There are two types of secateurs, also called pruners; bypass and anvil. If you are using an anvil pruner for most of your pruning needs – you are using the wrong tool.
Anvil or Bypass Pruners
Anvil pruners work similar to a knife where a blade is pushed through the plant material onto a cutting board, ie the anvil. Bypass pruners work more like scissors where two blades pass by each other. At first glance there does not seem to be much of a difference between these tools, but the difference is significant. Anvil prumers tend to crush soft plant tissue. When you use a bypass pruner correctly (see below), you will do almost no damage to the plant.
Anvil pruners do work a bit better than bypass pruners for cutting up old dead wood but for most of us, that is not a very common job in the garden. You are usually pruning live plant material or wood that has recently died.
Using Secateurs Correctly.
Think about cutting back a branch to a fresh bud.The diagram below shows the correct cut, which is just above a bud.
In order to make the cut this close to the bud, the pruner needs to be held very close to the bud. With the anvil pruner there is a risk that the bud or the tissue around the bud sits on the anvil and gets damaged during the cut. Using bypass pruners, you can hold the pruner so that none of it touches the bud during the cutting process.
The diagram below shows the proper way to hold the pruner to cut off a branch from the trunk. The right side of the diagram – the wrong cut – will result in a stub and the metal parts of the pruner will touch and damage the stub – neither is good for the plant.
The important point to understand is that the secateur should be held so that none of the metal part touches the wood or stem that will be left on the plant. This does mean that you might need to turn your hand depending on your relative position to the bud. If you follow this rule, you will have very little damage to the plant.
1) Photo Source: Centurion Prunners
2) Photo Source: Virginia Tech
3) Photo Source: University of Kentucky – Agriculture