Effect of initial height of seedlings on the growth of planting material of Norway spruce (Picea abies [L.] Karst.) in mountain conditions

Abstract

Common ways of nursery cultivation and sorting the planting material of mountain provenances of Norway spruce (Picea abies [L.] Karst.) are connected with the risk of undesirable narrowing of the genetic spectrum of populations. Investigations in spruce plantations established by different planting materials found out very good growth (total height is 125 cm 9 years after outplanting) and health status of these slowly growing seedlings planted in extreme mountain conditions. In order to prevent the genetic spectrum narrowing, we recommend to cultivate all seedlings including smaller outsorted (commonly culled) ones. The smallest seedlings can be grown one year longer and subsequently planted out in the same locality as the remaining planting material of the same seed lot.