We compared two smartphone applications for estimating stand basal area and number of stems per hectare, the application MOTI and the application TRESTIMA®. TRESTIMA® analyzes photographs, taken in the forest, using computer vision and dendrometric functions to estimate basal area, diameter distribution and growing stock. We measured basal area and number of stems on 61 plots in 4 stands, with mostly large diameter Norway spruce in forest management unit Velike Lašče. TRESTIMA® slightly overestimates basal area and number of stems per ha. In the chosen profile which was most suitable for our stands, TRESTIMA® recognized spruce and Scots pine, but did not distinguish between spruce and silver fir. MOTI proved to be more useful than TRESTIMA® for measuring stand basal area and number of stems. TRESTIMA® was problematic particularly for not recognizing all major tree species and due to too small learning set for calculating the height curves.
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