A gas pole saw, also called a gas tree pruner or a petrol tree pruner in the UK, is an improvement on manual pruning saws. A gas pole saw is useful on older trees and where there are many trees to be pruned on a property. It is also good for removing larger branches that are difficult to prune with a manual pruner or dangerous to prune with a standard chainsaw.
The cutting chain of a gas pole saw is at the end of a pole or rod. The operator holds a small gasoline engine at the base. Gas pole saws generally weigh from 13 to 18 lbs. Their poles are 8 to 12 feet long; some models have extensions that make them 14 or 15 feet. Some manufacturers sell gas weed trimmers with extensions that turn them into pole saws. Weed trimmers converted into pole saws are not as efficient as dedicated pole saws but they are useful for modest pruning chores.
An electric pole saw has more power than one operated by hand. A gas pole saw has more power than an electric model. Most models are powered by 2-stroke gasoline engines in the 25cc range. A 2-stroke engine means that the operator has to add oil to the gas. These small engines do not have the same power as standard chainsaws.
It is dangerous to climb up a tree with a chainsaw or operate a chainsaw from a ladder so larger limbs are often not pruned, giving trees a lopsided, unbalanced look. Gas pole saws make it possible to prune those limbs from the ground. A model that extends to 14 feet gives a pruning reach of about 20 feet including the height of the operator.
You should look for enough power to cut larger limbs; several models are available with 25cc, 2-stroke engines. The engine should be easy to start and the saw should be as light as possible. A long pole is desirable; there are several models on the market that are 12 feet long. The saw should have good balance when you hold it, and it should have soft grip handles. The chain should be oiled automatically.
Black & Decker, Craftsman, Echo, Husqvarna, Ryobi, Stihl and other manufacturers of small, gasoline operated tools also make and market gas pole saws. Troybilt and Poulan are among the makers that market gas weed eaters or trimmers with chainsaw attachments that turn them into pole saws.