From Barn Yard to Growing on a Green Yard by JLD (Horticulturist, AS)

To use manure/straw over grass I would first find out what kind of grass it is. If it is a spreading or crawling grass like Bermuda,st Agustin ,or ki ku yu,etc. I would recommend covering it with thick layer of cardboard first and then add straw (mulch), not planting in it until next spring. If the grass is blue grass , rye ,fescue etc type just throw straw on  16 inches or more. Since the straw has urine and manure in it, it will be too hot to plant directly into it. What I would do is make planting holes by pushing straw away and forming pits in it. I would then fill with good top soil or planting mix and plant vegetables, and annuals. For planting trees I would push the straw away until you reach the grass, dig the hole, plant the tree with soil, and then cover with straw staying 12  inches away from trunk.

LAYER ONLY AGED STRAW

It is always good idea to age the straw bedding a year before using it for layering. Then it  will not be a problem.

Problem: When ever mixing mulch or soil together it may cause a lack of nitrogen.