Przyrost i wzrost nadziemnej i podziemnej części podrostów jodłowych w Nadleśnictwie Piotrków Trybunalski

The objective of the research was to determine the relationship between the dimensions and increment of the aboveground (easy to determine) and the belowground biomass of fir undergrowth in different shelter conditions. In the examined samples, the length of taproots (DKp) up to the age of 30 was dependent on its increment during the first three years of development. Later years saw an intensified growth of taproots. However, the differences from the first years of growth did not compensate for the differences in the first years. Reduced DKp growth was observed in the group of seedlings incrementing to a height of less than 4 cm. The height increment of fir undergrowth at about 20 years of age should not be less than 20 cm. The growth of roots and aboveground parts depends on other factors. The growth of roots was related to the growth of aboveground parts only to a small degree. Under the conditions of suppression, the extremely poor height increment of firs was compensated by the development of the aboveground biomass. With a moderate height increment (sufficient light availability) root growth was more intense. No clear relationship was found between the development of taproots and horizontal roots.