Desiring Fruit

Galatians 5:16-17 ESV

16 But I say, walk by the Spirit, and you will not gratify the desires of the flesh. 17 For the desires of the flesh are against the Spirit, and the desires of the Spirit are against the flesh, for these are opposed to each other,to keep you from doing the things you want to do.

We are shaped by our desire. 

Paul goes on to contrast the works of the flesh with the fruit of the Spirit.  Note the difference resulting from the two.  Implied is the idea that, left on our own, we are subject to the natural working of the flesh, with its predictable results.

If the Spirit is present, something else is possible where it was not before.  It is not a work of our doing, but a work of the Spirit.  Like a seed that is planted and comes up as we tend it, we are unaware of exactly how this happens, but give witness to the changes.  Fruit grows and appears on the attached branch.  It speaks more of an abiding than of works.
That said, faith without works is dead.  It is in works that the Spirit is "fleshed out" as it were, its presence made manifest.  This is the fruit which defines whether or not a branch is barren, and which needs pruning.