Effects of planting time and ameliorating admixture on survival and growth of Norway spruce (Picea abies [L.] Karst.) plantation

Bareroot Norway spruce seedlings (2+2) were outplanted on planting site in Kremnicke vrchy Mts. (central Slovakia) in fall and spring planting times. In both planting times, in addition to untreated control, forest soil from nearby mature stand, peat, vegetative-bead ectomycorrhizal fungal inoculum or alginate-beads lack of fungus were added to planting holes. Four years after planting, survival rates were 90% and 93% for fall and spring planting time, respectively, from 88% to 96% for organic amendments and 91% for control. Fall-planted seedlings amended with peat had significantly higher stem diameter (21.3 mm) than spring-planted control (15.1 mm). A similar trend (though insignificant) in stem height, height increment and aboveground volume of seedlings was found. Very good growth of the fall-planted control seedlings was observed. The highest growth differences between planting times were also detected for control; the amendments mitigated these differences. The results suggest that planting of bareroot Norway spruce seedlings in the fall time has a potential to facilitate the satisfied survival and promoted growth of plantations as compared to spring time.