Juniper dwarf mistletoe is one of the major parasites on junipers and other species in the Cupressaceae family. To date, there has been no research conducted on its distribution in Slovenia. Project goals were: to determine its distribution in Slovenia; to determine which species are its hosts; assess the degree of infection and the potential damage to the hosts; and assess the need for potential control. In 2011, 11 plots were inventoried, of which 6 were infected with juniper dwarf mistletoe. All hosts on a given plot were determined their GPS coordinates, altitude, species (Prickly Juniper or Common Juniper), vigor, and the level of infection due to juniper dwarf mistletoe. As a basis in assessing the rate of infection the Hawksworth six-class dwarf mistletoe rating system (DMR) was used. For purposes of our research, we adapted this system and extended it to 12 classes. The dimensions of juniper dwarf mistletoe were surprisingly large, we often encountered speciments greater than 25 cm, the largest measuring even up to slightly less than 40 cm. The proportion of infected hosts per plot ranged between 29,17 % and 82,93 %. The proportion of infected Prickly Juniper specimens was 76,56 %, while this percentage was 54,90 % for Common Juniper. We often observed a different pattern of infection on Common Juniper than on Prickly Juniper. Infections on Common Juniper were more localized, in many cases there was only one single infection present, mostly on the trunk in the middle third of the crown, less often on the branches. Out of a total 56 infected Common Junipers, 12 were such, of which 7 with an infection in the middle third of the trunk. So far, its control in our country is probably not yet necessary.
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