I have a Stihl KM 110 Kombi-motor with the little 12" chain saw on a 4ft shaft attachment. I like it for cutting off limbs close to the ground.

We limbed up 20 acres of pine and spruce for a fuel-break project at work. The guys really preferred the lightweigt aluminum Stihl pole saws with the curved saw blade instead of the powered blades for working up high. Keep WD-40 on the blade, have an extra sharp saw blade and find a good saw shop that can sharpen and set hand saws.

For stuff that resprouts at the ground, use a cut-stump herbicide treatment with concentrated Roundup or Garlon 4 and diesel fuel to the stump.