Question
Hello Jim,
     I want to plant an Orange tree on my side yard in the grass next to my house.  Will the roots disrupt my house or come up to the grass?  My dirt is horrible clay.  I have already dug a hole approx.  4 ft deep and 4 ft wide.  I plan to fill the hole will some really good dirt.  

Answer
This is not a large tree and therefore the root system you will have not problem with the roots. It was very smart to dig the large hole this will allow the roots to spread and form a good system. I would mulch around the tree with not more than 3 inches of mulch this will help hold moisture and protect the tree from damage when mowing.