There are some ways to speed this all up. I don't know what version of PS you have, but if it is CS, CS1 or CS2 or CS3 there is a tool called the Patch tool (part of the healing brush package), and it can do wonders. Here is an example that tool about 90 seconds. I'm showing illustration 1, which was the longest which was to make a rough selection with the Polygon lasso tool or you can use the patch tool to make the selection which gets us to
Then using the patch tool drag the selection to the right in this case as seen in this next screen shot
Watch carefully the original selection as you'll see what is being replaced in it as you drag right. As soon as I got to where you see above, I released the mouse button and the first patch was made. Then I drug the same selection again to get the rest of the trash can (again dragging the selection right). You just have to experiment with the patch tool a little to see how powerful it is.
Here is what I ended up with at the end of 90 seconds
Now you can use the clone tool or the patch tool again to clean up little areas.
Even though this was a quick and dirty and hasn't been cleaned up yet, it shows the principle. It also leaves the shadow of the tree which your's doesn't. You would then play a bit with the patch tool to get rid of the shadow of the trash can.
Cheers,
rfs