Features of the growth of balsamic poplar Populus balsamifera L. In an urban environment

Abstract

A study of the state of poplar plantations of balsamic Populus balsamifera L., which are in the stage of decay and assigned to logging in 2022, showed differences that arose during the full life cycle in fundamentally different growing conditions. Thus, in conditions of high anthropogenic load on the Novosibirsk Street and road network, the average diameter of the trunk at the base was 11.8 cm larger than that of the balsamic poplar, which grew in conditions of minimal anthropogenic load of urban forests of Novosibirsk. The maximum growth of balsamic poplar in urban forests is characterized by the first three decades of tree growth, then a gradual decrease in growth begins. The difference in growth over the first and last decades of tree life is 2.4 times. While for poplars growing on the Railway Line, the first two decades of tree growth are characterized by the maximum increase, then a gradual decrease in growth begins. The difference in growth over the first and last decades of tree life is only 27%. That is, the decrease in the volume of wood growth over time, especially in the last three decades of active development of urban road transport is not confirmed. While the decrease in the volume of growth in the conditions of competition in urban forests is becoming more noticeable every decade. Another important factor in assessing the condition of wood is its fautiness. In this case, all the negative environmental impact on the Railway line determined the formation and development of many defects of wood. Of the twenty-six specimens of balsamic poplar, 19 had wood cracks at the base of the trunk (73%). Three specimens (11%) had extensive hollows at the base of the trunk, probably obtained as a result of mechanized harvesting in winter. Five specimens (19%) had obvious signs of the presence of table rot with the destruction of wood. Plantings that grew in urban forests had fewer wood defects. These include the presence of cracks in seven copies of balsamic poplar (43%) and two copies at the time of demolition were dead wood of previous years. There were no signs of the presence of stem rot and hollows, frost-breaking cracks at the base of the trunks.