How Is It Used?The GRS Densitometer (TM) is used with the point-transect method of sampling. The point-transect samping requires the sampling technician to tally the existence of vegetation (and other cover conditions) at points along a transect. The GRS Densitometer allows the user to easily view the location of a transect point in the canopy to quickly determine if a tree crown is tallied or not.
The GRS Densitometer contains a mirror, sighting marks, and leveling bubbles allowing the user to project a vertical line-of-sight into the canopy. The field technician can simply look through the GRS Densitometer, level the two bubbles, align the sighting marks, and then talley (or skip) the point. Depending on the type of survey, you can record the various characteristics of the vegetation that intersect the point.
Unlike other common methods of estimating canopy cover, the GRS Densitometer-point-transect technique is efficient, accurate, and repeatable. In addition this technique can be integrated in to most field data measuring procedures and can, in many cases, replace existing methodologies.
The sample characteristics recorded at each point in the transect can include a wide variety of vegetation and non-vegetation conditions. Data on species, ground condition, soils, fire-fuels, and relative canopy position are just some of the features that can be collected and summarized for each transect or set of transects.
For estimating canopy cover, the point-transect method of sampling is more accurate and consistent 
than other cover estimation methods such as spherical mirrors or photo samples. The point transect method has been used for many years in rangeland and vegetation studies, but was difficult to implement in forested environment. Now, GRS presents a simple, lightweight tool for implementing this sampling procedure.
For additional information, please review the following paper:
''The Estimation of Forest Vegetation Cover Descriptions Using a Vertical Densitometer.''
To download GRS Densitometer documentation open
''GRS Densitometer Documentation''
