Bitter staff
A bitter stick is a simple instrument for carrying out the angle counting test , an efficient method for determining the stand area , which is an important parameter for assessing standing wood stocks in a forest. The instrument is named after its inventor, the forest scientist Walter Bitterlich .
properties
A bitter rod consists of a straight wooden or light metal rod and a metal plate or notch that is orthogonally attached to one of the two end faces of the rod. The ratio of the length of the rod to the width of the metal plate is 50: 1.
Other devices suitable for performing the angle counting test are the mirror relascope , which was also developed by Bitterlich, and the dendrometer by Horst Kramer . Compared to the mirror relascope, the bitter rod has a lower measurement accuracy. However, it has the advantage that it can also be made by private individuals with little effort.
application
- See main article Angle Counting .
For the angle counting test, one end of the rod is lifted close to the user's eye. Using the metal plate at the other end, each tree in the vicinity is sighted from a fixed point of view at chest height. The user turns around the starting point of the stick in front of his eye. Every tree that appears wider than the metal plate to the user is counted. Every tree counted after a full revolution corresponds to 1 m 2 of stand area per hectare (with a rod to metal plate ratio of 50: 1). Are z. B. counting 20 trees, this results in a stand area of 20 m 2 / ha. When recording trees, a distinction can be made between tree species.
Web links
further reading
- Horst Kramer , Alparslan Akça: Guide to forest measurement . 3rd, expanded edition. Sauerländer, Frankfurt am Main 1995, ISBN 3-7939-0830-5
Individual evidence
- ↑ The Kosmos Forest and Forest Lexicon. 2002. Stuttgart. P. 91. ISBN 3-440-09316-6