The cowberry population (Vaccinium vitis-idaea) of the northwestern region of Belarus was studied from the resource-based point of view. Reliable regression equations of the connection between the projective cover and the resource phytomass have been created.

On the obtained material the authors tested equations of similar dependencies obtained by other authors. Equations from nearby regions (North-East of Belarus) showed a high degree of accuracy in estimating the abundance of phytomass by abundance in northwestern populations, and the dependencies obtained from continental regions or from global generalizations are overestimated.

Linear and non-linear functions can be applied equally for rapid assessment of resource-significant cowberry populations (projective coverage of more than 10%) taking into account the variability of abundance (and height of shoots) of cowberries.

The projective weight (leaves, air-dry raw materials) for cowberry varies in the conditions of the North-West of Belarus in the range from 1 to 2 g / m2 /% and is a more stable resource indicator than the yield and abundance, which gives grounds for its practical application in the Botanical Resource Science and Phytocenology.