An explanation and demonstration of using a wedge prism to estimate basal area. Filmed by Patrick Culbert, University of British Columbia - Faculty of Forestry
man, whoever this Forester is, he needs to be teaching in a lot more videos. So many foresters give WAAAY too much information. His way of almost speaking in laymen's terms works well. keep up the good work Patrick
When I heard that you can measure the basal area with a prism, the first thing in my mind was ' That doesn't sound very precise or true' but... it actually works. Worth to always keep an open mind I guess
When you purchase a prism, you select the desired BAF (there are also metric prism in m^2/ha and standard in ft^2/acre). They are usually labelled on the edge.
@@alinawaz7256 A number of devices that work on a similar principle as prisms (e.g., an angle gauge or Cruz-All) need to be held a specific distance from your eye, but a prism does not (though it must be held over the center point of the plot). From Forestry Supplier's: "Hold prism at any convenient distance from the eye, directly over the sampling point. Hold in a vertical position and at a right angle to the line of sight." (www.forestry-suppliers.com/Documents/1435_msds.pdf)
