Manual Band Dendrometers (U.S. Patent #6009631 )

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Our Series 5 Manual Band Dendrometer is shown below. This is a visual or caliper readout, constant band tension instrument capable of reading changes in circumference. A schematic is shown below.

Manual Band Dendrometer - Picture

Operating Principle: The operating principle is based on the use of two concentric tubes. An outer tube is fixed relative to a point on the tree perimeter. One end of the band is fixed relative to this outer tube. The band is wrapped around the tree and attached to a movable inner tube concentric to and located within the fixed outer tube.

As the circumference of the tree changes length, the inner tube moves back and forth within the outer tube. Readout of circumference changes is obtained by visually determining changes in the position of the inner tube relative to the outer tube. For advanced users the corner of the square outer tube provides a unique path for determination of circumference changes with a high resolution digital caliper.

Procedure for determining changes in tree circumstance using a manual band dendrometer and a digital caliper is show on separate instruction page.

Extended Range Manual Band Dendrometer

Our extended range manual band dendrometer is capable of measuring a change in stem circumference of forty-five millimeters before a readjustment of the band setting is required.

This dendrometer has the same basic structure as the normal manual band dendrometer. The outer tube is 100mm in length instead of 60mm in length in the unit shown above.

Small Trunk Diameter Manual Band Dendrometer

Our small trunk diameter manual band dendrometer can be applied to trees with a diameter of two centimeters or larger.

This unit is the same design as shown in the figure. The major difference lies in the use of #2 threaded mounting rods with a diameter of approximately two millimeters

Manual Band Dendrometers
Element Manual Band Dendrometer (Series 5)
Size and Weight Approximate Size: 8 cm by 8 cm; Approximate Weight: 75 grams
Range Maximum unadjusted visual readout range is 22 millimeters. Adjusted range is set by the length of the band material at initial installation
Resolution Visual readout: 0.1 mm; digital caliper readout: 0.01mm*
Tension Principle Constant Force Spring, 0.61 or 1.22 newtons
Tension Level Low tension unit: 0.27 newtons (28 grams); High tension unit: 0.56 newtons (61 grams)
Band Characteristics Width: 3 millimeters: Thickness: 75 micrometers; Material: Hastalloy 276**; coefficient of thermal expansion 11.2 micrometers/meter/degree C
Band Material Supplied Low Tension unit: Two meters; High Tension unit: Three meters
Assembly Materials Stainless Steel, Brass, UV stabilized nylon
Mounting Method Two stainless steel threaded rods, 100 mm long; 3.35 mm outer diameter; Threading: 6-32**
Documentation Step by step installation brochure
* Footnote Recommended Caliper Readout Device: Starrett Electronic Digital #723
** Footnote Invar 36 can be supplied if specifically requested. However, it will corrode rapidly and will stain bark. The toxicity of this staining is presently unresolved.

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PHYTOGRAM™ - Applications and specifications Automatic Point and Band Dendrometers - For precise measurements of growth
POD - In the field data collection over extended periods of time Manual Band Dendrometers - Schematic drawing and product characteristics
Equipment Cost and Support Services - Products, Services, and typical packages Automatic Root Dendrometers - For measurement of diurnal cycles and growth rates of roots near the surface.
Environmental Sensors - For concurrent assays of air and ground temperature, light, and soil moisture Sensor Cluster Layout - Field layouts of sensors for production and research applications
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Proton-Days™ - Quantify plant response to weather at different sites (similar to Degree-Days) Dendrometer User Group Pages
Sucrose Transport - Method of determining magnitude and uniformity of sucrose transport between leaf and fruit Water Content of Specific Crops
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