Height growth of sprouts emerged from small stumps and seed origin saplings under shade, in low elevation Fagus sylvatica L. s.l. stands in Greece

The objectives of this study were a) to analyze the growth of seed origin saplings and young stump sprouts, emerged from small dimension stumps that were established and grew under different shade and site conditions in low elevation Fagus sylvatica L. s.l. stands, which are located in northeastern Greece, and b) to examine whether those stump sprouts can be incorporated in the regeneration process of beech stands growing in analogous marginal, for the species conservation conditions. Fifty-six seed and sprout origin saplings were cut. The sprouts had emerged from stumps having a basal diameter lower than 7 cm. For each of the 56 saplings, the mean annual height increment was calculated, dividing the height of the sapling by the age of its base. The different shade regimes were determined using hemispherical photography. Sprouts, which grew in deep shade in both site types, and in the moderate shade in medium productivity sites, exhibited height growth analogous to seed origin plants growing under moderate and deep shade in good productivity sites, and under moderate shade in medium productivity sites. Moreover, even though it is of no practical significance, stump sprouts that were established and grew under moderate shade in good productivity sites, showed higher height growth rates than all the other (compared) categories of seed and sprout origin saplings. Consequently, sprouts can be used in various types and forms of shelterwood silvicultural systems where regeneration plants are established and grow under shade conditions. A few years after the emergence of sprouts, as regeneration cuttings proceed through the gradual removal of the mother trees, sprouts will probably exhibit high growth rates as a result of the improved light conditions and their pre-existing root system.