Pine trees can get up to heights of 50 to 100 feet depending on the type you have. If you like pine trees but prefer that they remain shorter and more manageable, you can do something about it as long as you don't mind maintaining the tree at its stunted height.
Allow the tree to get to the height you want, then climb a ladder to get near the top. Set the ladder so that it is on a stable surface with both legs.firmly on the ground; you do not want the ladder to wobble while you are on it. The upper part of the ladder should be placed against the tree so that the sides of the ladder straddle the trunk to keep it from slipping.
Cut the top stem, called the central leader, out of the tree with a tree trimmer or loppers when it is at your preferred height. Cut down 6 to 12 inches at an 45-degree angle. Loppers and shears are used when you can reach the branches or top of the tree from the ground, while tree trimmers, also known as pole saws, are used for branches anywhere from 6 to 20 feet off the ground. If working with a tree tall enough to require a ladder to trim the top, take precautions while up on the ladder. Have someone help you by holding the ladder for safety.
Cut the limbs below the top that you just cut. Trim them back several inches. Work your way down the sides of the tree, after finishing the top. Cut all branches back several inches to keep it in proportion, so that it still has the basic cone shape of a pine tree. Select one of the top small stems, just below the top stem that you cut short, and bend it upward. Use twine to tie it to the base of the central limb that you clipped. Wrap the twine around the stem that you bent upward, and then around the stub of the cut off stem. Tie the twine in a basic knot to secure it. This will give the tree a new central leader so that it doesn't form a fork.
Trim the tree every year or two to take off any new growth. A pine tree can grow a fork at the spot where you cut it even though you did try to form a new central leader. You must also use loppers to trim the sides of the tree because the sides will keep growing outward as well. This must be done each year to maintain the height and size. Loppers are placed just above a notch on the limbs where other stems, branches or pine cones are growing. Angle the loppers slightly, and make the cut by pressing the handles together similarly to scissors. Trim the branches back several inches.
Spray a sucker stopper to the top of the tree where you trimmed the leader. This product uses the chemical naphthaleneacetate and comes in a spray bottle. This is meant to stop sucker growth from growing back, but might work on the upper part to keep new growth from developing at the spot where you topped the tree. If all else fails, you will need to continue to cut the top out of the tree each year.