Contribution to the Judgement of Seasonal Dynamics of Height Growth of Scotch Pine, Black Pine and Weymouth Pine

1992

S. 115-122

6 Lit. Ang.

Unselbständiges Werk

200038082

Three species from genus Pinus: Scotch pine, black pine and Weymouth pine are used, more or less, in Croatian forestry for the establishment of forest cultures. Height growth dynamics of these three species has been observed during 1983, 1984 and 1985 vegetation in the nursery of Forestry Research Institute, Jastrebarsko. Measurements were carried out on 9 plants of each species and were conducted every ten days. The age of plants in the beginning of observation was five years. Weather station for conducting observations of climatic phenomena is in the nursery. According to obtained weather data, it is evident that the three-year period (1983-1985) of observing height growth was, on the whole, somewhat warmer and drier in May and July, and more humid in June than the average of several years. The carried out researches revealed the following: - Scotch pine achieves the major part of annual height increment in May 69.3%, then in June 15.6%, and in April 14.9%. Height growth actually terminates by the and of June. The duration of summer vegetation is from 72 days in 1984 to 84 days in 1985. - Black pine achieves the major part of annual heigt increment also in May, 63.2%, then in April, 27.8%, and in June, only 6.5%. The duration of summer vegetation is from 61 day in 1983 to 84 days in 1984. - Weymouth pine achieves the major part of annual heigt increment in May, 65.4% then in June 19.6% and in April 14.8%. By the end of June height increment is actually over. The duration of summer vegetation is from 61 day in 1983 to 84 days in 1985.