AY Honors/Forestry/Answer Key
An increment borer is a specialized tool used to extract a section of wood tissue from a living tree with relatively minor injury to the tree.& The tool consists of a handle, an auger bit, and a small, half circular, metal tray (core extractor) that fits into the auger bit. The auger bit is usually manufactured from carbide steel. It is most often used by foresters, researchers, and scientists to determine the age of a tree. This science is also called dendrochronology. This enables the user to count the rings in the core sample to determine the age of the tree or the growth rate of the tree. After use the tool breaks down and the auger bit and extractor fit into the handle. This makes it highly compact and easy to carry.
Use
Effective use of an increment borer requires specialized training. Samples are taken at breast height or stump height of the tree depending on the user's objectives. During use the borer should be well lubricated; this makes the auger bit easier to use and helps to prevent the increment borer from becoming stuck in the tree.
Maintenance
Increment borers should be properly maintained to keep them in good working condition. They should be cleaned after use and dried before storing. Sharpening kits are also available and should be used when the auger bits become dull.
Types of borers
Increment borers come in different lengths and diameters and have different types of threads. The most common diameters are the 4, 4.15, and 5.3 millimeter borers. There are two different types of threading: two threading and three threading. Two threaded bores are more appropriate for hardwoods because they auger slower; this creates more torque when auguring into the tree. The three threaded auger will maneuver into the wood much faster than a two threaded auger.
