Clippers may be used for collecting bud sticks or shortening stock material. Because they may crush as well as cut, they are not usually used to cut surfaces which will be involved in callus formation and cambial connection. However, in some cases, such as top wedge grafting , a pair of bypass clippers may be used to cut the stock. In such cases, it is best to use bypass clippers, not anvil clippers.
Anvil blades are even more likely to crush the cut end.
Some grafters like it because it is black, and provides heat to aid callus formation . However, in some climates and situations, such as spring in the Pacific Northwest, it absorbs too much heat. It shares the disadvantages of Polyethylene strips in that it doesn't degrade and can cause girdling. They range in size from a blade a few inches long to something resembling a machete, which is used for making cleft grafts in thick trunk or branches. Most grafting knives are similar in size and shape to a paring knife.