FEATURES OF GROWTH AND STATE OF FOREST-STEPPE AND STEPPE ECOTYPES OF SCOTS PINE IN PROVENANCE TRIAL PLANTATIONS OF THE VORONEZH REGION

Abstract

The indicators characterizing growth, productivity and living conditions of forest-steppe and steppe ecotypes of Scots pine in provenance trial plantation of Stupinsky Pole training ground in the Voronezh Region, obtained in 2019 on temporary sample plots, have been analyzed. The object of comprehensive research are forest-steppe and steppe ecotypes of Scots pine in 60-year-old provenance trial plantations growing in the Ramonsky district forestry of the Voronezh forestry. The studied cultures were laid on the lands after agricultural use in 1959 under the guidance of Professor M. M. Veresin. The planting material was 2-year-old standard seedlings of Scots pine, planted manually under Kolesov's planting iron. The type of growing conditions is A2 and B2. No additional planting was made. Based on the materials of 13 test plots laid according to the standard method, some features of the growth of forest-steppe and steppe pine ecotypes has been revealed. Their productivity and living condition have been evaluated. The highest average height is a characteristic of the steppe ecotype from the seeds of the Valsky forestry of the Saratov region and the forest-steppe ecotype from the seeds of the Platonov forestry of the Tambov region. The lowest average height is in crops of the forest-steppe ecotype from the seeds of the Monastic forestry of the Penza region. Local ecotypes (seeds from the Khrenovsky forestry) have the largest average diameter. The steppe ecotypes from the Saratov Region have the smallest diameter. The variability of the diameters of the preserved 60-year-old trees at a height of 1.3 m and at the surface of the soil was estimated as average - 16.99-31.09% and 19.50-29.94%, respectively. It is also typical for ordinary forest plantations. All the trees are classified as industrial trees. The stock of raw wood depends on the stand density. The largest stock was recorded in cultures from the Bryansk region (Krasnoslobodskoye forestry) due to the greater number of preserved trees. The smallest is among forest-steppe ecotypes of the Belgorod region. The analysis of the vital state of the surviving plants has showed that the best indicators have forest-steppe ecotypes from adjacent areas with similar climatic conditions. At the same time, the amount of preserved pine trees of all ecotypes per 1 ha is not large. Their preservation is 3.8-10.2% of the trees planted in 1959. Preservation varies greatly in ecotypes. Edaphic conditions for the growth of maternal stands where seeds were harvested have a significant impact on the living conditions of pine provenance trial plantations