An auxanometer (Gr. '= "to grow" + ''metron''= "measure") is an apparatus for measuring increase of growth in
plant
Plants are predominantly photosynthetic eukaryotes of the kingdom Plantae. Historically, the plant kingdom encompassed all living things that were not animals, and included algae and fungi; however, all current definitions of Plantae excl ...
s.
In case of an arc-auxanometer (see picture), there is a thin cord fixed to the plant apex on one end and a dead-weight on the other with a pointer indicating against an arc scale. In some forms it passes over a
pulley which has a pointer attached to it. When the plant's height increases, the pulley rotates and the pointer moves on a circular scale to directly give the
magnitude of growth. The "rate of growth" is a derived measurement obtained by dividing the length of growth measured by the auxanometer, by the time said measurement took. It is also called an arc-indicator. These simple types of auxanometer have been replaced by rotation sensors at the fulcrum point linked to dataloggers with a balancing beam attached to the growing tip/plant apex.
Sensitive auxanometers allow measurement of growth as small as a
micrometer Micrometer can mean:
* Micrometer (device), used for accurate measurements by means of a calibrated screw
* American spelling of micrometre
The micrometre ( international spelling as used by the International Bureau of Weights and Measures; ...
, which allows measurement of growth in response to short-term changes in
atmospheric composition.
Auxanometers are used in laboratory,
the field, and the classroom.
See also
*
Crescograph
References
{{Reflist
Measuring instruments