Finished photograph

First pass cloned photograph

The next stage can not really be shown all that well.

Deselect the Lassoed area by SELECT, DESELECT or keyboard short-cut Ctrl + D

You will now have a very discernible area of grass where it is obvious that something has been tampered with. The trick is to soften the edges with more cloning, but do not continuously clone, do in in wee bits and resist the urge to drag the mouse, this only creates repeat patterns, which makes it dead obvious that the area has been cloned.

Finished clone

There are no sharp edges and the grass has been blended together.

The pattern has a very slight repeat but that can be a natural feature of the grass and at this level of zoom can easily be accepted as natural.