This pine has grown outward over the grass/yard about 5 feet - If I cut off the main branches that have grown from ground level out over the yard, the branches behind them would have very little needles. Late winter (now in Colorado) is the time to prune if my research is correct, so I need to decide to prune or just remove. My question is - will the branches begin to grow needles again after I remove the outer branches?
Pine pruning - will it produce new needles (greenery)?
On conifers, anything that has all the green removed will not regrow. The branches you describe sound like they shaded out and died, and should come off also. When christmas-tree farmers raise pines and firs for several years, they shear only the green and soft twigs - once a year, or a couple times a year, depending on the species. This gives them the bushy soft look you see on those trees. To keep one shaped the way you want it - start early in the tree's life, and cut any green-soft stuff to half length. This will make it bud-out along the remaining green-soft you've left. This way you can head it back from where you don't want it, and it'll get bushy along the area you trimmed. Any branch or stalk that's hard and has the green removed will die. This is why you can cut a conifer down at ground level, and have it not sucker from the stump.