Vool, E.; Karp, K.; Starast, M., Paal, T. and Luik, A. 2011. Growth Habit of Arctic Bramble (Rubus arcticus) within Kaansoo Conservation Area in Estonia. Baltic Forestry 17(2): 170-178

Arctic bramble (Rubus arcticus L. ssp. arcticus) is a relic of sub-arctic climatic conditions in Estonia. It has been a protected species since 1958 but there has been a steady reduction in its natural area of distribution, which is possibly due to habitat degradation and conversion to agricultural land. Therefore, the influence of habitat conditions in arctic bramble vegetative growth parameters needed clarification. The focus of this research is on five types of arctic bramble natural habitat and one plantation, in which plants originated from one of the natural habitats. The analysis of the results showed that the plants did not reproduce in nature and that there were considerable differences in the plants’ petiole length, shoot length, and node number per shoot compared to those growing in the plantation. Light unweighted forest trees canopy openness and habitat light levels had a significant impact on arctic bramble vegetative growth parameters in Kaansoo natural habitats. Light canopy openness and diffuse solar radiation encouraged shoot elongation and plant vegetative growth. Bryophyte and dicotyledonous companion plants influenced arctic bramble growth;an increase in the number of companion plants increased the node number and leaf number per shoot. Soil pH was negatively correlated with leaf size and dry weight and between soil moisture and petiole length. Soil moisture was positively correlated with node number per shoot, leaf number per shoot and N-Tester values (which measure light transmittance).

Keywords:shoot length and number, node number, leaf parameters, plant dry weight, soil moisture and pH, companion plants, illumination.