeal. Cover crops are grasses and broadleaves, some of which are legumes, grown for their various abilities to shield soil from erosion, add organic matter to soil, build soil tilth, and add soil nitrogen. Sod crops are usually removed from the field, while cover crops are either tilled into the soil or left on top to decompose.