Succession of the crimean pine by the english oak and its natural regeneration in the North-Western Caucasus
The purpose of the research is to identify the reason for the succession of the Crimean pine by the English oak and its natural regeneration in the North-West Caucasus. To achieve the goal a preliminary selection of plantations has been carried out for taxation measurements. The final selection of objects for laying out sample plots and studying natural regeneration has been carried out during the field reconnaissance survey of previously selected units. Temporary sample plots were laid in the English oak standings of different ages in accordance with the standard method. The reasons have been studied for the succession of the Crimean pine species by the English oak in accordance with their environmental requirements. The forest taxation characteristic has been given and the account of natural regeneration on the investigated sites has been carried out. The studies were carried out in fresh oak forests mixed with the Crimean pine and the European hornbeam crops in the Khadyzhensk and Shirvan district forests of the North-West Caucasus. Soil samples were taken and their pH was determined. It’s been noted that in the researched area all the crops grow in favorable environmental conditions, excluding the Crimean pine, which does not tolerate acidic soils, but prefers neutral and alkaline ones. Studies have shown that in low-stem planting of the English oak there is a gradual loss of the Crimean pine from the species composition. This occurs due to the sour soil. The presence of self-seeding and small undergrowth of the English oak indicates its fruiting. Regeneration of plantations out of the English oak mainly occurs with the participation of common ash, European hornbeam, wild fruit trees in fresh oak wood. The English oak in the North-West Caucasus is of great forest management importance. Therefore, periodic low intensity opening of the oak stand in the form of thinning is recommended as one of the effective measures to improve the safety of oak undergrowth.