Richard L. Parish | 11/25/2004 1:23:55 AM
Pruning shears are an important tool for most homeowners and grounds maintenance professionals.
They are useful for pruning trees and shrubs and for harvesting fruits, vegetables and flowers. Pruning shears come in two basic styles and in a wide range of sizes and price ranges.
Types of Pruning Shears
There are two common types of pruning shears: bypass and anvil. Bypass shears have two curved blades that slide past each other like a pair of scissors (Figure 1). One blade is usually thick, with a mildly tapered edge; the other blade is thinner and sharpened. Anvil shears have one flat blade (anvil) and a second, straight-edged sharp blade that closes against the anvil (Figure 2). It is sometimes assumed that a bypass pruner can make a neater cut, with less crushing and tearing of the wood, but testing has shown that bypass pruners will actually crush the branch more than a sharp anvil pruner. Most professional pruning shears are the bypass type; homeowner shears are available in both types.
Force Required to Cut
There are significant differences in force requirements to operate different shears. A test was conducted by LSU AgCenter personnel to evaluate the cutting force required by several pruning shears in cutting hardwood dowels. Neither the anvil nor bypass type has a clear advantage, but shears with Teflon-coated blades generally required less force.
Some of the anvil shears have a linkage that causes the blade to slide relative to the anvil while closing. This sawing action contributes to a lower force requirement when compared with anvil pruners that just close without the sliding action. Some pruning shears incorporate a ratchet action such that multiple strokes are needed to cut a large branch, but the required force is less with the ratchet action.
The cost of pruning shears can vary from $10 or less to more than $50. The higher-priced shears are generally built stronger and may use better materials such as stainless steel. Some inexpensive shears have plastic handles and are prone to breakage. The higher-priced shears are designed for professional use. Price is not a valid indicator of force required to cut; some of the less expensive shears do an excellent job of cutting with minimal effort.
Some of the shears will have Teflon-coated blades for corrosion resistance and reduced cutting effort. Testing has shown that the Teflon does indeed reduce the force required to make a cut.
Cleaning the shear after use will prolong the life of the tool. A solvent may be needed to remove sap from the blades. Avoid cutting anything except branches if you want to keep your blades in good condition. A pruning shear is not a wire cutter. Oiling the blade after cleaning will help prevent rust. The cutting blade should be sharpened as needed.
In summary, an anvil pruning shear with a sliding blade is probably the best all-around shear for a homeowner. They are inexpensive and have low cutting effort. A small bypass shear is better for flowers and very light pruning. Most professionals use higher-priced bypass pruners; the professional bypass shears may last longer, but don’t necessarily cut easier or cleaner. Ratchet-type anvil pruners are a good choice for cutting large branches (more than ½ inch in diameter).