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Large area of spruce forest had declined in the summit parts of Czech mountains before air pollution load was reduced in the 1990s. To restore forest, clear-cuts were planted with exotic coniferous species (blue spruce prevailed). Later, decreased air pollution load allowed planting Norway spruce and autochtonous broadleaves. However, the broadleaved plantations often failed (microclimate, game, mice), mainly those consisting of target species, such as European beech and sycamore maple. Therefore, diversification of pure coniferous stands in terms of tree species composition is still highly desirable. Silver birch, Carpathian birch, Silesian willow, European aspen and rowan plantations are native pioneer species potentially applicable to diversification or conversion of coniferous stands under conditions of harsh environment of the Jizerské hory Mts., Northern Bohemia. In addition to broadleaves, Norway spruce was also planted within the experiment. The species mean heights were compared using the mean heights reached in the 14th year after planting. Carpathian birch performs the best having significantly greater mean height (244 – 253 cm) and high survival (78 – 94 %). Silver birch has similar height (235 – 273 cm) though its survival is much lower (ca 25 %). Both birches have comparable height with Norway spruce (221 – 287 cm). As for mean height, these three species differ significantly (p = 0.05) from the other broadleaves (rowan, aspen and willow). Silesian willow is of lesser importance to create productive stands, however the species is able to survive (78 – 90 %) well at the high altitude (975 m a.s.l.).