help erasing certain shades..

[batmanwest]

im using photoshop cs5.1. So i have a picture of a horse standing in front of a field. I want to take that horse and put it into another photo, but when i crop the horse out, there's remnants of the green background still in gaps between his tail and such.

Is there a way to go about deleting the background without interfering with the tail? I've tried with the background eraser without much luck. please help

 

[Dataflow]

try adding to the parts that show green using other areas of the tail (clone)
after you have deleted the background.
but every image is different so without seeing the image that might not work

 

[Remote-Medic]

If it's only minor bleeding of colours, use the sponge tool to desaturate those areas. May help but as Data says, difficult to know what will work without seeing the image.