Dicyclic growth of shoots of Scotch pine (Pinus sylvestris L.) and the improvement silvicultural measures in the youngest pine cultures

In the publication, the partial results of the research project named Establishment and cultivation of pine stands of the first age degree in ecotopes disturbed by human activity are presented. That project was co-ordinated in 1995 - 1998 years by the Forest Research Station in Opocno. The thema of the project comes from an actual unsatisfactory development of young Scotch pine stands in some lowland part of the Czech Republic. During 1992 - 1993, a high percentage (over 70%) of unsatisfactory growth (bifureation) of shoots of Scotch pine (Pinus sylvestris L.) was observed in a young (2 - 7 years old) pine plantations on the eastern Bohemia (an eastern part of the Elbe River Region in the Czech Republic). One of the basic reasons is also the dicyclic (summer) growth of Lammas shoots and proleptic shoots during June after September. The growth and form deformations of the stem and crowns (habitus) of the Scotch pine are connected with the formation of proleptic shoots which flush from lateral buds, whereas the terminal bud is not developed. The summer (dicyclic) growth of shoots at the Scotch pine can be caused by various outside factors. These include mainly the increased offer of humidity and nutrients in the summer period after the finish of the spring (first) growing period. The growth disturbance caused by proleptic shoot growth is now the practical forestry problem especially in pine stands of 2 - 6 years after planting. The possible measure of tree form correction is seen in the formation of crowns by the cut of deformed shoots and in the removal of deformed pines from the plantations. The basic types of Lammas and proleptic shoots including types of practical improvement silvicultural measures are schematically and photographically illustrated.

Citation: Narovec, V. 2000: Dicyclic growth of shoots of Scotch pine (Pinus sylvestris L.) and the improvement silvicultural measures in the youngest pine cultures. [Dicyklicky rust výhonu u borovice lesni a napravna pestebni opatreni v nejmladsich kulturach.] 1. Ed. Kostelec nad Cernymi lesy, Lesnicka prace Ltd. 2000. 31 p.