Trees ideally should have a wide root base that tapers up into the trunk. A bulge or lack of proper taper often ruins the visual flow from the rootline to the apex of the tree and is called reverse taper.
In this case several root cuttings of Willow Leaf fig, Ficus salicaria, were bound togeter in about 2006 and fused together to form a larger trunk accomplishing in a shorter time than it woud take to grow the same diameter trunk in my plant room. Fusion was helped greatly by using a large container and allowing free growth of the tree.
The first shot is taken in 2009 when the fusion was successful but the fusion was not totally complete.
2009, with trunks partially fused
A picture of the tree in 2014 shows good fusion and a reverse taper with the roots and base of the tree appearing narrower at the left side of the base than a bit farther up the trunk.
2014 showing the left side of the base of the tree with weak rootage
Three roots were moved around from the left front and left back of the tree. Two of the three roots were fused to other roots at the base and a chisel was needed to separate them from the base, allowing the roots to be moved. One root at the back was just up-rooted and moved around to the left side.
The lowest root on the back was simply dug out and easily moved around to the front
Side root is fused to the base – it is separated with a chisel
2015, the moved roots now enhance the base of the tree and eliminate the reverse taper